JP2008024874A - Curable composition, antireflection film, and polarizing plate and image display device, using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable composition; a film and an antireflection film having excellent scratch resistance, using the composition; and a polarizing plate and an image display device, using the antireflection film. <P>SOLUTION: The curable composition contains (A) at least one fluorine-containing polymer having at least each one of a fluorine-containing vinyl monomer polymerization unit (a) and a hydroxy group-containing vinyl monomer polymerization unit (b) wherein the share ratio of the polymerization unit (b) is more than 20 mol%, (B) at least one crosslinking agent capable of reacting with a hydroxy group and (C) at least one compound which generates an acid by irradiation with an ionizing radiation. The followings are also provided: a cured product obtained by using the composition; the film or the antireflection film, having a layer formed by coating the composition onto a transparent support; the polarizing plate using the antireflection film; and the image display device using the antireflection film or the polarizing plate on the outermost surface of the display. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention uses a curable composition, a film having a layer comprising the composition, an antireflection film, a polarizing plate using the antireflection film, and the antireflection film or the polarizing plate on the outermost surface of a display. The present invention relates to an image display device.

  In general, an antireflection film is used for an image display device such as a cathode ray tube display (CRT), a plasma display (PDP), an electroluminescence display (ELD), a liquid crystal display (LCD), etc. In order to prevent reflection of images and images, it is arranged on the outermost surface of the display so as to reduce the reflectance by using the principle of optical interference.

  Such an antireflection film can be generally produced by forming a low refractive index layer having an appropriate film thickness having a lower refractive index than that of the support on the support. In order to realize a low reflectance, it is desirable to use a material having a refractive index as low as possible for the low refractive index layer. Moreover, since an antireflection film is used for the outermost surface of a display, high scratch resistance is required. In order to realize high scratch resistance in a thin film having a thickness of around 100 nm, the strength of the coating itself and the adhesion to the lower layer are required.

In order to lower the refractive index of the material, there are means such as (1) introducing fluorine atoms, (2) lowering the density (introducing voids), etc., both of which decrease the film strength and interface adhesion, The scratch resistance is in the direction of decreasing, and it has been a difficult task to achieve both low refractive index and high scratch resistance. In order to achieve high scratch resistance, it is important to sufficiently advance the curing reaction. From the viewpoint of productivity, it is advantageous to cure the film by some method after applying the fluorine-containing polymer to the support. Patent Documents 1 and 2 propose a method of curing a low refractive index layer of an antireflection film by reacting a hydroxyl group of a fluoropolymer with a curing agent using an acid catalyst. Patent Document 3 proposes a curable resin composition containing a fluorine-containing polymer having a hydroxyl group, a curing agent, and a photoacid generator having a specific structure.
Japanese Patent Laid-Open No. 10-25388 JP 2003-222702 A JP 2001-89623 A

  In the techniques of Patent Documents 1 and 2, when sulfonic acid is used as the curing catalyst, there is a problem that the coating surface condition is deteriorated because the stability of the coating liquid is poor. Further, when a thermal acid generator is used as a curing catalyst, the heating temperature is high and the curing time is long, so there is a problem that the load on the production equipment is large and the productivity is poor, and improvement has been desired.

  Further, in the techniques of Patent Documents 1 and 3, since the hydroxyl group content in the fluoropolymer having a hydroxyl group is low, there is a problem that the strength of the formed cured film is insufficient and the scratch resistance is deteriorated, and improvement is desired. It was rare.

An object of the present invention is to provide a composition in which a coating solution has high stability, can be cured under milder conditions, and can form a cured product having high strength. Another object of the present invention is to provide a film and an antireflection film having excellent scratch resistance using the composition. Furthermore, it is providing the polarizing plate and image display apparatus using such an antireflection film.

  As a result of intensive studies, the present inventors use a composition containing a fluorine-containing polymer having a polymer unit content of a hydroxyl group-containing vinyl monomer exceeding 20 mol%, a crosslinking agent, and a compound that generates an acid upon irradiation with ionizing radiation. Thus, the present inventors have found a cured composition that can be cured under mild conditions and has good scratch resistance of the formed cured film. It was also found that a film having high manufacturing suitability and excellent scratch resistance can be formed using the film.

  According to the present invention, a curable composition, a cured product, a film, an antireflection film, a polarizing plate, and an image display device having the following constitution are provided, and the above object is achieved.

[1] The following components (A), (B) and (C):
(A) a fluorine-containing polymer containing at least one fluorine-containing vinyl monomer polymerization unit (a) and a hydroxyl group-containing vinyl monomer polymerization unit (b), and the proportion of the polymerization unit (b) exceeding 20 mol% At least one,
(B) at least one crosslinking agent capable of reacting with a hydroxyl group, and (C) at least one compound that generates an acid upon irradiation with ionizing radiation,
A curable composition comprising:

[2] The fluoropolymer (A) further contains at least one polymer unit (c) having a graft site containing a polysiloxane repeating unit represented by the following general formula (1) in the side chain, and the main chain is Curable composition as described in said [1] which consists only of carbon atoms.
General formula (1):

In formula (1), R ¹¹ and R ¹² may be the same or different and each represents an alkyl group or an aryl group. p represents an integer of 5 to 500.

[3] The curable composition according to the above [1], wherein the fluoropolymer (A) further contains a polysiloxane repeating unit (d) represented by the following general formula (1) in the main chain.
General formula (1):

In formula (1), R ¹¹ and R ¹² may be the same or different and each represents an alkyl group or an aryl group. p represents an integer of 5 to 500.

[4] The composition further contains a compound having a polysiloxane structure containing a hydroxyl group, a functional group capable of reacting with the hydroxyl group to form a bond, or a functional group capable of reacting with the crosslinking agent to form a bond. The curable composition in any one of said [1]-[3].
[5] Any of the above [1] to [4], wherein the crosslinking agent is a compound containing a nitrogen atom in the molecule and containing two or more carbon atoms substituted with an alkoxy group adjacent to the nitrogen atom. A curable composition according to any one of the above.

[6] A cured product obtained by curing the curable composition according to any one of [1] to [5].

[7] A film having a layer formed by applying the curable composition according to any one of [1] to [5] on a transparent support.
[8] An antireflection film having a low refractive index layer formed by coating the curable composition according to any one of [1] to [5] on a transparent support.

[9] A polarizing plate, wherein the antireflection film according to [8] is used for one of the two protective films of the polarizing film in the polarizing plate.

[10] An image display device characterized in that the antireflection film as described in [8] above or the polarizing plate as described in [9] above is used on the outermost surface of the display.

  The curable composition of the present invention can be cured under mild conditions and gives a cured product having high strength. Moreover, the film which has a layer obtained using this composition can be manufactured on mild conditions, and is excellent in scratch resistance. In particular, it is highly suitable for producing an antireflection film in which a low refractive index layer is formed using the composition, and is excellent in scratch resistance while having sufficient antireflection properties. Furthermore, the image display device provided with the antireflection film of the present invention and the image display device provided with a polarizing plate using the antireflection film of the present invention have little reflection of external light and background reflection, and are extremely visible. High nature.

  Hereinafter, the present invention will be described in detail. 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”. . The term “on the support” as used in the present invention includes both the case where the surface directly refers to the support and the case where the surface includes a layer (film) provided on the support. is there.

<Curable composition>
The curable composition of the present invention contains (A) at least one fluorine-containing vinyl monomer polymerization unit (a) and a hydroxyl group-containing vinyl monomer polymerization unit (b), and the proportion of the polymerization unit (b) is Containing at least one fluorine-containing polymer in excess of 20 mol%, (B) at least one crosslinking agent capable of reacting with a hydroxyl group, and (C) at least one compound that generates an acid upon irradiation with ionizing radiation. Features.
Hereinafter, the fluorine-containing polymer will be described in detail.

[Fluoropolymer (A)]
[Fluorine-containing vinyl monomer polymerization unit (a)]
In the present invention, the structure of the fluorine-containing vinyl monomer polymerization unit (a) contained in the fluorine-containing polymer (A) used for forming the low refractive index layer is not particularly limited, and examples thereof include fluorine-containing olefin, perfluoroalkyl vinyl ether, Polymerized units based on vinyl ethers having a fluorine alkyl group or (meth) acrylates can be mentioned. The fluorine-containing polymer is preferably a copolymer of a fluorine-containing olefin and a vinyl ether because of suitability for production and properties required for a low refractive index layer such as a refractive index and film strength. More preferably, it is a copolymer. Further, as a copolymer component, perfluoroalkyl vinyl ether, vinyl ether having a fluorine-containing alkyl group, (meth) acrylate, or the like may be included for the purpose of reducing the refractive index.

  As the perfluoroolefin, those having 3 to 7 carbon atoms are preferable, perfluoropropylene or perfluorobutylene is preferable from the viewpoint of polymerization reactivity, and perfluoropropylene is particularly preferable from the viewpoint of availability.

The content of perfluoroolefin in the polymer is preferably 25 to 75 mol%. In order to lower the refractive index of the material, it is desired to increase the introduction rate of perfluoroolefin, but in the point of polymerization reactivity, introduction of about 50 to 70 mol% is the limit in a general solution-based radical polymerization reaction. There is more than that. In the present invention, the content of perfluoroolefin is preferably 30 to 70 mol%, more preferably 30 to 60 mol%, still more preferably 35 to 60 mol%, and further preferably 40 to 60 mol%. % Is particularly preferred.

  In order to reduce the refractive index, the fluoropolymer (A) used in the present invention may be copolymerized with a perfluorovinyl ether represented by the following general formula M2. The copolymer component may be introduced into the polymer in the range of 0 to 40 mol%, preferably 0 to 30 mol%, more preferably 0 to 20 mol%.

In the Formula M2, Rf ¹² represents a fluorine-containing alkyl group having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, particularly preferably containing fluorinated alkyl group having 1 to 10 carbon atoms, 1 to carbon atoms More preferably, it is 10 perfluoroalkyl groups. The fluorinated alkyl group may have a substituent. Specific examples of Rf ¹² include -CF ₃ {M2- (1)}, -CF ₂ CF ₃ {M2- (2)}, -CF ₂ CF ₂ CF ₃ {M2- (3)}, -CF ₂ CF (OCF ₂ CF ₂ CF ₃ ) CF ₃ {M2- (4)} and the like.

  In the present invention, a fluorine-containing vinyl ether represented by the following general formula M1 may be copolymerized to reduce the refractive index. The copolymer component may be introduced into the polymer in the range of 0 to 40 mol%, preferably 0 to 30 mol%, particularly preferably 0 to 20 mol%.

In the general formula M1, Rf ¹¹ represents a fluorine-containing alkyl group having 1 to 30 carbon atoms, preferably a fluorine-containing alkyl group having 1 to 20 carbon atoms, particularly preferably 1 to 15 carbon atoms, _{CF 2 CF 3, -CH 2 (} CF 2) q1 H, -CH 2 CH 2 (CF 2) q1 F: even (q1 2 to 12 integer) such}, branched structure {e.g. CH (CF ₃ ) ₂ , CH ₂ CF (CF ₃ ) ₂ , —CH (CH ₃ ) CF ₂ CF ₃ , —CH (CH ₃ ) (CF ₂ ) ₅ CF ₂ H, etc.} It may have a formula structure (preferably a 5- or 6-membered ring such as a perfluorocyclohexyl group, a perfluorocyclopentyl group or an alkyl group substituted with these), and an ether bond (for example, —CH ₂ OCH ₂ CF ₂ CF ₃ , —CH ₂ CH ₂ OCH ₂ (CF ₂ ) _{q 2 H, -CH 2 CH 2 OCH} 2 (CF 2) q2 F (q2: 2~12 integer), CH like _{2 CH 2 OCF 2 CF 2 OCF} 2 CF 2 H) may have. The substituent represented by Rf ¹¹ is not limited to the substituent described here.

  Examples of the monomer represented by the general formula M1 include “Macromolecules”, Vol. 32 (21), p. 7122 (1999), a method in which a fluorine-containing alcohol is allowed to act on a leaving group-substituted alkyl vinyl ether such as vinyloxyalkyl sulfonate and vinyloxyalkyl chloride as described in JP-A-2-721. A method of exchanging vinyl groups by mixing a fluorine-containing alcohol and a vinyl ether such as butyl vinyl ether in the presence of a palladium catalyst as described in International Patent Application No. 92/05135; as described in US Pat. No. 3,420,793. , A method in which a fluorine-containing ketone and dibromoethane are reacted in the presence of a potassium fluoride catalyst, followed by a de-HBr reaction with an alkali catalyst;

[Hydroxyl group-containing vinyl monomer polymerization unit (b)]
The fluorine-containing polymer (A) used in the present invention contains a hydroxyl group-containing vinyl monomer polymerization unit (b), but the content thereof is an amount exceeding 20 mol%. A hydroxyl group has a function of curing by reacting with a crosslinking agent, and a higher hydroxyl group content is preferable because a hard film can be formed. The content is more preferably more than 20 mol% and not more than 70 mol%. It is more preferably 25 mol% or more and 60 mol% or less, and further preferably 25 mol% or more and 55 mol% or less.

  As the hydroxyl group-containing vinyl monomer, any vinyl ethers, (meth) acrylates, styrenes and the like can be used as long as they are copolymerizable with the above-described fluorine-containing vinyl monomer polymerization unit. For example, when a perfluoroolefin (such as hexafluoropropylene) is used as the fluorine-containing vinyl monomer, it is preferable to use a hydroxyl group-containing vinyl ether having good copolymerization properties, specifically 2-hydroxyethyl vinyl ether, 4-hydroxybutyl. Examples thereof include, but are not limited to, vinyl ether, 6-hydroxyhexyl vinyl ether, 8-hydroxyoctyl vinyl ether, diethylene glycol vinyl ether, triethylene glycol vinyl ether, 4- (hydroxymethyl) cyclohexyl methyl vinyl ether, and the like.

[Structural unit (c) or (d) having a polysiloxane structure]
The fluoropolymer (A) used in the present invention preferably has a structural unit having a polysiloxane structure in order to impart antifouling properties. The fluorine-containing polymer having a polysiloxane structure useful in the present invention includes (a) a fluorine-containing vinyl monomer polymerization unit, (b) a hydroxyl group-containing vinyl monomer polymerization unit, and (c) a side chain represented by the following general formula (1). Or a fluorine-containing polymer comprising at least one polymer unit having a graft site containing a polysiloxane repeating unit and having a main chain composed only of carbon atoms, or (a) a fluorine-containing vinyl monomer polymer unit, and (b) a hydroxyl group. Examples thereof include a fluorine-containing polymer containing at least one kind of vinyl monomer polymerization unit, and (d) a polysiloxane repeating unit represented by the following general formula (1) in the main chain.
General formula (1):

In formula (1), R ¹¹ and R ¹² may be the same or different and each represents an alkyl group or an aryl group. As an alkyl group, C1-C4 is preferable and a methyl group, a trifluoromethyl group, an ethyl group etc. are mentioned as an example. The aryl group preferably has 6 to 20 carbon atoms, and examples thereof include a phenyl group and a naphthyl group. Among these, a methyl group and a phenyl group are preferable, and a methyl group is particularly preferable. p represents an integer of 5 to 500, preferably 8 to 350, and particularly preferably 10 to 250.

{Polymerized unit (c) having a graft site containing a polysiloxane repeating unit in the side chain}
Examples of the polymer having a polysiloxane structure represented by the general formula (1) in the side chain are “J. Appl. Polym. Sci.”, 2000, p. 78 (1955), as disclosed in JP-A-56-28219 and the like, a reactive group (with respect to a polymer having a reactive group such as an epoxy group, a hydroxyl group, a carboxyl group, an acid anhydride group) For example, polysiloxane having an epoxy group, an acid anhydride group, an amino group, a mercapto group, a carboxyl group, a hydroxyl group, etc.) at one end (for example, “Silaplane” series (manufactured by Chisso Corporation)) is polymerized. Can be synthesized by a method of introducing a polysiloxane-containing silicon macromer, and both methods can be preferably used. In the present invention, a method of introducing by polymerization of silicon macromer is more preferable.

The silicon macromer may be any one having a polymerizable group capable of copolymerization with a fluorine-containing olefin, and is preferably represented by any one of the general formulas (1-1) to (1-4). It is a structure.

In the general formulas (1-1) to (1-4), R ¹¹ , R ¹² and p represent the same meaning as in the general formula (1), and preferred ranges thereof are also the same. R ^{13 to} R ¹⁵ each independently represents a substituted or unsubstituted monovalent organic group or a hydrogen atom, an alkyl group having 1 to 10 carbon atoms (for example, a methyl group, an ethyl group, an octyl group, etc.), a carbon number of 1 10 to 10 alkoxy groups (for example, methoxy group, ethoxy group, propyloxy group and the like), aryl groups having 6 to 20 carbon atoms (for example, phenyl group, naphthyl group and the like) are preferable, and alkyl groups having 1 to 5 carbon atoms are particularly preferable. . R ¹⁶ represents a hydrogen atom or a methyl group. L ₁₁ represents an arbitrary linking group having 1 to 20 carbon atoms, and examples thereof include a substituted or unsubstituted linear, branched or alicyclic alkylene group, or a substituted or unsubstituted arylene group, preferably carbon. It is an unsubstituted linear alkylene group of 1 to 20, particularly preferably an ethylene group or a propylene group. These compounds are synthesized, for example, by the method described in JP-A-6-322053.

  Any of the compounds represented by the general formulas (1-1) to (1-4) can be preferably used in the present invention, but among these, the general formula ( The structure represented by 1-1), (1-2) or (1-3) is preferable. The polysiloxane moiety preferably occupies 0.01 to 20% by mass of the graft copolymer, more preferably 0.05 to 15% by mass, and particularly preferably 0.5 to 10% by mass. %.

  Although the preferable example of the polymer unit of the polymer graft part which contains a polysiloxane part in the side chain useful for this invention below is shown, this invention is not limited to these.

S- (36): “Silaplane FM-0711” {manufactured by Chisso Corporation},
S- (37): “Silaplane FM-0721” (same as above),
S- (38): “Silaplane FM-0725” (same as above).

{Polysiloxane repeat unit (d) contained in main chain}
There is no particular limitation on the method for introducing a polysiloxane structure into the main chain. For example, a method using a polymer-type initiator such as an azo group-containing polysiloxane amide described in JP-A-6-93100, a polymerization initiator, a chain transfer agent A method in which a reactive group derived from a polymer (for example, a mercapto group, a carboxyl group, or a hydroxyl group) is introduced into a polymer terminal and then reacted with a polysiloxane containing one or both terminal reactive groups (for example, an epoxy group or an isocyanate group), hexa Examples thereof include a method of copolymerizing a cyclic siloxane oligomer such as methylcyclotrisiloxane by anionic ring-opening polymerization, among which a method using an initiator having a polysiloxane structure is easy and preferable.

As the polysiloxane structure introduced into the main chain of the fluoropolymer (A) used in the present invention, a structure represented by the general formula (2) is particularly preferable.
General formula (2):

In the general formula (2), R ¹¹ , R ¹² , R ²¹ and R ²² are each independently an alkyl group (preferably having 1 to 5 carbon atoms, such as a methyl group or an ethyl group) or an aryl group. (C6-C10 is preferable, and examples thereof include a phenyl group and a naphthyl group), which may further have a substituent, preferably a methyl group or a phenyl group, and particularly preferably methyl. It is a group.

R ^{23 to} R ²⁶ are each independently a hydrogen atom, an alkyl group (preferably having 1 to 5 carbon atoms, such as a methyl group or an ethyl group), or an aryl group (preferably having 6 to 10 carbon atoms). Represents a phenyl group or a naphthyl group), an alkoxycarbonyl group (preferably having 2 to 5 carbon atoms, such as a methoxycarbonyl group or an ethoxycarbonyl group) or a cyano group, preferably an alkyl group or alkoxycarbonyl Group and a cyano group, and particularly preferably a methyl group and a cyano group.

  r1 and r2 each independently represents an integer of 1 to 10, preferably an integer of 1 to 6, and particularly preferably an integer of 2 to 4. r3 and r4 each independently represents an integer of 0 to 10, preferably an integer of 1 to 6, and particularly preferably an integer of 2 to 4. p represents an integer of 5 to 500, preferably 8 to 350, and particularly preferably 10 to 250.

  Commercially available macroazo initiators “VPS-0501” and “VPS-1001” {trade name; manufactured by Wako Pure Chemical Industries, Ltd.} have several units within the general formula (3) via the azo group. It is a linked compound, and the unit can be introduced into the polymer obtained by polymerizing the compound as an initiator, which is preferable.

  The structural unit containing the polysiloxane structure is preferably introduced in a range of 0.01 to 20% by mass, more preferably in a range of 0.05 to 15% by mass in the fluoropolymer used in the present invention. It is a case where it introduce | transduces by (10), Especially preferably, it is a case where it introduce | transduces in 0.5-10 mass%.

  By introducing the polysiloxane structure, the film is imparted with antifouling and dustproof properties, and the film surface is also provided with slipperiness, which is advantageous for scratch resistance.

[Other polymer units]
The copolymer component that forms a polymer unit other than the above can be appropriately selected from various viewpoints such as hardness, adhesion to a substrate, solubility in a solvent, transparency, and the like. For example, methyl vinyl ether, ethyl vinyl ether Examples thereof include vinyl ethers such as t-butyl vinyl ether, n-butyl vinyl ether, cyclohexyl vinyl ether and isopropyl vinyl ether, and vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate and vinyl cyclohexanecarboxylate. The introduction amount of these copolymerization components is in the range of 0 to 40 mol%, preferably in the range of 0 to 30 mol%, particularly preferably in the range of 0 to 20 mol%.

[Preferred form of fluoropolymer]
The form of the fluorine-containing polymer (A) particularly preferred in the present invention is a form represented by the following general formula (3).
General formula (3):

In the general formula (3), Rf ¹⁰ represents a perfluoroalkyl group having 1 to 5 carbon atoms. With respect to the monomer constituting the site represented by —CF ₂ CF (Rf ¹⁰ ) —, the above description applies as an example of perfluoroolefin. Rf ¹² has the same definition as described in the fluorine-containing vinyl ether (Rf ¹² in the compound represented by the general formula M2), and the preferred range is also the same. Rf ¹¹ has the same definition as described for another fluorine-containing vinyl ether (Rf ¹¹ in the compound represented by the general formula M1), and the preferred range is also the same.

A ³¹ and B ³¹ each represent a hydroxyl group-containing vinyl monomer polymerization unit and an arbitrary constituent unit. A ³¹ is the same as the definition of the hydroxyl group-containing vinyl monomer polymerization unit (b) described above, and B ³¹ is not particularly limited, but vinyl ethers and vinyl esters are more preferable from the viewpoint of copolymerization. . Specific examples include the monomers exemplified in the above [Other polymerized units].

Y ³¹ represents a structural unit having a polysiloxane structure, and the form thereof may be a polymer unit having a graft site containing a polysiloxane repeating unit represented by the general formula (1) in the side chain. May contain a polysiloxane repeating unit represented by the general formula (1). Their definitions and preferred ranges are the same as those described in the above [Structural unit (c) or (d) having a polysiloxane structure].

  a to d each represent a molar fraction (%) of each constituent component, and a + b1 + b2 + c + d = 100. 30 ≦ a ≦ 70 (more preferably 30 ≦ a ≦ 60, more preferably 35 ≦ a ≦ 60), 0 ≦ b1 ≦ 40 (more preferably 0 ≦ b ≦ 30, still more preferably 0 ≦ b1 ≦ 20). 0 ≦ b2 ≦ 40 (more preferably 0 ≦ b2 ≦ 30, still more preferably 0 ≦ b2 ≦ 20), 20 <c ≦ 70 (more preferably 25 ≦ c ≦ 60, still more preferably 25 ≦ c ≦ 55) , 0 ≦ d ≦ 40 (more preferably 0 ≦ d ≦ 30) is satisfied.

  y represents a mass fraction (%) of the structural unit containing a polysiloxane structure with respect to the entire fluoropolymer, and 0.01 ≦ y ≦ 20 (more preferably 0.05 ≦ y ≦ 15, and still more preferably 0.8. 5 ≦ y ≦ 10) is satisfied.

  The number average molecular weight of the fluorine-containing polymer used for forming the low refractive index layer in the curable composition of the present invention is preferably 3,000 to 1,000,000, more preferably 5,000 to 500,000. Especially preferably, it is 7,000 to 100,000.

  Here, the number average molecular weight was determined using a solvent tetrahydrofuran (THF) by a GPC analyzer using a column of “TSKgel GMHxL”, “TSKgel G4000HxL”, “TSKgel G2000HxL” (both trade names manufactured by Tosoh Corporation), The molecular weight is expressed in terms of polystyrene by differential refractometer detection.

Specific examples of the fluorine-containing polymer (A) useful in the present invention are shown in Tables 1 and 2, but the present invention is not limited thereto. In Tables 1 and 2, they are expressed as combinations of polymerized units.

In the table, the molar ratio of each component is shown for the fluorine-containing polymer component. The abbreviations are as follows.
HFP: hexafluoropropylene,
M1- (1): The following structural formula

  M1- (2): Structural formula below

  M2- (3): heptafluoropropyl trifluorovinyl ether,

HEVE: 2-hydroxyethyl vinyl ether,
HBVE: 4-hydroxybutyl vinyl ether,
HOVE: 8-hydroxyoctyl vinyl ether,
DEGVE: Diethylene glycol vinyl ether,
HMcHVE: 4- (hydroxymethyl) cyclohexylmethyl vinyl ether,
EVE: ethyl vinyl ether,
cHVE: cyclohexyl vinyl ether,
tBuVE: t-butyl vinyl ether,
VAc: vinyl acetate.

Regarding the component containing the polysiloxane structure, the name of the polysiloxane structure-containing component used in the synthesis reaction and the mass% of the polysiloxane structure-containing component in the entire polymer are shown. The abbreviations are as follows.
FM-0721: “Silaplane FM-0721” {manufactured by Chisso Corporation}
FM-0725: "Silaplane FM-0725" (same as above)
VPS-1001: “macroazo initiator VPS-1001” {Wako Pure Chemical Industries, Ltd.}
VPS-0501: “macroazo initiator VPS-0501” (same as above)

[Synthesis of fluoropolymer]
The fluoropolymer (A) used in the present invention can be synthesized by various polymerization methods such as solution polymerization, precipitation polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization. Moreover, it is compoundable by well-known operations, such as a batch type, a semi-continuous type, and a continuous type.

  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 described in, for example, the revised version of Tsuruta Junji “Polymer Synthesis Method” (published by Nikkan Kogyo Shimbun, 1971), Takatsu Otsu and Masato Kinoshita, “Experimental Methods for Polymer Synthesis” , Published in 1972, pages 124-154.

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

  The polymerization temperature needs to be set in relation to the molecular weight of the polymer to be produced, the type of initiator, etc., and can be from 0 ° C. or lower to 100 ° C. or higher, but it is preferable to perform polymerization in the range of 40 to 100 ° C. .

  The reaction pressure can be appropriately selected, but is usually 0.01 to 10 MPa, preferably 0.05 to 5 MPa, more preferably about 0.1 to 2 MPa. The reaction time is about 5 to 30 hours.

  The obtained polymer can be used as it is for the use in the present invention, or can be purified by reprecipitation or liquid separation operation.

[Crosslinking agent (B)]
The curable composition of this invention contains the fluorine-containing polymer (A) containing a hydroxyl group, and the compound (crosslinking agent) (B) which can react with the hydroxyl group in this fluorine-containing polymer. The crosslinking agent preferably has two or more sites that react with hydroxyl groups, and more preferably has four or more sites.

  The structure of the crosslinking agent (B) is not particularly limited as long as it has the above-mentioned number of functional groups capable of reacting with hydroxyl groups. For example, polyisocyanates, partial condensates of isocyanate compounds, multimers, polyhydric alcohols, Examples include adducts with molecular weight polyester films, blocked polyisocyanate compounds in which isocyanate groups are blocked with a blocking agent such as phenol, aminoplasts, polybasic acids or anhydrides, polyepoxy compounds, polyoxetanyl compounds, and the like. it can.

[Aminoplasts]
Among these, in the present invention, aminoplasts that undergo a crosslinking reaction with a hydroxyl group-containing compound under acidic conditions are preferable from the viewpoints of both stability during storage and the activity of the crosslinking reaction, and the strength of the formed film. Aminoplasts contain an amino group capable of reacting with a hydroxyl group present in the fluorine-containing polymer, that is, a hydroxyalkylamino group or an alkoxyalkylamino group, or a carbon atom adjacent to a nitrogen atom and substituted with an alkoxy group. A compound. Specific examples include melamine compounds, urea compounds, benzoguanamine compounds, and the like.

  The melamine compounds are generally known as compounds having a skeleton in which a nitrogen atom is bonded to a triazine ring, and specific examples include melamine, alkylated melamine, methylol melamine, and alkoxylated methyl melamine. . In particular, methylolated melamine and alkoxylated methyl melamine obtained by reacting melamine and formaldehyde under basic conditions and derivatives thereof are preferable, and alkoxylated methyl melamine is particularly preferable in view of storage stability. There are no particular restrictions on methylolated melamine and alkoxylated methylmelamine. For example, use of various resins obtained by the method described in “Plastic Materials Course [8] Urea Melamine Resin” (Nikkan Kogyo Shimbun) Is also possible.

As the urea compound, in addition to urea, an alkoxylated methylurea which is a polymethylolated urea derivative thereof, and a compound having a glycoluril skeleton or a 2-imidazolidinone skeleton having a cyclic urea structure are also preferable. As for the amino compounds such as the urea derivatives, various resins described in the above-mentioned “Yurea / Melamine resin” can be used.

  As a compound suitably used as a crosslinking agent in the present invention, a melamine compound or a glycoluril compound is particularly preferable from the viewpoint of compatibility with a fluorine-containing polymer, and among these, from the viewpoint of reactivity, the crosslinking agent is nitrogen in the molecule. A compound containing two or more carbon atoms containing an atom and substituted with an alkoxy group adjacent to the nitrogen atom is preferred.

Particularly preferred compounds are compounds having structures represented by the following structural formulas (H-1) and (H-2), and partial condensates thereof. In the formula, R ⁴¹ represents an alkyl group having 1 to 6 carbon atoms or a hydroxyl group. Note that a plurality of R ⁴¹ present in the same compound may be the same or different.
Structural formulas (H-1) and (H-2):

  The amount of aminoplast added to the fluoropolymer (A) is 1 to 70 parts by mass, preferably 3 to 60 parts by mass, more preferably 5 to 50 parts by mass, per 100 parts by mass of the fluoropolymer. is there. If it is 1 part by mass or more, the durability as a thin film can be more fully exhibited, and if it is 70 parts by mass or less, the low refractive index of the low refractive index layer can be maintained when used for optical applications. preferable. From the viewpoint of keeping the refractive index low even when a cross-linking agent is added, a cross-linking agent having a small increase in refractive index even when added is preferable, and from this viewpoint, among the above compounds, a skeleton represented by (H-2) More preferred are compounds having

[Curing catalyst]
The curable composition of the present invention generates an acid by irradiation with ionizing radiation and promotes a crosslinking reaction between the hydroxyl group of the fluorine-containing polymer and the crosslinking agent. In the present invention, a compound that generates an acid upon irradiation with ionizing radiation such as light (hereinafter also referred to as a photosensitive acid generator) (C) is used. This will be described below.

[Photosensitive acid generator (C)]
The photosensitive acid generator (C) used in the present invention imparts photosensitivity to the curable composition, and photocures the coating film formed from the curable composition by, for example, irradiation with radiation. It is a substance that makes it possible.

  As a typical photosensitive acid generator (C), for example, “JOEM HANDBOOK 3 Organic Materials for Imaging” edited by Organic Electronics Materials Research Group (Bunshin Publishing) p. 63-88, and p. Various examples are described in JP-A Nos. 149 to 156, JP-A-10-282644, JP-A-10-339947, and JP-A-11-30856, and these known compounds can be used.

Specifically, (1) iodonium salts, sulfonium salts, phosphoniums having RSO ₃ ⁻ (wherein R represents an alkyl group or aryl group), AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ , BF ₄ ^{−, and the} like as anions. Various onium salts such as salts, diazonium salts, ammonium salts, pyridinium salts; (2) sulfone compounds such as β-ketoesters, β-sulfonylsulfones and their α-diazo compounds; (3) alkylsulfonic acid esters, haloalkylsulfones Sulfonic acid esters such as acid esters, aryl sulfonic acid esters and imino sulfonates; (4) sulfonimide compounds; (5) diazomethane compounds; (5) organic compounds such as oxazole derivatives and s-triazine derivatives having a trihalomethyl group Halide: (6) o-nitrobenzyl ester of organic acid, benzo N'esuteru, imino ester; other can be cited, can be appropriately used. Among them, (1) onium salts are preferable, and (1) sulfonium salt or iodonium salt is particularly preferable.
Although the specific example is shown below, it is not limited to these.

  The photosensitive acid generator (C) can be used alone or in combination of two or more. The use ratio of the photosensitive acid generator is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the fluoropolymer (A) in the curable composition. is there. If the ratio of the photosensitive acid generator is less than or equal to the upper limit, it is preferable because the resulting cured film has excellent strength and good transparency. Moreover, when the sensitivity with respect to the ionizing radiation to irradiate is low, you may use a sensitizer suitably.

[Thermal acid generator]
In the present invention, the curable composition is applied and dried, and then irradiated with light to generate an acid to be cured. For the purpose of further proceeding the curing reaction, a compound that generates an acid by heat (hereinafter also referred to as a thermal acid generator) may be added. Such a thermal acid generator is preferably a salt composed of an acid and an organic base described below.

(acid)
Examples of the acid include organic acids such as sulfonic acid, phosphonic acid and carboxylic acid, and inorganic acids such as sulfuric acid and phosphoric acid. From the viewpoint of high ability to catalyze the curing reaction and pKa from the viewpoint of compatibility with the polymer. Organic acids having a low C are more preferred, sulfonic acids and phosphonic acids are more preferred, and sulfonic acids are most preferred. Preferred sulfonic acids include p-toluenesulfonic acid (PTS), benzenesulfonic acid (BS), p-dodecylbenzenesulfonic acid (DBS), p-chlorobenzenesulfonic acid (CBS), 1,4-naphthalenedisulfonic acid (NDS). ), Methanesulfonic acid (MsOH), nonafluorobutane-1-sulfonic acid (NFBS), etc., and any of them can be preferably used {the abbreviation in parentheses}.

(Organic base)
In the curing catalyst, the acid generation efficiency during heating varies greatly depending on the type of organic base combined with the acid. That is, the lower basicity of the organic base, and the lower the boiling point, the higher the acid generation efficiency during heating, which is preferable from the viewpoint of curing activity. However, if the basicity is too low, and the boiling point is too low, the organic base is stored. Stability is insufficient. Accordingly, it is preferable to use an organic base having an appropriate basicity and boiling point. When expressed using pKa of a conjugate acid as a basic index, the pKa of the organic base used in the present invention needs to be 5.0 to 13.0, and should be 5.0 to 11.0. Preferably, it is 6.0 to 10.5, more preferably 6.5 to 10.0.

  The pKa value of the organic base is described in II-334-340 of Volume 2 of the Chemical Handbook Basic Edition (5th revised edition, edited by The Chemical Society of Japan, Maruzen, 2004), Volume 2. Among them, an organic base having an appropriate pKa can be selected. Further, a compound that can be presumed to have a structurally appropriate pKa even if not described in the “Chemical Handbook” can be preferably used.

  Further, the boiling point of the base is preferably 120 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 70 ° C. or lower. Here, the boiling point represents the boiling point at 1013 hPa. By setting the boiling point of the organic base within the above range, the acid generation efficiency can be increased and desired curing activity can be obtained. Furthermore, the lower boiling point within the above range is preferable from the viewpoint of higher acid generation efficiency during heating and higher curing activity.

  When used as an acid catalyst in the present invention, a salt composed of the above acid and an organic base may be isolated and used, or a salt may be formed in a solution by mixing the acid and the organic base, and the solution may be used. . Moreover, only one kind of acid or organic base may be used, or a plurality of kinds may be mixed and used. When the acid and the organic base are mixed and used, it is preferable that the equivalent ratio of the acid and the organic base is 1: 0.9 to 1.5, preferably 1: 0.95 to 1.3. Is more preferable, and 1: 1.0 to 1.1 is preferable.

  The ratio of the thermal acid generator used is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, and still more preferably 100 parts by mass of the fluoropolymer in the curable composition. Is 0.2-3 parts by mass.

[Compound having a polysiloxane structure]
The curable composition of the present invention has a polysiloxane structure for the purpose of further improving scratch resistance and imparting antifouling properties by imparting slipperiness to the coating film formed thereby. A compound may be used. Next, the compound having such a polysiloxane structure will be described.

  There is no restriction | limiting in particular in the structure of a compound, The thing which has a substituent in the terminal and / or side chain of a compound chain | strand which contains multiple dimethylsilyloxy units as a repeating unit is preferable. The compound chain containing dimethylsilyloxy as a repeating unit may contain a structural unit other than dimethylsilyloxy.

  Although there is no restriction | limiting in particular in the molecular weight of the compound which has a polysiloxane structure, It is preferable that it is 100,000 or less, It is especially preferable that it is 50,000 or less, It is most preferable that it is 3000-30000.

From the viewpoint of maintaining the slipperiness and antifouling effect of the coating film formed by coating a curable composition containing a compound having a polysiloxane structure, and improving the scratch resistance, and transferring From the standpoint of prevention, the compound preferably contains a hydroxyl group, a functional group that reacts with the hydroxyl group to form a bond, or a functional group that reacts with the crosslinking agent to form a bond. This bond formation reaction preferably proceeds rapidly under heating conditions and / or in the presence of a catalyst.
Examples of the functional group that forms a bond by reacting with a hydroxyl group include an epoxy group and a carboxyl group.
The functional group capable of reacting with the crosslinking agent to form a bond may be a nucleophilic functional group, and examples thereof include a hydroxyl group, an epoxy group, a carboxyl group, and an amino group.

  Examples of the compound having a preferred polysiloxane structure include, but are not limited to, the following.

[Containing hydroxyl group]
“X-22-160AS”, “KF-6001”, “KF-6002”, “KF-6003”, “X-22-170DX”, “X-22-176DX”, “X-22-176D”, “X-22-176F” {manufactured by Shin-Etsu Chemical Co., Ltd.}; “FM-4411”, “FM-4421”, “FM-4425”, “FM-0411”, “FM-0421”, “ "FM-0425", "FM-DA11", "FM-DA21", "FM-DA25" {above, manufactured by Chisso Corp.}; "CMS-626", "CMS-222" {above, manufactured by Gelest} .

[Containing epoxy group or carboxyl group]
"X-22-162C", "KF-105" {manufactured by Shin-Etsu Chemical Co., Ltd.}; "FM-5511", "FM-5521", "FM-5525", "FM-6611", " FM-6621 "," FM-6625 "," DMS-B21 "," DMS-B25 "," DMS-B31 "{above, manufactured by Chisso Corporation}.

[Containing amino groups]
“KF-8010”, “X-22-161A”, “X-22-161B”, “KF-105” (manufactured by Shin-Etsu Chemical Co., Ltd.), “DMS-A15”, “DMS-A21”, “DMS-A32”, “AMS-132”, “AMS-152”, “AMS-162”, “AMS-242”, “ATM-1112”, “ATM-1322” [manufactured by Chisso Corporation].

  The addition amount of the compound having a polysiloxane structure is preferably 0.01 to 20% by mass, more preferably 0.05 to 15% by mass with respect to the fluorine-containing polymer, and 0.1 to 10%. More preferably, it is mass%.

[Other substances contained in the curable composition]
When the curable composition of the present invention is used to form a low refractive index layer of an antireflection film, the aforementioned fluoropolymer (A), a crosslinking agent (B) capable of reacting with a hydroxyl group, a curing catalyst, In addition to the compound (C) that generates an acid upon irradiation with ionizing radiation and having a polysiloxane structure used as necessary, inorganic fine particles, organosilane compounds, and other various additives are added. Further, it is prepared by dissolving these in a suitable solvent. Under the present circumstances, although the density | concentration of solid content of a curable composition is suitably selected according to a use, generally it is about 0.01-60 mass%, Preferably it is 0.5-50 mass%, Especially preferably, it is about 1-20 mass%.

[Inorganic fine particles]
When the curable composition of the present invention is used for forming the low refractive index layer of the antireflective film, the blending amount of the inorganic fine particles in the low refractive index layer is preferably 1 to 100 mg / m ² , more preferably 5 It is -80 mg / m < ² >, More preferably, it is 10-60 mg / m < ² >. If the blending amount of the inorganic fine particles is equal to or higher than the lower limit value, the effect of improving the scratch resistance is remarkable, and if it is equal to or lower than the upper limit value, fine irregularities are formed on the surface of the low refractive index layer, black tightening, etc. Therefore, it is preferable to be within this range.

  Since the inorganic fine particles are contained in the low refractive index layer, it is desirable that the inorganic fine particles have a low refractive index. Examples thereof include fine particles of magnesium fluoride and silica. In particular, silica fine particles are preferable in terms of refractive index, dispersion stability, and cost.

  The size of these inorganic fine particles is preferably 1 to 200 nm, more preferably 5 to 90 nm. If the particle size of the inorganic fine particle is equal to or greater than the lower limit, the effect of improving the scratch resistance is increased. If the particle size is equal to or smaller than the upper limit, fine irregularities are formed on the surface of the low refractive index layer, and black tightening, etc. Therefore, it is preferable to be within this range.

The inorganic fine particles may be either crystalline or amorphous, and may be monodispersed particles or aggregated particles as long as a predetermined particle size is satisfied. The shape is most preferably a spherical diameter, but there is no problem even if the shape is indefinite.

[Organosilane compound]
When the curable composition of the present invention is used for forming a low refractive index layer, the composition may be formed from a curable composition further containing an organosilane compound. The definition of the organosilane compound and the structure of the preferred compound are the same as those described in paragraph numbers [0131] to [0132] of JP-A No. 2004-331812.

[Other additives]
Furthermore, when the curable composition of the present invention is used for forming a low refractive index layer, the composition is polyfunctional (meth) from the viewpoint of interfacial adhesion with the lower layer directly in contact with the low refractive index layer. A small amount of a crosslinking agent other than those described above, such as an acrylate compound or a polyfunctional epoxy compound, can also be added. When adding these, it is preferable to set it as the range of 30 mass% or less with respect to the total solid of a low-refractive-index layer film, It is more preferable to set it as the range of 20 mass% or less, The range of 10 mass% or less It is particularly preferable that

  Further, for the purpose of imparting characteristics such as water resistance and chemical resistance, and for the purpose of further enhancing the antifouling property and slipperiness, in addition to the compound having the polysiloxane structure, known silicone compounds Alternatively, a fluorine compound antifouling agent, a slipping agent, and the like can be appropriately added. When these additives are added, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the curable composition, more preferably in the range of 0.05 to 10% by mass. Particularly preferably 0.1 to 5% by mass.

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

  It is preferable that the fluorine-based compound further has a substituent that contributes to bond formation or compatibility with the low refractive index layer film. The substituents may be the same or different, and a plurality of substituents are preferable. Examples of preferred substituents include acryloyl group, methacryloyl group, vinyl group, aryl group, cinnamoyl group, epoxy group, oxetanyl group, hydroxyl group, polyoxyalkylene group, carboxyl group, amino group and the like. The fluorine-based compound may be a polymer or an oligomer with a compound not containing a fluorine atom, and the molecular weight is not particularly limited.

  Although there is no restriction | limiting in particular in fluorine atom content in a fluorine-type compound, It is preferable that it is 20 mass% or more, It is especially preferable that it is 30-70 mass%, It is most preferable that it is 40-70 mass%. .

Examples of preferred fluorine-based compounds include “R-2020”, “M-2020”, “R-3833”, “M-3833” (all trade names) manufactured by Daikin Chemical Industries, Ltd .; "Megafuck F-171", "Megafuck F-172", "Megafuck F-179A", "Defenser MCF-300" (above product names), etc. manufactured by Co., Ltd. are mentioned, but are not limited thereto. It is not a thing.

(Dustproofing agent, antistatic agent, etc.)
The curable composition for forming the low refractive index layer is further provided with a dust-proofing agent such as a known cationic surfactant or polyoxyalkylene-based compound for the purpose of imparting properties such as dust resistance and antistatic property, and antistatic property. An agent or the like can also be added as appropriate. As for these dustproof agent and antistatic agent, the structural unit may be included in the silicone-based compound or the fluorine-based compound as a part of the function.

  When these are added as additives, it is preferably added in the range of 0.01 to 20% by mass of the total solid content of the curable composition, more preferably in the range of 0.05 to 10% by mass. Particularly preferably 0.1 to 5% by mass.

  Examples of preferable compounds include “Megafac F-150” (trade name) manufactured by Dainippon Ink Co., Ltd., “SH-3748” (trade name) manufactured by Toray Dow Corning Co., Ltd., and the like. It is not limited.

〔solvent〕
In the present invention, the solvent used in the curable composition, particularly the curable composition used as the coating liquid for forming the low refractive index layer, can dissolve or disperse each component, coating process, drying Various solvents selected from the viewpoints of easily forming a uniform surface in the process, ensuring liquid storage stability, having an appropriate saturated vapor pressure, and the like can be used. From the viewpoint of drying load, it is preferable that a solvent having a boiling point of 100 ° C. or lower at normal pressure and room temperature as a main component and a small amount of a solvent having a boiling point of 100 ° C. or higher for adjusting the drying speed.

  Examples of the solvent having a boiling point of 100 ° C. or lower include hydrocarbons such as hexane (boiling point 68.7 ° C.), heptane (98.4 ° C.), cyclohexane (80.7 ° C.), and benzene (80.1 ° C.); Halogenated carbonization such as dichloromethane (39.8 ° C), chloroform (61.2 ° C), carbon tetrachloride (76.8 ° C), 1,2-dichloroethane (83.5 ° C), trichloroethylene (87.2 ° C) Hydrogen; ethers such as diethyl ether (34.6 ° C.), diisopropyl ether (68.5 ° C.), dipropyl ether (90.5 ° C.), tetrahydrofuran (66 ° C.); ethyl formate (54.2 ° C.), Esters such as methyl acetate (57.8 ° C.), ethyl acetate (77.1 ° C.), isopropyl acetate (89 ° C.); acetone (56.1 ° C.), 2-butanone (methyl ethyl) Ketones such as 79.6 ° C., the same as ketone; methanol (64.5 ° C.), ethanol (78.3 ° C.), 2-propanol (82.4 ° C.), 1-propanol (97.2 ° C.), etc. Alcohols; cyano compounds such as acetonitrile (81.6 ° C.) and propionitrile (97.4 ° C.); carbon disulfide (46.2 ° C.) and the like. Of these, ketones and esters are preferable, and ketones are particularly preferable. Among the ketones, 2-butanone is particularly preferable.

  Examples of the solvent having a boiling point of 100 ° C. or more include, for example, octane (125.7 ° C.), toluene (110.6 ° C.), xylene (138 ° C.), tetrachloroethylene (121.2 ° C.), and chlorobenzene (131.7 ° C.). , Dioxane (101.3 ° C.), dibutyl ether (142.4 ° C.), isobutyl acetate (118 ° C.), cyclohexanone (155.7 ° C.), 2-methyl-4-pentanone {same as methyl isobutyl ketone (MIBK), 115.9 ° C.}, 1-butanol (117.7 ° C.), N, N-dimethylformamide (153 ° C.), N, N-dimethylacetamide (166 ° C.), dimethyl sulfoxide (189 ° C.) and the like. Cyclohexanone and 2-methyl-4-pentanone are preferable.

<Film having a layer of cured product and film-like cured product>
The curable composition of the present invention can be applied to a thin layer and cured to obtain a film-like cured product, which is useful for a protective layer of a substrate, for example. Moreover, the film which has a layer of a film-form hardened | cured material can be obtained by coating and hardening this curable composition on a transparent support body. In particular, the curable composition of the present invention is useful as a coating solution for a low refractive index layer of an antireflection film. The antireflection film in which the composition of the present invention is particularly useful will be described below.

<Antireflection film>
The antireflection film of the present invention is characterized by having a low refractive index layer formed by coating the above-described curable composition of the present invention on a transparent support.

[Basic structure of antireflection film]
The antireflective film of the present invention has a hard coat layer, which will be described later, together with a low refractive index layer, which is an indispensable optical layer, on a transparent substrate, and has a reflectivity due to optical interference thereon. The layers are laminated in consideration of the refractive index, film thickness, number of layers, layer order, and the like so as to decrease.

  In the simplest configuration, the low-reflection antireflection film has a configuration in which only a low refractive index layer is coated on a substrate. In order to further reduce the reflectance, the antireflection layer is preferably constituted by combining a high refractive index layer having a higher refractive index than that of the base material and a low refractive index layer having a lower refractive index than that of the base material. Examples of configurations include two layers of a high refractive index layer / low refractive index layer from the base material side, and three layers having different refractive indices, a medium refractive index layer (having a higher refractive index than the base material or the hard coat layer). , A layer having a refractive index lower than that of a high refractive index layer) / a layer having a high refractive index / a layer having a low refractive index, and the like.

The example of the preferable layer structure of the antireflection film of this invention is shown below. In the following configuration, the base film functions as a support.
・ Base film / low refractive index layer,
・ Base film / Antistatic layer / Low refractive index layer,
・ Base film / Anti-glare layer / Low refractive index layer,
Base film / antiglare layer / antistatic layer / low refractive index layer,
・ Described film / antistatic layer / antiglare layer / low refractive index layer,
・ Base film / hard coat layer / antiglare layer / low refractive index layer,
・ Base film / hard coat layer / antiglare layer / antistatic layer / low refractive index layer,
・ Base film / hard coat layer / antistatic layer / antiglare layer / low refractive index layer,
・ Base film / hard coat layer / high refractive index layer / low refractive index layer,
・ Base film / hard coat layer / antistatic layer / high refractive index layer / low refractive index layer,
Base film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antiglare layer / high refractive index layer / low refractive index layer,
Base film / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antistatic layer / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / hard coat layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Base film / antistatic layer / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / antiglare layer / medium refractive index layer / high refractive index layer / low refractive index layer,
Antistatic layer / base film / antiglare layer / high refractive index layer / low refractive index layer / high refractive index layer / low refractive index layer.

As long as the reflectance can be reduced by optical interference, it is not limited to these layer configurations. The high refractive index layer may be a light diffusing layer having no antiglare property. The antistatic layer is preferably a layer containing conductive polymer particles or metal oxide fine particles (for example, ATO, ITO), and can be provided by coating or atmospheric pressure plasma treatment.

  Next, as an embodiment of the present invention, a basic configuration of a suitable antireflection film will be described with reference to the drawings.

  The cross-sectional view schematically shown in FIG. 1A is an example of the antireflection film of the present invention. The antireflection film 1 a has a layer structure in the order of a transparent support 2, a hard coat layer 3, an antiglare hard coat layer 4, and a low refractive index layer 5.

  Matte particles (not shown) are dispersed in the antiglare hard coat layer 4, and the refractive index of the material other than the matte particles of the antiglare hard coat layer 4 is in the range of 1.48 to 2.00. Preferably, it is in the range of 1.50 to 1.80. The refractive index of the low refractive index layer 5 is preferably in the range of 1.20 to 1.47, more preferably in the range of 1.30 to 1.44.

  In the present invention, the hard coat layer may be a hard coat layer having an antiglare property as described above, a hard coat layer having no antiglare property, or a single layer, or a plurality of layers, for example, 2 to 4 layers. It may be comprised. Alternatively, the hard coat layer may be omitted. Accordingly, the hard coat layer 3 and the antiglare hard coat layer 4 shown in FIG. 1 are not essential, but any one of these hard coat layers is preferably applied to impart film strength. The low refractive index layer is coated on the outermost layer.

  The cross-sectional view schematically shown in FIG. 1B is an example of the antireflection film of the present invention. The antireflection film 1b includes a transparent support 2, a hard coat layer 3, a medium refractive index 7, and a high refractive index. It has a layer structure in the order of layer 8 and low refractive index layer (outermost layer) 5. The transparent support 2, the middle refractive index layer 7, the high refractive index layer 8, and the low refractive index layer 5 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 layer structure as shown in FIG. 1B, as described in JP-A-59-50401, the medium refractive index layer is represented by the following mathematical formula (1), and the high refractive index layer is represented by the following mathematical formula (2). It is preferable that the low refractive index layer satisfies the following formula (3) in that an antireflection film having more excellent antireflection performance can be produced.

Formula (1): (hλ / 4) × 0.7 <n ₁ d ₁ <(hλ / 4) × 1.3
Formula (2): (iλ / 4) × 0.7 <n ₂ d ₂ <(iλ / 4) × 1.3
Formula (3): (jλ / 4) × 0.7 <n ₃ d ₃ <(jλ / 4) × 1.3

In formulas (1) to (3), h is a positive integer (generally 1, 2 or 3), i is a positive integer (typically 1, 2 or 3), and j is a positive odd number (generally 1). ). n ₁ , n ₂ and n ₃ are the refractive indexes of the medium refractive index layer, the high refractive index layer and the low refractive index layer, respectively, and d ₁ , d ₂ and d ₃ are the medium refractive index layer, the high refractive index layer and the high refractive index layer, respectively. It is the layer thickness (nm) of the refractive index layer and the low refractive index layer. Here, λ is a design wavelength for which the reflectance is desired to be reduced. When the antireflection film is used for a normal display surface, λ is the wavelength (nm) of visible light, and is a value in the range of 380 to 680 nm. In particular, an antireflection film having a low luminous reflectance can be designed by setting λ in the range of 500 to 550 nm, which has a high human visual sensitivity.

  In the layer configuration as shown in FIG. 1B, the medium refractive index layer is represented by the following mathematical formula (1-1), the high refractive index layer is represented by the following mathematical formula (2-1), and the low refractive index layer is represented by the following mathematical formula (3-1). It is particularly preferable that each of these is satisfied. Here, λ is 500 nm, h is 1, i is 2, and j is 1.

Formula (1-1): (hλ / 4) × 0.80 <n ₁ d ₁ <(hλ / 4) × 1.00
Formula (2-1): (iλ / 4) × 0.75 <n ₂ d ₂ <(iλ / 4) × 0.95
Formula (3-1): (jλ / 4) × 0.95 <n ₃ d ₃ <(jλ / 4) × 1.05

  The high refractive index, medium refractive index, and low refractive index described here refer to the relative refractive index between layers. Moreover, in FIG.1 (b), the high refractive index layer is used as a light interference layer, and the antireflection film which has the very outstanding antireflection performance can be produced.

(Low refractive index layer)
Next, the low refractive index layer in the antireflection film of the present invention will be described below.

  The refractive index of the low refractive index layer in the present invention is preferably 1.20 to 1.47, more preferably 1.30 to 1.44. The thickness of the low refractive index layer is preferably from 50 nm to 400 nm, more preferably from 60 nm to 150 nm, and most preferably from 60 nm to 130 nm.

Furthermore, as described above, the low refractive index layer preferably satisfies the following formula (3) from the viewpoint of reducing the reflectance.
Formula (3): (jλ / 4) × 0.7 <n ₃ d ₃ <(jλ / 4) × 1.3

In Equation (3), j is a positive odd number, and n ₃ and d ₃ are the refractive index and film thickness (nm) of the low refractive index layer, respectively, as described above. Here, λ is a design wavelength for which the reflectance is desired to be reduced. In particular, an antireflection film having a low luminous reflectance can be designed by setting λ in the range of 500 to 550 nm, which has a high human visual sensitivity.
In addition, satisfy | filling said Numerical formula (3) means that j (positive odd number, usually 1) which satisfy | fills Numerical formula (3) exists in the said wavelength range.

  As described above, the low refractive index layer in the present invention comprises at least the curable composition of the present invention, that is, (A) the fluorine-containing vinyl monomer polymerization unit (a) and the hydroxyl group-containing vinyl monomer polymerization unit (b), respectively. At least one fluorine-containing polymer containing one by one and the proportion of the polymerized units (b) exceeding 20 mol%, (B) at least one crosslinking agent capable of reacting with a hydroxyl group, and (C) ionizing radiation It is formed by coating a curable composition containing at least one compound that generates an acid upon irradiation on a transparent substrate.

The low refractive index layer of the film of the present invention can be formed by the following coating method, but is not limited to this method.
First, a coating solution containing components for forming a low refractive index layer is prepared. Using the obtained coating solution, dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method and extrusion coating method (see US Pat. No. 2,681,294) Apply on a transparent support, heat and dry. Of these coating methods, the gravure coating method is preferable because a coating solution with a small coating amount can be applied with high film thickness uniformity as in the case of forming each layer of the antireflection film. Among the gravure coating methods, the micro gravure method is more preferable because of high film thickness uniformity.

  The micro gravure coating method used in the present invention is a gravure roll having a diameter of about 10 to 100 mm, preferably about 20 to 50 mm and engraved with a gravure pattern on the entire circumference, below the support and in the transport direction of the support. The surface of the gravure roll is reversely rotated, and the excess coating liquid is scraped off from the surface of the gravure roll by a doctor blade, so that a substantially constant amount of the coating liquid is removed from the lower surface of the support at a position where the upper surface of the support is in a free state. This is a coating method in which the film is transferred and coated. A roll-shaped transparent support is continuously unwound, and the low refractive index layer is formed on one side of the unwound support by applying the curable composition of the present invention by a microgravure coating method. Can be obtained.

  As coating conditions by the micro gravure coating method, the number of gravure patterns imprinted on the gravure roll is preferably 50 to 800 lines / inch, more preferably 100 to 300 lines / inch, and the depth of the gravure pattern is 1 to 600 μm. Is preferable, 5 to 200 μm is more preferable, the rotation speed of the gravure roll is preferably 3 to 800 rpm, more preferably 5 to 200 rpm, and the conveyance speed of the support is 0.5 to 100 m / min. It is preferably 1 to 50 m / min.

  In order to supply the film of the present invention with high productivity, an extrusion method (die coating method) is preferably used. Since the die coating method is a pre-measuring method, the film thickness control is relatively easy, and further, the evaporation of the solvent in the coating part is small, which is preferable.

  After drying the solvent, the film of the present invention is passed through a zone where the coating film is cured by ionizing radiation and, if necessary, heat, in the state of a web comprising a transparent support and a coating film formed thereon. The film can be cured. Depending on the material used, irradiation with ionizing radiation alone or in combination with thermosetting is also preferable.

The conditions for thermosetting are not particularly limited as long as the binder causes a crosslinking reaction, but are preferably 30 to 200 ° C., more preferably 35 to 130 ° C., and most preferably 40 to 120 ° C. The heat curing time varies depending on the composition of the curing component, catalyst type and amount, etc., but is 5 seconds to 1 hour, preferably 5 seconds to 30 minutes, and most preferably 10 seconds to 20 minutes.
Although there is no particular limitation on the method of bringing the film surface temperature of the film to a desired temperature, a method of heating a roll to contact the film, a method of spraying heated nitrogen, irradiation with far infrared rays or infrared rays is preferable. A method of flowing hot water or steam through a rotating metal roll described in Japanese Patent No. 2523574 can also be used. On the other hand, at the time of irradiation of ionizing radiation described below, when the film surface temperature of the film rises, a method of cooling the roll and bringing it into contact with the film can be used.

The ionizing radiation species in the present invention is not particularly limited, and is appropriately selected from ultraviolet rays, electron beams, near ultraviolet rays, visible light, near infrared rays, infrared rays, X-rays and the like according to the type of curable composition forming the film. Although it can be selected, ultraviolet rays and electron beams are preferred, and ultraviolet rays are particularly preferred because they are easy to handle and high energy can be easily obtained.
As the ultraviolet light source for photopolymerizing the ultraviolet reactive compound, any light source that generates ultraviolet light can be used. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. An ArF excimer laser, a KrF excimer laser, an excimer lamp, synchrotron radiation, or the like can also be used. Among these, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, and a metal halide lamp can be preferably used.

Moreover, an electron beam can be used similarly. As an electron beam, 50 to 1000 keV, preferably 100 to 100, emitted from various electron beam accelerators such as a cockroft Walton type, a bandegraph type, a resonance transformation type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type. 300 keV
An electron beam having the following energy can be exemplified.

The irradiation conditions vary depending on individual lamps, but the amount of light irradiated is preferably 10 mJ / cm ² or more, more preferably, a 50~10000mJ / cm ^2, particularly preferably 50~2000mJ / cm ^2. At that time, the irradiation distribution in the width direction of the web is preferably 50 to 100%, more preferably 80 to 100%, including both ends with respect to the central maximum irradiation.

In the present invention, at least one layer laminated on the support is irradiated with ionizing radiation and heated to a film surface temperature of 60 ° C. or more for 0.5 seconds or more from the start of irradiation with ionizing radiation, with an oxygen concentration of 10 volumes. It is preferable to cure by the step of irradiating ionizing radiation in an atmosphere of less than or equal to%.
It is also preferable to heat in an atmosphere having an oxygen concentration of 3% by volume or less simultaneously and / or continuously with ionizing radiation irradiation.
In particular, it is preferable that the low refractive index layer which is the outermost layer and has a small film thickness is cured by this method. The curing reaction is accelerated by heat, and a film having excellent physical strength and chemical resistance can be formed.

  The time for irradiating with ionizing radiation is preferably from 0.7 seconds to 60 seconds, more preferably from 0.7 seconds to 10 seconds. If it is 0.5 seconds or less, the curing reaction cannot be completed, and sufficient curing cannot be performed. Also, maintaining low oxygen conditions for a long time is not preferable because the equipment becomes large and a large amount of inert gas is required.

  The oxygen concentration is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound in an atmosphere of 6% by volume or less, more preferably 4% by volume or less, particularly preferably 2% by volume of oxygen. Hereinafter, it is most preferably 1% by volume or less. In order to reduce the oxygen concentration more than necessary, a large amount of inert gas such as nitrogen is required, which is not preferable from the viewpoint of production cost.

  Moreover, the curing rate (100-residual functional group content) of the layer below the low refractive index layer was set to a value less than 100%, and a low refractive index layer was provided thereon and cured by ionizing radiation and / or heat. If the lower layer has a higher curing rate than before the low refractive index layer is provided, the adhesion between the lower layer and the low refractive index layer is improved, which is preferable.

[Layers other than low refractive index layer]
[Film-forming binder]
In the present invention, as the main film-forming binder component of the film-forming composition for forming a layer other than the low refractive index layer, it is possible to use a compound having an ethylenically unsaturated group to improve film strength, coating solution stability, coating It is preferable in terms of membrane productivity. The main film-forming binder refers to one that accounts for 10% by mass or more of the film-forming components excluding inorganic particles. Preferably, they are 20 mass% or more and 100 mass% or less, More preferably, they are 30 mass% or more and 95 mass% or less.

  A polymer having a saturated hydrocarbon chain or a polyether chain as a main chain is preferable, and a polymer having a saturated hydrocarbon chain as a main chain is more preferable. As the binder polymer having a saturated hydrocarbon chain as the main chain and having a crosslinked structure, a (co) polymer of monomers having two or more ethylenically unsaturated groups is preferable.

(Polymer having a saturated hydrocarbon chain as the main chain)
Examples of the monomer having two or more ethylenically unsaturated groups include esters of polyhydric alcohol and (meth) acrylic acid {for example, ethylene glycol di (meth) acrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetra ( (Meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth)
Acrylate, trimethylolethane tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,2,3-cyclohexanetrimethacrylate, polyurethane poly Acrylate, polyester polyacrylate, etc.}, vinylbenzene and derivatives thereof (eg, 1,4-divinylbenzene, 4-vinylbenzoic acid-2-acryloylethyl ester, 1,4-divinylcyclohexanone, etc.), vinyl sulfones (eg, divinyl sulfone) ), Acrylamide (eg methylenebisacrylamide) and methacrylamide. Two or more of these monomers may be used in combination.
In the present specification, “(meth) acrylate” represents “acrylate or methacrylate”.

  In order to make the formed film have a high refractive index, the monomer structure contains an aromatic ring, at least one atom selected from halogen atoms other than fluorine, sulfur atoms, phosphorus atoms, and nitrogen atoms. It is preferable.

  Specific examples of the high refractive index monomer include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like. Two or more of these monomers may be used in combination.

(Polymerization initiator)
Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photoradical polymerization initiator or a thermal radical polymerization initiator.

(Photo radical polymerization initiator)
Photo radical polymerization initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides, 2,3-dialkyldione compounds, disulfide compounds And 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 benzophenones include benzophenone, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone. Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

  In addition, P. of “Latest UV Curing Technology”. Various examples are also described in 159 {Issuer: Kazuhiro Takasato, Issuer; Technical Information Association, Inc., published in 1991}, which is useful for the present invention.

Preferable examples of commercially available photocleavable photoradical polymerization initiators include “Irgacure (651, 184, 907)” manufactured by Ciba Specialty Chemicals.

  It is preferable to use a photoinitiator in the range of 0.1-15 mass parts with respect to 100 mass parts of polyfunctional monomers, 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.

(Thermal radical polymerization initiator)
As the thermal radical polymerization initiator, 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, peroxide Ammonium sulfate, potassium persulfate, etc .; 2-azobisisobutyronitrile, 2-azobispropionitrile, 2-azobiscyclohexanedinitrile, etc. as azo compounds, diazoaminobenzene, p-nitrobenzenediazonium, etc. as diazo compounds be able to.

(Polymer having polyether as main chain)
In the present invention, a polymer having a polyether as a main chain can also be used. A ring-opening polymer of a polyfunctional epoxy compound is preferred. The ring-opening polymerization of the polyfunctional epoxy compound can be performed by irradiation with ionizing radiation or heating in the presence of a photoacid generator or a thermal acid generator.

  Instead of or in addition to a monomer having two or more ethylenically unsaturated groups, a monomer having a crosslinkable functional group is used to introduce a crosslinkable functional group into the polymer, and this crosslinkable functional group reacts. A crosslinked structure may be introduced into the binder polymer.

  Examples of the crosslinkable functional group include an isocyanate group, an epoxy group, an aziridine group, an oxazoline group, an aldehyde group, a carbonyl group, a hydrazine group, a carboxyl group, a methylol group, and an active methylene group. Vinylsulfonic acid, acid anhydride, cyanoacrylate derivative, melamine, etherified methylol, ester and urethane, and metal alkoxide such as tetramethoxysilane can also be used as a monomer for introducing a crosslinked structure. A functional group that exhibits crosslinkability as a result of the decomposition reaction, such as a block isocyanate group, may be used. That is, in the present invention, the crosslinkable functional group may not react immediately but may exhibit reactivity as a result of decomposition.

  These binder polymers having a crosslinkable functional group can form a crosslinked structure by heating after coating.

[Hard coat layer]
The antireflection film of the present invention is preferably provided with a hard coat layer. The hard coat layer can also serve as an antiglare layer by adding matte particles for imparting antiglare properties to the binder. Moreover, it can serve as a high refractive index layer by adding an inorganic filler for increasing the refractive index, preventing crosslinking shrinkage, and increasing the strength. Further, it may be formed by adding an organosilane compound in the low refractive index layer.

(Matte particles)
In the hard coat layer, for the purpose of imparting antiglare properties, mat particles having an average particle size of 0.1 to 5.0 μm, preferably 1.5 to 3.5 μm, such as inorganic compound particles or larger than filler particles. Resin particles can be contained.

  If the difference in refractive index between the matte particles and the binder is too large, the film becomes cloudy, and if it is too small, a sufficient light diffusion effect cannot be obtained, so 0.02 to 0.20 is preferable, and 0.04 to Particularly preferred is 0.10. Similarly to the refractive index, the amount of addition of the matting particles to the binder is too large, the film becomes cloudy, and if it is too small, a sufficient light diffusion effect cannot be obtained. % Is particularly preferred.

As specific examples of the mat particles, inorganic particles such as silica particles and TiO ₂ particles; resin particles such as acrylic particles, crosslinked acrylic particles, polystyrene particles, crosslinked styrene particles, melamine resin particles, and benzoguanamine resin particles are preferable. Can be mentioned. Of these, crosslinked styrene particles, crosslinked acrylic particles, and silica particles are preferred.
As the shape of the mat particle, either a true sphere or an indefinite shape can be used.

Two or more different kinds of mat particles may be used in combination.
When two or more kinds of mat particles are used, the difference in refractive index is preferably 0.02 or more and 0.10 or less in order to effectively exert the refractive index control by mixing the two, and 0.03 or more. Is particularly preferably 0.07 or less. Further, it is possible to impart an antiglare property with mat particles having a larger particle size and to impart another optical characteristic with mat particles having a smaller particle size. For example, when an antireflection film is attached to a high-definition display of 133 ppi or higher, it is required that there is no problem in optical performance called glare. Glare originates from the fact that the pixels are enlarged or reduced due to unevenness existing on the film surface (contributing to anti-glare properties) and lose uniformity of brightness, but with a particle size smaller than that of mat particles that provide anti-glare properties. It can be greatly improved by using mat particles having a different refractive index from the binder.

  Further, the particle size distribution of the mat particles is most preferably monodisperse, and the particle sizes of the particles are preferably closer to each other. For example, when a particle having a particle size of 20% or more than the average particle size is defined as a coarse particle, the proportion of the coarse particle is preferably 1% or less, more preferably 0.1% of the total number of particles. Or less, more preferably 0.01% or less. Matt particles having such a particle size distribution are obtained by classification after a normal synthesis reaction, and a matting agent having a more preferable distribution can be obtained by increasing the number of classifications or increasing the degree of classification.

The mat particles are contained in the hard coat layer so that the amount of the mat particles in the formed hard coat layer is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² .

  The particle size distribution of the matte particles is measured by a Coulter counter method, and the measured distribution is converted into a particle number distribution.

(Inorganic filler)
The hard coat layer has at least one selected from titanium, zirconium, aluminum, indium, zinc, tin, and antimony, in addition to the above mat particles, in order to increase the refractive index of the layer and to reduce curing shrinkage. It is preferable to contain an inorganic filler made of one kind of metal oxide and having an average particle size of 0.2 μm or less, preferably 0.1 μm or less, more preferably 0.06 μm or less.

In order to increase the difference in refractive index from the mat particles, it is also preferable to use a silicon oxide in the hard coat layer using the high refractive index mat particles in order to keep the refractive index of the layer low. The preferred particle size is the same as that of the inorganic filler.

Specific examples of the inorganic filler used in the hard coat layer include TiO ₂ , ZrO ₂ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , Sb ₂ O ₃ , ITO, SiO _{2 and the} like. TiO ₂ and ZrO ₂ are particularly preferable in terms of increasing the refractive index.

  The surface of the inorganic filler is also preferably subjected to silane coupling treatment or titanium coupling treatment, and a surface treatment agent having a functional group capable of reacting with the binder species on the filler surface is preferably used.

  The amount of these inorganic fillers added is preferably 10 to 90% of the total mass of the hard coat layer, more preferably 20 to 80%, and particularly preferably 30 to 70%.

  Such a filler does not scatter because the particle size is sufficiently smaller than the wavelength of light, and a dispersion in which the filler is dispersed in a binder polymer behaves as an optically uniform substance.

  The bulk refractive index of the mixture of binder and inorganic filler in the hard coat layer in the present invention is preferably 1.48 to 2.00, more preferably 1.50 to 1.80. In order to make the refractive index within the above range, the kind and amount ratio of the binder and the inorganic filler may be appropriately selected. How to select can be easily known experimentally in advance.

  The antireflection film of the present invention thus formed has a haze value of 3 to 70%, preferably 4 to 60%, and an average reflectance of 450 nm to 650 nm is preferably 3.0% or less, preferably Is 2.5% or less. When the antireflection film of the present invention has a haze value and an average reflectance within this range, good antiglare properties and antireflection properties can be obtained without causing deterioration of the transmitted image.

[Support]
As the transparent support of the antireflection film of the present invention, a plastic film is preferably used. As a polymer for forming a plastic film, cellulose ester {for example, triacetylcellulose, diacetylcellulose, typically “TAC-TD80U”, “TAC-TD80UF”, etc., manufactured by Fuji Photo Film Co., Ltd.}, polyamide, polycarbonate, Polyester (for example, polyethylene terephthalate, polyethylene naphthalate, etc.), polystyrene, polyolefin, norbornene resin {“Arton” (trade name), manufactured by JSR Corporation}, amorphous polyolefin {“ZEONEX” (trade name), Japan ZEON Co., Ltd.}. Of these, triacetyl cellulose, polyethylene terephthalate, and polyethylene naphthalate are preferable, and triacetyl cellulose is particularly preferable.

  In addition, a cellulose acylate film substantially free of halogenated hydrocarbons such as dichloromethane and a method for producing the same are disclosed in JIII Journal of Technical Disclosure No. 2001-1745, published on March 15, 2001, the following. The cellulose acylate described here is also preferably used in the present invention.

[Saponification]
When the antireflection film of the present invention is used in an image display device, it is disposed on the outermost surface of the display by providing an adhesive layer on one side. When the transparent support of the antireflection film is triacetylcellulose, since triacetylcellulose is used as a protective film for protecting the polarizing film of the polarizing plate, it is costly to use the antireflection film of the present invention as it is for the protective film. Preferred above.

  The antireflective film of the present invention is a transparent support in order to sufficiently adhere it when it is disposed on the outermost surface of a display by providing an adhesive layer on one side or used as it is as a protective film for a polarizing plate. It is preferable to carry out a saponification treatment after an outermost layer mainly composed of a fluoropolymer is formed thereon.

  The saponification treatment is performed by a known method, for example, by immersing the film in an alkali solution for an appropriate time. After being immersed in the alkali solution, it is preferable to sufficiently wash with water so that the alkali component does not remain in the film, and to soak in a dilute acid to neutralize the alkali component. By saponification treatment, the surface of the transparent support opposite to the side having the outermost layer is hydrophilized.

  The hydrophilized surface is particularly effective for improving the adhesion with a polarizing film containing polyvinyl alcohol as a main component. In addition, the hydrophilic surface makes it difficult for dust in the air to adhere to it, so when adhering to the polarizing film, it is difficult for dust to enter between the polarizing film and the antireflective film, thus preventing point defects due to dust. It is effective for.

  The saponification treatment is preferably carried out so that the contact angle of water on the surface of the transparent support on the side opposite to the side having the outermost layer is 40 ° or less. More preferably, it is 30 ° or less, particularly preferably 20 ° or less.

  Specific means for the alkali saponification treatment can be selected from the following two means (1) and (2). (1) is superior in that it can be processed in the same process as a general-purpose triacetyl cellulose film, but since the surface of the antireflection layer is saponified, the surface is alkali-hydrolyzed and the film deteriorates. The problem that the treatment liquid becomes dirty can be a problem. In that case, although it becomes a special process, (2) is excellent.

(1) After the antireflection layer is formed on the transparent support, the back surface of the film is saponified by immersing it in an alkaline solution at least once.
(2) Before or after forming the antireflection layer on the transparent support, an alkaline solution is applied to the surface of the antireflection film opposite to the surface on which the antireflection layer is formed, and is heated, washed and / or neutralized. By doing so, only the back surface of the film is saponified.

[Coating film forming method]
The antireflection film of the present invention can be formed by the following method, but is not limited to this method.

[Application method]
First, a coating solution containing components for forming each layer is prepared. Using the obtained coating solution, dip coating method, air knife coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method, extrusion coating method (see US Pat. No. 2,681,294) Apply on a transparent support, heat and dry.

  Of these coating methods, the gravure coating method is preferable because a coating solution with a small coating amount can be applied with high film thickness uniformity as in the case of forming each layer of the antireflection film. Among the gravure coating methods, the micro gravure method is more preferable because of high film thickness uniformity.

Even with the die coating method, it is possible to apply a coating solution with a small coating amount with high film thickness uniformity, and the die coating method is a pre-weighing method, so that the film thickness can be controlled relatively easily. This is preferable because of less transpiration of the solvent.

  In the antireflection film consisting of a plurality of layers, two or more layers may be applied simultaneously. Regarding the method of simultaneous application, U.S. Pat. Nos. 2,761,791, 2,941,898, 3,508,947, 3,526,528 and Yuji Harasaki Author, “Coating Engineering”, page 253, {Asakura Shoten (1973)}.

<Use of antireflection film>
〔Polarizer〕
The polarizing plate is mainly composed of two protective films that sandwich the polarizing film from both sides. The antireflection film of the present invention is preferably used for at least one of the two protective films sandwiching the polarizing film from both sides. Since the antireflection film of the present invention also serves as a protective film, the production cost of the polarizing plate can be reduced. Further, by using the antireflection film of the present invention as the outermost layer, reflection of external light and the like can be prevented, and a polarizing plate excellent in scratch resistance, and more preferably in antifouling property can be obtained.

[Polarizing film]
As the polarizing film, a known polarizing film or a polarizing film cut out from a long polarizing film whose absorption axis is neither parallel nor perpendicular to the longitudinal direction may be used.

  A long polarizing film in which the absorption axis of the polarizing film is neither parallel nor perpendicular to the longitudinal direction is produced by the following method. That is, both ends of a continuously supplied polymer film are stretched by applying a tension while being held by a holding means and stretched at least 1.1 to 20.0 times in the film width direction. The longitudinal movement speed difference of the holding device is within 3%, and the angle formed by the film traveling direction at the exit of the step of holding both ends of the film and the substantial stretching direction of the film is inclined by 20 to 70 °. It can be produced by a stretching method in which the traveling direction is bent with both ends of the film held. In particular, those inclined at 45 ° are preferably used from the viewpoint of productivity.

  The method for stretching the polymer film is described in detail in paragraphs 0020 to 0030 of JP-A-2002-86554.

(Image display device)
The antireflection film of the present invention and the polarizing plate using the antireflection film as at least one side of the surface protective film of the polarizing film can be used as an image display device by being used on the outermost surface of the display. Twisted Nematic (TN), Super Twisted Nematic (STN), Vertical Alignment (VA), In-Plane Switching (IPS), Optically Compensated Bend Cell (OCB) mode transmission type, reflective type, or semi It can be preferably used for a transmissive liquid crystal display device.

In VA mode liquid crystal cell,
(1) In addition to a narrowly-defined VA mode liquid crystal cell (described in JP-A-2-176625) in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied. ,
(2) Liquid crystal cell ("SID97, Digest of tech. Papers" (Preliminary Collection), Vol. 28 (1997), p. 845},
(3) A liquid crystal cell of a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied {"Preliminary Collection of Japan Liquid Crystal Society" p. 58-59 (1998) description}, and
(4) Includes SURVAVAL mode liquid crystal cells (announced at "LCD International 98").

  For a VA mode liquid crystal cell, a polarizing plate prepared by combining a biaxially stretched triacetyl cellulose film with the antireflection film of the present invention is preferably used. As for the method for producing a biaxially stretched triacetyl cellulose film, for example, the methods described in JP-A Nos. 2001-249223 and 2003-170492 are preferably used.

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

  In an ECB mode liquid crystal cell, rod-like liquid crystal molecules are substantially horizontally aligned when no voltage is applied, and is most frequently used as a color TFT liquid crystal display device, and is described in many documents. For example, it is described in “EL, PDP, LCD display” {issued by Toray Research Center (2001)}.

  In particular, for a TN mode or IPS mode liquid crystal display device, as described in Japanese Patent Application Laid-Open No. 2001-100043, an optical compensation film having an effect of widening the viewing angle is protected on the two sides of the polarizing film. By using it on the surface of the film opposite to the antireflection film of the present invention, a polarizing plate having an antireflection effect and a viewing angle expansion effect can be obtained with the thickness of one polarizing plate, which is particularly preferable.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto. In the following Examples and Synthesis Examples,% represents mass% unless otherwise specified.

<Curable composition>
[Synthesis of fluoropolymer]
Synthesis Example 1: Synthesis of fluorinated polymer (P2) In an autoclave with a stainless steel stirrer having an internal volume of 100 mL, 18.5 g of ethyl acetate, 8.8 g of hydroxyethyl vinyl ether (HEVE), “Silaplane FM-0725” {Chisso ( Co., Ltd.} 1.0 g and “V-65” {thermal radical generator, Wako Pure Chemical Industries, Ltd.} 0.40 g were charged, the system was deaerated and replaced with nitrogen gas. Further, 15 g of hexafluoropropylene (HFP) was introduced into the autoclave and heated to 62 ° C. The pressure when the temperature in the autoclave reached 62 ° C. was 8.9 kg / cm ² . The reaction was continued for 9 hours while maintaining the inside of the autoclave at 62 ° C., and when the pressure reached 6.2 kg / cm ² , the heating was stopped and the mixture was allowed to cool.

When the internal temperature dropped to room temperature, unreacted monomers were driven out, the autoclave was opened, and the reaction solution was taken out. The obtained reaction liquid was put into a mixture of a large excess of hexane and 2-propanol, and the precipitated polymer was taken out by removing the solvent by decantation. Further, this polymer was dissolved in a small amount of ethyl acetate and reprecipitated twice from a mixture of hexane and 2-propanol to completely remove the remaining monomer and dried under reduced pressure to obtain 8 fluorine-containing polymer (P2). .3 g was obtained. The number average molecular weight of the obtained polymer was 17,000.

Synthesis Example 2: Synthesis of fluorinated polymer (P3) 30 g of ethyl acetate, 8.8 g of hydroxyethyl vinyl ether (HEVE), “VPS-1001” {macroazo initiator: Wako Jun Yakuhin Co., Ltd.} 0.88 g and lauroyl peroxide 0.29 g were charged, the system was degassed and replaced with nitrogen gas. Further, 15 g of hexafluoropropylene (HFP) was introduced into the autoclave and heated to 70 ° C. The pressure when the temperature in the autoclave reached 70 ° C. was 9.0 kg / cm ² . The reaction was continued for 9 hours while maintaining the inside of the autoclave at 70 ° C. When the pressure reached 6.0 kg / cm ² , the heating was stopped and the mixture was allowed to cool.

  When the internal temperature dropped to room temperature, unreacted monomers were driven out, the autoclave was opened, and the reaction solution was taken out. The obtained reaction liquid was put into a mixture of a large excess of hexane and 2-propanol, and the precipitated polymer was taken out by removing the solvent by decantation. Further, this polymer was dissolved in a small amount of ethyl acetate and reprecipitated twice from a mixture of hexane and 2-propanol to completely remove the residual monomer, and dried under reduced pressure to obtain 19 fluorine-containing polymer (P3). .3 g was obtained. The number average molecular weight of the obtained polymer was 21,000.

Synthesis Examples 3-9
In substantially the same manner as in Synthesis Example 1, fluoropolymers (P1), (P6), (P8), (P9), (P19), (P23), and (P25) were synthesized. The number average molecular weight of each of the obtained fluoropolymers is as shown in Tables 1 and 2 above.

Comparative Synthesis Example 1
A fluoropolymer (PR-1) was synthesized in the same manner as the polymer of Synthesis Example 3 in the examples of JP-A-2001-89623. In this polymer, the content of polymerization units derived from HEVE, which is a hydroxyl group-containing monomer, is about 15 mol%.

(Preparation of curable composition)
Examples 1-1 to 1-30 and Comparative Examples 1-1 to 1-4
[Preparation of coating solutions for low refractive index layers (LL-1 to LL-30) and (LLR-1) to (LLR-4))
Each component shown in Table 7 was mixed and dissolved in 2-butanone to prepare a coating solution for a low refractive index layer having a solid content of 6%. The values in parentheses in Table 7 represent parts by mass of the solid content of each component.

Abbreviations in Table 7 are as follows.
CY303: “Cymel 303”, methylolated melamine, manufactured by Nippon Cytec Industries, Ltd.
MX270: “Nicalak MX-270”, tetramethoxymethylglycoluril, manufactured by Sanwa Chemical Co., Ltd.
DEX314: “DEX-314”, epoxy-based curing agent, manufactured by Nagase Chemical Industries, Ltd.
FM4425: “FM-4425”, a compound having a polysiloxane structure, manufactured by Chisso Corporation
CMS626: “CMS-626”, a compound having a polysiloxane structure, manufactured by Gelest,
160AS: “X-22-160AS”, a compound having a polysiloxane structure, manufactured by Shin-Etsu Chemical Co., Ltd.
Colloidal silica: “MEK-ST” manufactured by Nissan Chemical Industries, Ltd.
And H-11 and H-21 each represent a compound having the following structure.

In addition, about the following acid catalyst and thermal acid generator, it described in the column of the photosensitive acid generator for convenience.
PTS: p-toluenesulfonic acid monohydrate CAT4050: catalyst 4050 (thermal acid generator, manufactured by Mitsui Cytec)

<Preparation of antireflection film>
Example 2-1
[Preparation of coating liquid for hard coat layer (HC-1)]
"PET-30" 50.0g
"Irgacure 184" 2.0g
"SX-350" (30%) 1.5g
Cross-linked acrylic-styrene particles (30%) 13.9g
"KBM-5103" 10.0g
Toluene 38.5g

  The mixed solution was filtered through a polypropylene filter having a pore size of 30 μm to prepare a hard coat layer coating solution (HC-1).

The compounds used are shown below.
“PET-30”: a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate {manufactured by Nippon Kayaku Co., Ltd.}
“Irgacure 184”: Polymerization initiator {Ciba Specialty Chemicals Co., Ltd.}
“SX-350”: Cross-linked polystyrene particles having an average particle size of 3.5 μm {refractive index 1.60, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion. Use after dispersion for 20 minutes at 10,000 rpm in a Polytron disperser}.
Cross-linked acrylic-styrene particles: average particle size 3.5 μm {refractive index 1.55, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion. Use after dispersion for 20 minutes at 10,000 rpm in a Polytron disperser}.
“KBM-5103”: acryloyloxypropyltrimethoxysilane {manufactured by Shin-Etsu Chemical Co., Ltd.}.

[Preparation of antireflection film (101)]
An 80 μm-thick triacetyl cellulose film “TAC-TD80U” {manufactured by Fuji Photo Film Co., Ltd.} is unwound in a roll form, and the hard coat layer coating solution (HC-1) is directly Using a micro gravure roll with a diameter of 50 mm having a gravure pattern of 180 lines / in and a depth of 40 μm, and a doctor blade, it was applied under the conditions of a gravure roll rotation speed of 30 rpm and a conveyance speed of 30 m / min, and dried at 60 ° C. for 150 seconds. Further, using an “air-cooled metal halide lamp” {manufactured by Eye Graphics Co., Ltd.) with an oxygen concentration of 0.1 vol% under a nitrogen purge, ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 110 mJ / cm ² are used. The coating layer was cured by irradiation to form a 6 μm thick layer and wound up. The surface roughness of the hard coat layer thus obtained was Ra = 0.18 μm, Rz = 1.40 μm, and haze 35%.

On the hard coat layer thus obtained, the above-described coating solution for low refractive index layer (LL-1) is used, and the thickness of the low refractive index layer is adjusted to 95 nm, so that an antireflection film sample is obtained. (101) was produced. Ultraviolet curing conditions for the low refractive index layer were as follows: a 240 W / cm “air-cooled metal halide lamp” {manufactured by Eye Graphics Co., Ltd.) with nitrogen purge, an illuminance of 120 mW / cm ² and an irradiation amount of 240 mJ / cm ² . It was set as the irradiation amount, and it heated at 80 degreeC after that for 2 minutes.

Examples 2-2 to 2-30 and comparative examples 2-1 to 2-4
[Preparation of antireflection films (102) to (130) and (R01) to (R04)]
In the production of the antireflection film (101), an antireflection film (101) was used except that any one of (LL-2) to (LL-30) was used instead of using the coating solution for low refractive index layer (LL-1). ), Antireflection films (102) to (130) were produced. Further, instead of using the coating solution for low refractive index layer (LL-1), except that any of (LLR-1) to (LLR-4) is used, it is the same as the production of the antireflection film (101), Comparative antireflection films (R01) to (R04) were produced.

[Saponification treatment of antireflection film]
The obtained antireflection film was treated and dried under the following saponification standard conditions.
Alkaline bath: 1.5 mol / dm ³ sodium hydroxide aqueous solution, 55 ° C.-120 seconds.
First washing bath: tap water, 60 seconds.
Neutralization bath: 0.05 mol / dm ³ sulfuric acid, 30 ° C.-20 seconds.
Second washing bath: tap water, 60 seconds.
Drying: 120 ° C., 60 seconds.

[Evaluation of antireflection film]
The following evaluation was performed using the saponified antireflection film thus obtained. The evaluation results are shown in Table 8 together with the constitution of each antireflection film layer.

(Evaluation 1) Measurement of average reflectance Using a spectrophotometer “V-550” {manufactured by JASCO Corp.}, spectral reflectance at an incident angle of 5 ° using an integrating sphere in a wavelength region of 380 to 780 nm. Was measured. In the evaluation of the spectral reflectance, an average reflectance of 450 to 650 nm was used.
After the back surface of the antireflection film was roughened, it was light-absorbed with black ink (transmittance at 380 to 780 nm was less than 10%) and measured on a black table.

  In addition, the sample processed into the polarizing plate mentioned later measured using the thing of a polarizing plate form as it is. In the case of a display device that does not use a polarizing plate, the back surface of the antireflection film is roughened and then light-absorbed with black ink (transmittance at 380 to 780 nm is less than 10%). Measured on a table.

(Evaluation 2) Eraser rubbing scratch resistance evaluation A rubbing test was conducted using a rubbing tester under the following conditions.
Evaluation environmental conditions: 25 ° C., 60% RH.
Rubbing material: A plastic eraser {"MONO" manufactured by Dragonfly Pencil Co., Ltd.) was fixed to the rubbing tip (1 cm x 1 cm) of the tester that was in contact with the sample.
Travel distance (one way): 4cm
Rubbing speed: 2 cm / second,
Load: 500 g / cm ² ,
Tip contact area: 1 cm × 1 cm.
Number of rubbing: 100 reciprocations.

Oily black ink was applied to the back side of the rubbed sample and visually observed with reflected light, and scratches on the rubbed portion were evaluated according to the following criteria.
○: Even if you look very carefully, no scratches are visible.
○ △: Slightly weak scratches are visible when viewed very carefully.
Δ: Weak scratches are visible.
Δ ×: moderate scratches are visible.
X: There is a scratch that can be seen at first glance.
XX: Single-sided film is damaged.

(Evaluation 3) “Magic Ink” Adhesion Evaluation As an index of surface contamination resistance, the antireflection film was conditioned at a temperature of 25 ° C. and 60% RH for 2 hours, and then “Magic ink” was adhered to the sample surface. Then, the state when the substrate was wiped off with a cleaning cloth was observed, and the magic adhesion was evaluated as follows.
A: The traces of magic can be completely wiped off.
○: A trace of magic is visible.
Δ: A little trace of magic is visible.
X: The trace of magic can hardly be wiped off.

(Evaluation 4) Coating solution stability evaluation The coating solution prepared in Example 1 was sealed at 30 ° C. and 60% RH and stored for 1 month, and then an antireflection film was prepared in the same manner as in Example 1. . An oil-based black ink was applied to the back side of the sample and visually observed with reflected light, and the surface condition was evaluated according to the following criteria.
○: Even if looked very carefully, unevenness is not visible.
○ △: Slightly weak unevenness is seen when viewed very carefully.
Δ: Weak unevenness is visible.
Δ ×: Medium unevenness is visible.
×: Unevenness that can be seen at first glance.

  The evaluation results are shown in Table 8. The sample prepared in Evaluation 4 is different from the samples used in Evaluations 1 to 3, but is listed in Table 8 because it uses the same component coating solution.

  As is clear from this example, the antireflection film samples (101) to (130) of Examples 2-1 to 2-30 of the present invention have excellent scratch resistance and antifouling properties. I understand that. In the antireflection film sample (R01) of Comparative Example 2-1 using sulfonic acid as the curing catalyst, the curing reaction partially progressed in the coating solution, and the surface condition deteriorated. The antireflective film sample (R02) of Comparative Example 2-2 using a thermal acid generator as a curing catalyst is not sufficiently cured by low-temperature and short-time curing treatment, resulting in insufficient scratch resistance and contamination resistance. Could not be evaluated. Further, in the antireflection film samples (R03) and (R04) of Comparative Examples 2-3 and 2-4 using the comparative polymer (PR-1) having a low OH group content as the fluoropolymer, a cured film formed Since the hardness of the film became low, the scratch resistance was insufficient and the contamination resistance could not be evaluated in part.

  From the above results, by satisfying the requirements of the present invention, it is possible to provide a curable composition capable of producing a film excellent in scratch resistance and stain resistance under mild conditions, and further, to provide a high-quality antireflection film. It is clear to give.

Example 3-1
The multilayer antireflection film shown below was produced.

[Preparation of coating liquid for hard coat layer (HC-2)]
"Desolite Z7404" {Hardcoat composition liquid containing zirconia fine particles: manufactured by JSR Corporation} 100 parts by mass, "DPHA" {UV curable resin: manufactured by Nippon Kayaku Co., Ltd.} 31 parts by mass, "KBM-5103" { Silane coupling agent: manufactured by Shin-Etsu Chemical Co., Ltd.} 10 parts by mass, 29 parts by mass of methyl ethyl ketone (MEK), 13 parts by mass of methyl isobutyl ketone (MIBK), 5 parts by mass of cyclohexanone are stirred into a mixing tank and hard coated. A layer coating solution (HC-2) was obtained.

[Preparation of Antireflection Film (201)]
As a support, a triacetyl cellulose film “TAC-TD80U” (manufactured by Fuji Photo Film Co., Ltd.) was unwound in a roll form, and the above-mentioned coating liquid for hard coat layer (HC-2) was obtained with 135 wires / Using a micro gravure roll with a diameter of 50 mm having a gravure pattern with an inch and a depth of 60 μm, and a doctor blade, coating was performed at a conveyance speed of 10 m / min, drying at 60 ° C. for 150 seconds, and further 160 W / cm under a nitrogen purge. Using an “air-cooled metal halide lamp” {manufactured by Eye Graphics Co., Ltd.}, irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 100 mJ / cm ² to cure the coating layer to form a hard coat layer, Winded up. The hard coat layer was formed by adjusting the rotation speed of the gravure roll so that the thickness of the hard coat layer after curing was 4.0 μm.

On the hard coat layer thus obtained, the above-described coating solution for low refractive index layer (LL-1) is used, and the thickness of the low refractive index layer is adjusted to 95 nm, so that an antireflection film sample is obtained. (201) was produced. Ultraviolet curing conditions for the low refractive index layer were as follows: a 240 W / cm “air-cooled metal halide lamp” {manufactured by Eye Graphics Co., Ltd.) with nitrogen purge, an illuminance of 120 mW / cm ² and an irradiation amount of 240 mJ / cm ² . It was set as the irradiation amount, and then heated at 80 ° C. for 2 minutes.

Examples 3-2 to 3-30
[Preparation of antireflection films (202) to (230)]
In producing the antireflection film (201), instead of using the coating solution for low refractive index layer (LL-1), an antireflection film (201) except that any one of (LL-2) to (LL-30) is used. The antireflection films (202) to (230) were produced in the same manner as in the production of).

  When the antireflection films (201) to (230) were evaluated according to Example 2, the same effect was obtained by using the low refractive index layer of the present invention.

<Use of antireflection film>
[Production of polarizing plate with antireflection film]
Example 4
A polarizing film was prepared by adsorbing iodine to a stretched polyvinyl alcohol film. Next, the saponified antireflective film prepared in Example 2 was used on one side of the polarizing film using a polyvinyl alcohol-based adhesive so that the support (triacetylcellulose) side of the antireflective film was the polarizing film side. Pasted on. A viewing angle widening film “Wide View Film SA12B” (manufactured by Fuji Photo Film Co., Ltd.) having an optical compensation layer was saponified and attached to the other side of the polarizing film using a polyvinyl alcohol adhesive. In this way, a polarizing plate was produced. As a result of performing the evaluation according to Example 2 in this polarizing plate state, the same effect was obtained by using the low refractive index layer of the present invention.

[Production of image display device]
Example 5
The antireflection film samples of Examples 2 and 3 and the polarizing plate sample of Example 4 using the antireflection film of Example 2 were bonded to the glass plate on the surface of the organic EL display device through an adhesive, respectively. As a result, in all cases, reflection on the glass surface was suppressed, and a display device with high visibility was obtained.

Fig.1 (a) is a cross-sectional schematic diagram which shows the layer structure of one Embodiment in the antireflection film of this invention. FIG.1 (b) is a cross-sectional schematic diagram which shows the layer structure of another embodiment in the antireflection film of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a: Antireflection film 1b: Antireflection film 2: Transparent support 3: Hard coat layer 4: Anti-glare hard coat layer 5: Low refractive index layer 7: Medium refractive index layer 8: High refractive index layer

Claims (10)

The following components (A), (B) and (C):
(A) a fluorine-containing polymer containing at least one fluorine-containing vinyl monomer polymerization unit (a) and a hydroxyl group-containing vinyl monomer polymerization unit (b), and the proportion of the polymerization unit (b) exceeding 20 mol% At least one,
(B) at least one crosslinking agent capable of reacting with a hydroxyl group, and (C) at least one compound that generates an acid upon irradiation with ionizing radiation,
A curable composition comprising: The fluorine-containing polymer (A) further contains at least one polymer unit (c) having a graft site containing a polysiloxane repeating unit represented by the following general formula (1) in the side chain, and the main chain is only a carbon atom. The curable composition according to claim 1.
General formula (1):

In formula (1), R ¹¹ and R ¹² may be the same or different and each represents an alkyl group or an aryl group. p represents an integer of 5 to 500. The curable composition according to claim 1, wherein the fluorine-containing polymer (A) further contains a polysiloxane repeating unit (d) represented by the following general formula (1) in the main chain.
General formula (1):

In formula (1), R ¹¹ and R ¹² may be the same or different and each represents an alkyl group or an aryl group. p represents an integer of 5 to 500.   The composition further comprises a compound having a polysiloxane structure containing a hydroxyl group, a functional group capable of reacting with a hydroxyl group to form a bond, or a functional group capable of reacting with the crosslinking agent to form a bond. The curable composition in any one of -3.   The curability according to any one of claims 1 to 4, wherein the crosslinking agent is a compound containing a nitrogen atom in the molecule and containing two or more carbon atoms substituted with an alkoxy group adjacent to the nitrogen atom. Composition.   Hardened | cured material formed by hardening | curing the curable composition in any one of Claims 1-5.   The film which has a layer formed by coating the curable composition in any one of Claims 1-5 on a transparent support body.   An antireflection film having a low refractive index layer formed by coating the curable composition according to any one of claims 1 to 5 on a transparent support.   The antireflection film according to claim 8 is used for one of two protective films of a polarizing film in a polarizing plate.   An anti-reflection film according to claim 8 or a polarizing plate according to claim 9 is used on the outermost surface of a display.

Images