JP2009198863A - Antireflection film and image display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antireflection film which has high antistatic characteristics and high light transmissivity, is superior in surface friction resistance and surface abrasion resistance and is neutral in color, has favorable surface appearance and to provide an image display apparatus that has the antireflection film incorporated therein. <P>SOLUTION: The antireflection film 6 includes a hard coat layer 2 containing an acrylic resin and high refractive index particles and a low refractive index layer 1 containing silica system particulates successively laminated on at least one surface of a base material film 3. The low refractive index layer forming an uppermost layer of the antireflection film includes at least one of polyether modified poly(dimethyl siloxane) and polyester modified poly(dimethyl siloxane). Further the image display apparatus having the antireflection film adhered to an image display surface or a front plate surface is obtained. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an antireflection film having extremely low reflectance, good light transmittance, antistatic properties, and particularly excellent surface friction resistance, and an image display device using the same. More specifically, the present invention relates to an antireflection film used on the display display surface, the surface of the deflecting plate, and the like. The present invention also relates to an image display device incorporating an antireflection film.

  In display devices such as televisions and personal computer monitors, external light such as sunlight and fluorescent lamps is reflected and reflected on the surface, which makes it difficult to see the displayed image. In order to solve this problem, a method has been employed in which irregularities are provided on the surface to diffuse externally reflected light, or thin films having a high refractive index and a low refractive index are alternately laminated to prevent light reflection.

  However, the method of irregularly reflecting external light is insufficient in terms of improving the visibility of the image because the image on the display looks blurred.

  As a method for improving this, a method (Patent Document 1) is proposed in which a hard coat layer containing high refractive index particles and a low refractive index layer are provided on the surface of an organic film.

  However, when the antireflection film provided by this method is attached to the display surface, the display member and the antireflection film surface come into contact with each other, and a frictional sound is generated due to vibration or the like. . Furthermore, it is insufficient in that the film is easily damaged by contact between the film and the member.

Therefore, in order to reduce friction, generally, a fluorine organic compound such as perfluoroethylene is used in the layer on the film surface (Patent Document 2), alkoxysilane, and a silicone-based lubricant are added (Patent Document 3). ) Etc. have been proposed. However, although the improvement of slipperiness is recognized by this method, the frictional sound due to contact with the display member is not eliminated, and it is not sufficient that the unpleasant sound is intermittently generated.
Japanese Patent Laid-Open No. 9-226062 JP-A-11-258405 Japanese Patent Laid-Open No. 11-84103

  In view of the background art, the present invention has a very low reflectance, a good light transmittance and an antistatic property, and a good antireflection film having particularly excellent surface scratch resistance and friction resistance, and incorporating the same It is intended to provide an image display device.

  The present invention employs the following means in order to solve such problems. That is, in the antireflection film of the present invention, a hard coat layer containing an acrylic resin and high refractive index particles and a low refractive index layer containing silica fine particles are sequentially laminated on at least one surface of the base film. The antireflective film is characterized in that the low refractive index layer forming the uppermost layer of the antireflective film contains at least one of polyether-modified polydimethylsiloxane and polyester-modified polydimethylsiloxane.

  The image display device of the present invention is characterized in that the antireflection film is adhered to the image display surface or the surface of the front plate.

  According to the present invention, it is possible to provide an antireflection film having extremely low reflectance, good light transmittance, antistatic properties, and particularly excellent surface friction resistance. It is suitably used as an antireflection film applied to the front surface of flat televisions with large screens and the front surface of liquid crystal televisions.

  The present invention has the above-mentioned problem, that is, low reflectance of the surface, and the present invention has the above-mentioned problem, that is, low reflectance, good light transmittance and antistatic property, and anti-reflection with particularly excellent surface friction resistance. The film has been studied earnestly, and a low refractive index layer containing a compound comprising a specific hard coat layer and a specific polyether-modified polydimethylsiloxane compound group, etc., a hard coat layer and a low refractive index on at least one surface of the base film. As a result of laminating the layers in the order of layers, it has been found that these problems can be solved at once.

  The hard coat layer of the present invention needs to contain acrylic resin and high refractive index particles as main components in order to impart hardness, durability and reflection characteristics to the antireflection film. The term “main component” as used herein means that the mass fraction of the total amount of the acrylic resin and the high refractive index particles in 100% by mass of the hard coat layer is 50% by mass or more.

  The hard coat layer of the present invention is excellent in curability, flexibility, and productivity, and has hardness and durability at low cost. In the hard coat layer, the main component is an acrylic resin and high refractive index particles. As the acrylic resin, an actinic ray curable acrylic resin or a thermosetting acrylic resin is preferably used. Among such acrylic resins, (meth) acrylate is preferable. The system resin is easy to radically polymerize by actinic ray irradiation, and may have an effect of improving the solvent resistance and hardness of the formed film.

  More preferably, a (meth) acrylate resin having a (meth) acryloyl group composed of two or more polyfunctional (meth) acrylate compounds in the molecule may improve solvent resistance. For example, as such (meth) acrylate resin, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, ethylene-modified trimethylolpropane tri (meth) acrylate, tris- ( 2-hydroxyethyl) -isocyanuric acid ester tri (meth) acrylate such as tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. A tetrafunctional or higher functional (meth) acrylate or the like is used. In the present invention, “... (Meta) acrylic ...” is an abbreviation of “... acrylic ... or meta acrylic ...”.

  For the acrylic resin in the hard coat layer, a (meth) acrylate compound (monomer) having an acidic functional group such as a carboxyl group, a phosphoric acid group, or a sulfonic acid group is used to improve the dispersibility of the particles. be able to. Specifically, as the acidic functional group-containing monomer, unsaturated carboxylic acid such as acrylic acid, methacrylic acid, crotonic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethylphthalic acid, Phosphoric acid (meth) acrylic acid esters such as mono (2- (meth) acryloyloxyethyl) acid phosphate and diphenyl-2- (meth) acryloyloxyethyl phosphate, 2-sulfoester (meth) acrylate, and the like are used. In addition, a (meth) acrylate compound having a polar bond such as an amide bond, a urethane bond, or an ether bond can be used. Furthermore, a resin having a urethane bond, such as a urethane (meth) acrylate oligomer, is particularly preferable because of its high polarity and good particle dispersibility.

  When forming a hard-coat layer by this invention, you may use an initiator in order to advance hardening. As the initiator, the applied acrylic resin initiates or accelerates polymerization and / or crosslinking reaction by radical reaction, anion reaction, cation reaction, etc., and various conventionally known photopolymerization initiators can be used. It is.

  Specific examples of such photopolymerization initiators include sulfides such as sodium methyldithiocarbamate sulfide, diphenyl monosulfide, dibenzothiazoyl monosulfide and disulfide, thioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, Thioxanthone derivatives such as 2,4-diethylthioxanthone, azo compounds such as hydrazone and azobisisobutyronitrile, diazo compounds such as benzenediazonium salt, benzoin, benzoin methyl ether, benzoin ethyl ether, benzophenone, dimethylaminobenzophenone Michler's ketone, benzylanthraquinone, t-butylanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-aminoanthraquinone, Aromatic carbonyl compounds such as -chloroanthraquinone, dialkylaminobenzoic acid esters such as methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, butyl D-dimethylaminobenzoate, isopropyl p-diethylaminobenzoate, Peroxides such as benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, cumene hydroperoxide, 9-phenylacridine, 9-p-methoxyphenylacridine, 9-acetylaminoacridine, benzacridine, etc. Acridine derivatives, phenazine derivatives such as 9,10-dimethylbenzphenazine, 9-methylbenzphenazine, 10-methoxybenzphenazine, and 6,4 ′, 4 ″ -trimethoxy-2,3-diphenylquinoxaline Quinoxaline derivatives, 2,4,5-triphenylimidazolyl dimer, 2-nitrofluorene, 2,4,6-triphenylpyrylium tetrafluoride boron salt, 2,4,6-tris (trichloromethyl) ) -1,3,5-triazine, 3,3′-carbonylbiscoumarin, thiomichler ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, oligo (2-hydroxy-2-methyl-1- ( 4- (1-methylvinyl) phenyl) propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, and the like can be used.

  The amount of the photopolymerization initiator is preferably 0.1 to 20 parts by mass, more preferably 1.0 to 15.0 parts by mass with respect to 100 parts by mass of the acrylic resin. If it is less than 0.1 parts by mass, photopolymerization is slow, and it tends to require long-time light irradiation in order to satisfy hardness and scratch resistance, and sometimes tends to be uncured. On the other hand, when it exceeds 20 mass parts, functions, such as antistatic property of a coating film, abrasion resistance, and a weather resistance, will fall easily.

  Moreover, when forming a hard-coat layer by this invention, in order to prevent the fall of the sensitivity of the said initiator by oxygen inhibition, you may coexist an amine compound with a photoinitiator. Such an amine compound is not particularly limited as long as it is a non-volatile compound such as an aliphatic amine compound or an aromatic amine compound. For example, triethanolamine, methyldiethanolamine and the like are suitable.

  The hard coat layer of the present invention needs to contain high refractive index particles in the hard coat layer in order to increase the refractive index and enhance the antireflection performance.

Examples of the high refractive index particles include those having a refractive index of 1.6 or more and ultrafine particles of metal or metal oxide, such as zinc, titanium, aluminum, cerium, yttrium, niobium, zirconium, antimony, indium, and tin. At least one or two or more oxide particles selected from the group consisting of can be used. For example, ZnO (refractive index 1.90), TiO ₂ (refractive index 2.3 to 2.7), CeO ₂ (refractive index 1.95), SbO ₂ (refractive index 1.71), Y ₂ O ₃ ( Examples include refractive index 1.87), La ₂ O ₃ (refractive index 1.95), ZrO ₂ (refractive index 2.05), Al ₂ O ₃ (refractive index 1.63).

  Furthermore, in order to impart antistatic properties to the hard coat layer, it is possible to use conductive metal oxide particles having the advantage of high transparency as a high refractive index particle, which is less dependent on humidity and processing conditions, and has high transparency. it can.

  As the conductive metal oxide particles, one or more oxide particles selected from indium, tin, zinc, and antimony can be used. Examples thereof include tin-containing antimony oxide particles (ATO), zinc-containing antimony oxide particles, tin-containing indium oxide particles (ITO), zinc oxide / aluminum oxide particles, and antimony oxide particles.

  Such high refractive index particles have an average particle size (sphere equivalent diameter measured by the BET method shown in JIS R1626 (defined in JIS Z8819-1)), preferably 0.5 μm or less, more preferably Particles having a particle size of 0.001 to 0.3 μm, particularly preferably 0.005 to 0.2 μm are preferably used. If the average particle diameter exceeds this range, the transparency of the coating film (A layer) is reduced. If the average particle diameter is less than this range, the particles tend to aggregate and the haze value of the generated coating film (A layer) increases. In either case, it becomes difficult to obtain a desired haze value.

  The mass ratio of the high refractive index particles to 100% by mass of the acrylic resin is preferably 20% by mass to 90% by mass, and more preferably 30% by mass to 80% by mass.

  If the high refractive index particles are less than 20% by mass with respect to 100% by mass of the acrylic resin, the effect of increasing the refractive index cannot be achieved and the resulting film has a high reflectance.

  If the high refractive index particles exceed 90% by mass with respect to 100% by mass of the acrylic resin, various physical and chemical strengths of the resulting film tend to be deteriorated, and the haze value tends to be high and transparency tends to be lowered. There is not preferable. The above is preferable in order to achieve a high refractive index and reduce the reflectivity, and more preferably 60% by mass or more.

  In the present invention, the constituent component of the hard coat layer may contain a silane coupling agent for the purpose of improving the adhesion with the low refractive index layer. In particular, the hydrolyzate of the silane coupling agent is used to improve the adhesion between the hard coat layer and the low refractive index layer after changes in temperature and humidity occur.

  As the silane coupling agent, a compound having a hydrolyzable alkoxy group such as a methoxy group and an ethoxy group and a reactive functional group such as a vinyl group, an acrylic group, a methacryl group, an epoxy group, an amino group, and an isocyanate group. can give.

  Examples of silane coupling agents having these reactive functional groups include vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3- Glycidoxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxy Propyltrimethoxysilane, N-2 (aminoethyl) 3-aminopropylmethyldimethoxysilane, N-2 (aminoethyl) 3-aminopropyltrimethoxysilane, N-2 (aminoethyl) 3-aminopropyltriethoxy Silane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, Examples thereof include N- (vinylbenzyl) -2-aminoethyl-3-aminopropylsilane and 3-isocyanatopropyltriethoxysilane.

  As a hydrolyzate of a silane coupling agent, it can carry out by hydrolyzing the alkoxy group of the said silane coupling agent. A known method can be employed for the hydrolysis.

  In the present invention, for the purpose of improving surface hardness, inorganic particles such as colloidal silica, dry silica, wet silica and titanium oxide, colloidally dispersed silica fine particles, and the like are further included in the constituents of the hard coat layer. You can also.

  The hard coat layer of the present invention preferably has a thickness of 0.3 μm or more. When the thickness of the hard coat layer is less than 0.3 μm, the scratch resistance of the surface is remarkably lowered, and the difference between the maximum reflectance and the minimum reflectance in the 400 to 700 nm region becomes large, and a neutral color tone can be obtained. Since it becomes difficult, it is unsuitable, and more preferably 1 μm or more. In order to suppress curling as an antireflection film, the thickness of the hard coat layer is preferably 20 μm or less, more preferably 15 μm or less.

  The hard coat layer of the present invention preferably has a refractive index of 1.50 or more and 1.70 or less in order to realize a neutral color tone. When the refractive index of the hard coat layer is higher than 1.70, the reflectance becomes high, the reflected light in a specific wavelength region becomes relatively strong, and the function as an antireflection film is lost. Further, when the refractive index is lower than 1.50, particularly lower than the refractive index of the low refractive index layer, it does not function as an antireflection film. A refractive index of 1.50 or more is preferable from the viewpoint of suppressing an increase in the minimum reflectance.

  In addition, it is preferable that the refractive index of the hard coat layer is higher than the refractive index of the low refractive index layer because the reflectance of the antireflection film can be reduced.

  The low refractive index layer of the present invention is a layer having a refractive index smaller than that of the base film and the hard coat layer, and preferably has a refractive index of 1.30 to 1.50, more preferably 1.30 to 1.40. This is preferable for improving the antireflection effect.

  Examples of the material for forming the low refractive index layer include silicon alkoxides, ultraviolet curable acrylic resins, and reactive organic silicon compounds.

  The silicon alkoxide system is a compound represented by RmSi (OR ') n, wherein R and R' represent an alkyl group having 1 to 10 carbon atoms, m + n is 4, and m and n are each an integer. Specifically, tetramethoxysilane, tetraethoxysilane, tetra-iso-propoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane Tetrapentaethoxysilane, tetrapenta-n-propoxysilane, tetrapenta-iso-propoxysilane, tetrapenta-n-butoxysilane, tetrapenta-sec-butoxysilane, tetrapenta-tert-butoxysilane, methyltrimethoxysilane, methyltrimethoxysilane Ethoxysilane, methyltripropoxysilane, methyltributoxysilane, dimethyltridimethoxysilane, dimethyltridiethoxysilane, dimethylmethoxysilane, dimethylethoxysilane, dimethylpro Kishishiran, dimethyl-butoxy silane, methyl dimethoxy silane, methyl diethoxy silane and the like.

  A known method can be employed for the hydrolysis of the silicon alkoxide compound. As the hydrolysis catalyst, an acidic catalyst such as an organic acid or an inorganic acid is preferable because the time required for the production process can be shortened. Although it does not specifically limit as an acidic catalyst, Acid catalysts, such as a formic acid, oxalic acid, hydrochloric acid, a sulfuric acid, an acetic acid, trifluoroacetic acid, phosphoric acid, polyphosphoric acid, polyhydric carboxylic acid or its anhydride, an ion exchange resin, are mentioned.

  A preferable addition amount of the acidic catalyst is preferably 0.05% by weight to 10% by weight, particularly preferably 0.1% by weight to 5% by weight, with respect to the silicon alkoxide compound. If the amount of the acid catalyst is less than 0.05% by weight, the hydrolysis reaction may not proceed sufficiently. If it exceeds 10% by weight, the hydrolysis reaction may run away.

  The solvent used for the hydrolysis reaction is preferably an organic solvent, alcohols such as ethanol, propanol, butanol and 3-methyl-3-methoxy-1-butanol; glycols such as ethylene glycol and propylene glycol; ethylene glycol monomethyl Ethers such as ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether and diethyl ether; ketones such as methyl isobutyl ketone and diisobutyl ketone; amides such as dimethylformamide and dimethylacetamide; ethyl acetate, ethyl cellosolve acetate, 3-methyl -Acetates such as 3-methoxy-1-butanol acetate; aromatic or aliphatic charcoal such as toluene, xylene, hexane, cyclohexane In addition to hydrogen, .gamma.-butyrolactone, N- methyl-2-pyrrolidone, dimethyl sulfoxide and the like.

  The amount of the solvent is preferably added in the range of 50% by weight to 500% by weight, particularly preferably in the range of 80% by weight to 200% by weight, based on the amount of the silicon alkoxide compound. If it is less than 50% by weight, the reaction may run away and gel. On the other hand, if it exceeds 500% by weight, hydrolysis may not proceed.

  In the hydrolysis reaction, an acid catalyst is added to the silicon alkoxide compound in a solvent at a temperature of 15 to 55 ° C., preferably 25 to 35 ° C., for 0.5 to 10 hours, preferably 2 to 5 hours. Preferably it is done.

  As the ultraviolet curable acrylic resin system, a polymer obtained by a polymerization reaction of an ethylenically unsaturated monomer having a saturated hydrocarbon as a main chain is preferable. Examples of the ethylenically unsaturated monomer include esters of polyhydric alcohol and (meth) acrylic acid, such as ethylene glycol di (meth) acrylate, 1,4-cyclohexanedi (meth) acrylate, pentaerythritol tri (meth) acrylate, Pentaerythritol tetra (meth) acrylate, pentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) Examples thereof include acrylate, polyurethane polyacrylate, polyester polyacrylate and the like.

  An initiator may be used for use in the polymerization reaction of the ethylenically unsaturated monomer. Examples of the initiator are those that initiate or promote polymerization and / or crosslinking reaction by radical reaction, anion reaction, cation reaction, etc., and various conventionally known photopolymerization initiators can be used. Specific examples of such photopolymerization initiators include sulfides such as sodium methyldithiocarbamate sulfide, diphenyl monosulfide, dibenzothiazoyl monosulfide and disulfide, thioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, Thioxanthone derivatives such as 2,4-diethylthioxanthone, azo compounds such as hydrazone and azobisisobutyronitrile, diazo compounds such as benzenediazonium salt, benzoin, benzoin methyl ether, benzoin ethyl ether, benzophenone, dimethylaminobenzophenone Michler's ketone, benzylanthraquinone, t-butylanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-aminoanthraquinone, Aromatic carbonyl compounds such as -chloroanthraquinone, dialkylaminobenzoic acid esters such as methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, butyl D-dimethylaminobenzoate, isopropyl p-diethylaminobenzoate, Peroxides such as benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, cumene hydroperoxide, 9-phenylacridine, 9-p-methoxyphenylacridine, 9-acetylaminoacridine, benzacridine, etc. Acridine derivatives, phenazine derivatives such as 9,10-dimethylbenzphenazine, 9-methylbenzphenazine, 10-methoxybenzphenazine, and 6,4 ′, 4 ″ -trimethoxy-2,3-diphenylquinoxaline Quinoxaline derivatives, 2,4,5-triphenylimidazolyl dimer, 2-nitrofluorene, 2,4,6-triphenylpyrylium tetrafluoride boron salt, 2,4,6-tris (trichloromethyl) ) -1,3,5-triazine, 3,3′-carbonylbiscoumarin, thiomichler ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, oligo (2-hydroxy-2-methyl-1- ( 4- (1-methylvinyl) phenyl) propanone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, and the like can be used.

  As the reactive organosilicon compound, an organosilicon compound having a molecular weight of 5000 or less having a polymerizable double bond group, which is reactively crosslinked by heat or ionizing radiation is preferable. Examples thereof include one-end vinyl functional polysilane, both-end vinyl functional polysiloxane, vinyl functional polysilane obtained by reacting these compounds, and vinyl functional polysiloxane.

  The low refractive index layer of the present invention is silica-based to increase the surface hardness and scratch resistance of the low refractive index layer, to lower the refractive index of the low refractive index layer, and to further improve the adhesion to the hard coat layer. It is important to include fine particles. As silica-based fine particles, silica-based fine particles having an average particle diameter of 1 nm to 200 nm can be sufficiently combined with the above-mentioned material forming the low refractive index layer to obtain good hardness, and many particles are introduced. It is preferable because many voids are generated between the particles and a low refractive index can be realized, and the average particle diameter is particularly preferably 1 nm to 70 nm.

  Further, among these silica-based fine particles, those having a structure having a cavity inside are particularly preferably used in order to lower the refractive index. Examples of the silica-based fine particles having cavities therein include silica-based fine particles having cavities surrounded by an outer shell, porous silica-based fine particles having a large number of cavities, and the like. As such an example, it can manufacture by the method currently disclosed by patent 3272111, for example. Further, the refractive index of the fine particles themselves is preferably 1.20 to 1.40, more preferably 1.20 to 1.35. Although a method of measuring the refractive index is described later, it can also be measured by a method disclosed in Japanese Patent Laid-Open No. 2001-233611. As such silica-based fine particles, for example, those disclosed in Japanese Patent Application Laid-Open No. 2001-233611 and those generally marketed such as Japanese Patent No. 3272111 can be used.

  The addition amount of the silica-based fine particles is preferably 20 to 90% by weight based on 100% by weight of the total amount of the low refractive index layer. If it is less than 20% by weight, there is no effect of lowering the refractive index, and if it exceeds 90% by weight, various physical and chemical strengths of the resulting film are lowered, which is not preferable.

  In the present invention, the low refractive index layer is preferably composed mainly of a siloxane polymer bonded to silica-based fine particles in order to achieve both surface scratch resistance and a low refractive index. The main component here means that the siloxane polymer bonded to the silica-based fine particles contains 15% by weight or more with respect to 100% by weight of the total amount of the low refractive index layer. More preferably, the siloxane polymer bonded to the silica-based fine particles contains 20% by weight or more with respect to 100% by weight of the total amount of the low refractive index layer. As will be described later, it is important that the low refractive index layer contains at least one of polyether-modified polydimethylsiloxane and polyester-modified polydimethylsiloxane. Therefore, the siloxane polymer bonded to the silica-based fine particles is preferably 75% by weight or less with respect to 100% by weight of the total amount of the low refractive index layer.

  The term “bond” as used herein means a state in which the silica component of the silica-based fine particles and the siloxane polymer in the matrix are reacted and homogenized. Here, “homogenized” means a state in which the silica component of the silica fine particles and the siloxane polymer of the matrix are reacted and homogenized. The state can be known by observing the boundary between the silica fine particles and the siloxane polymer with a transmission electron microscope (hereinafter simply referred to as TEM).

  That is, FIG. 2 shows an example of a homogeneous state, and FIGS. 3 and 4 show examples of a non-uniform state. 2, 3 and 4 are all cross-sectional TEM photographs of low refractive index layers containing silica particulates having cavities surrounded by an outer shell. In the low refractive index layer 11 of FIG. 2, the white circular shape is the cavity 7 inside the silica-based fine particles. The outer side of the white circle is the outer shell of silica-based fine particles and a siloxane compound. As shown in the figure, both are homogenized, and the boundary between the silica-based fine particles and the siloxane compound is not observed. In FIGS. 3 and 4, the white cavities are the cavities 7 inside the silica-based fine particles. Unlike FIG. 2, in FIGS. 3 and 4, a dark thin layer exists outside the white circle so as to cover it, and a light color matrix exists outside the white circle. The dark-colored thin layer is the outer shell 8 of silica-based fine particles, and the light-colored matrix is the siloxane compound 9. That is, since both are not homogenized, the boundary portion 10 between the silica-based fine particles and the siloxane compound is clearly observed as shown in the figure. That is, in the homogeneous state, as shown in FIG. 2, the boundary between the silica-based fine particles and the siloxane compound is not observed, whereas in the case of non-homogeneous, the silica-based fine particles are used as shown in FIGS. And the boundary part of the siloxane polymer can be clearly observed.

  Such a homogenized state is considered to be because the silica-based fine particles and the siloxane polymer are bonded. Thereby, the dispersion stability of the silica-based fine particles in the siloxane-based paint is improved, and secondary aggregation can be suppressed. Further, when the coating is formed, the surface hardness of the coating is improved because the siloxane polymer as the matrix material and the silica-based fine particles are firmly bonded.

  Such a siloxane-based paint can be obtained by hydrolyzing a silane compound in a solvent with an acid catalyst in the presence of silica-based fine particles to form a silanol compound and then subjecting the silanol compound to a condensation reaction. it can.

  As such a silane compound, a polyfunctional fluorine-containing silane compound is preferably used from the viewpoint of low refractive index and antifouling property. For example, trifluoromethyltrimethoxysilane, trifluoromethyltriethoxysilane, trifluoropropyltrimethoxy Trifunctional fluorine-containing silane compounds such as silane, trifluoropropyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, tridecafluorooctyltrimethoxysilane, heptadecafluorodecyltriethoxysilane, tridecafluorooctyltriethoxysilane, Bifunctional fluorine-containing silane compounds such as heptadecafluorodecylmethyldimethoxysilane are preferably used. From the viewpoint of surface hardness, trifluoromethylmethoxysilane, trifluoromethyl ethoxide, etc. Shishiran, trifluoropropyl trimethoxysilane, trifluoropropyl triethoxysilane, more preferably used.

  Examples of such polyfunctional fluorine-free silane compounds include vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, methyltrimethoxysilane, and methyltriethoxy. Silane, hexyltrimethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxy Trifunctional silanes such as silane, 3-chloropropyltrimethoxysilane, 3- (N, N-diglycidyl) aminopropyltrimethoxysilane, 3-glycidoxysipropyltrimethoxysilane Compound, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-amino Propylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropylmethyldiethoxysilane, cyclohexylmethyldimethoxysilane, 3-methacryloxypropyldimethoxy Bifunctional silane compounds such as silane and octadecylmethyldimethoxysilane, tetrafunctional silane compounds such as tetramethoxysilane and tetraethoxysilane, etc. Any of these are preferably used. From the viewpoint of surface hardness, vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane are used. More preferable.

  In addition, the silica-based fine particles described above are silica-based fine particles having an average particle diameter of 1 nm to 200 nm. In addition to being sufficiently bonded to the matrix material to obtain good hardness, the inter-particle generated by introducing many particles. This is preferable because many voids are generated and a low refractive index can be realized, and the average particle diameter is particularly preferably 1 nm to 70 nm. Further, among these silica-based fine particles, those having a structure having a cavity inside are particularly preferably used in order to lower the refractive index.

  Examples of the silica-based fine particles having cavities therein include silica-based fine particles having cavities surrounded by an outer shell, porous silica-based fine particles having a large number of cavities, and the like. As such an example, it can manufacture by the method currently disclosed by patent 3272111, for example. Further, the refractive index of the fine particles themselves is preferably 1.20 to 1.40, more preferably 1.20 to 1.35. Although a method of measuring the refractive index is described later, it can also be measured by a method disclosed in Japanese Patent Laid-Open No. 2001-233611. As such silica-based fine particles, for example, those disclosed in Japanese Patent Application Laid-Open No. 2001-233611 and those generally marketed such as Japanese Patent No. 3272111 can be used.

  Acid catalysts used for the hydrolysis reaction include acid catalysts such as formic acid, succinic acid, hydrochloric acid, sulfuric acid, acetic acid, trifluoroacetic acid, phosphoric acid, polyphosphoric acid, polyvalent carboxylic acid or anhydrides thereof, and ion exchange resins. It is done. In particular, formic acid and acetic acid are preferably used as catalysts from the viewpoint of improving the hardness of the transparent coating.

  A preferable addition amount of such a catalyst is preferably 0.05% by mass to 10% by mass, and more preferably 0.1% by mass to 5% by mass with respect to the total silane compound content used in the synthesis of the siloxane polymer. It is. If the amount of the acid catalyst is less than 0.05% by mass, the hydrolysis reaction may not proceed sufficiently. Moreover, when it exceeds 10 mass%, there exists a possibility that a hydrolysis reaction may run away.

  In the hydrolysis reaction, it is preferable to perform the reaction in a solvent because the control of the reaction is easy. As the solvent to be used, an organic solvent is preferable, for example, ethanol, propanol, butanol, 3-methyl-3-methoxy. -1-alcohols such as butanol; glycols such as ethylene glycol and propylene glycol; ethers such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether and diethyl ether; ketones such as methyl isobutyl ketone and diisobutyl ketone Amides such as dimethylformamide and dimethylacetamide; Acetates such as ethyl acetate, ethyl cellosolve acetate, 3-methyl-3-methoxy-1-butanol acetate Tate like; toluene, xylene, hexane, other aromatic or aliphatic hydrocarbons such as cyclohexane, .gamma.-butyrolactone, N- methyl-2-pyrrolidone, dimethyl sulfoxide can be used. The amount of the solvent is preferably added in the range of 50% by mass to 500% by mass, more preferably in the range of 80% by mass to 200% by mass with respect to the total silane compound content used at the time of synthesizing the siloxane polymer. It is. If it is less than 50% by mass, the reaction may run away and gel. On the other hand, if it exceeds 500 mass%, hydrolysis may not proceed.

  Moreover, as water used for a hydrolysis, ion-exchange water is preferable. The amount of water can be arbitrarily selected, but it is preferably used in the range of 1.0 to 4.0 mol with respect to 1 mol of silane.

  The hydrolysis reaction is preferably performed at room temperature to 55 ° C by adding the acid catalyst and water in the solvent to the silane compound.

  In the low refractive index layer of the present invention, the conditions for the condensation reaction for obtaining a siloxane polymer that is suitably bonded to the silica-based fine particles are hydrolyzed to obtain a silanol compound, and then the reaction solution is used as it is. It is preferable to carry out for 1 to 100 hours under reflux. In addition, in order to increase the degree of polymerization of the siloxane polymer, it is possible to reheat or add a base catalyst.

  The low refractive index layer that forms the uppermost layer of the antireflection film of the present invention includes a polyether-modified polydimethylsiloxane and a polyester-modified polydimethylsiloxane in order to improve surface resistance such as friction resistance and scratch resistance of the film surface. It is necessary to contain at least one siloxane.

  Commercially available polyether-modified polydimethylsiloxane can be used as the polyether-modified polydimethylsiloxane used in the present invention. As the polyether-modified polydimethylsiloxane, those having a structure in which a polyalkylene oxide group is introduced at the terminal of the polydimethylsiloxane are used. Specifically, BYK-300, BYK-306, BYK-307, BYK-330, BYK-331, BYK-333, BYK-337, BYK-344, BYK- manufactured by Big Chemie Japan Co., Ltd. 378, Granol 410 manufactured by Kyoeisha Chemical Co., Ltd., KF-351 manufactured by Shin-Etsu Chemical Co., Ltd., and the like.

  In the present invention, a commercially available polyester-modified polydimethylsiloxane can be used as the polyester-modified polydimethylsiloxane. Examples of the polyester-modified polydimethylsiloxane include those obtained by introducing a polyester group into a part of the methyl group of dimethylsiloxane. Specific examples include BYK-310 manufactured by Big Chemie Japan Co., Ltd., Granol 410 manufactured by Kyoeisha Chemical Co., Ltd., and the like.

  In the present invention, as the polyether-modified polydimethylsiloxane or polyester-modified polydimethylsiloxane, in particular, a hydroxyl group-containing polydimethylsiloxane is preferably used in order to improve the sound resistance and scratch resistance.

  As the polyether-modified hydroxyl group-containing polydimethylsiloxane used in the present invention, at least one of the terminal hydroxyl group and / or alkoxy group of a polydimethylsiloxane having a hydroxyl group and / or an alkoxy group at at least one terminal is substituted with a hydroxyl group-containing saturated polyether. The polyether modified polydimethylsiloxane etc. which can be mentioned can be mention | raise | lifted. Specific examples include BYK-375 and BYK-377 manufactured by Big Chemie Japan.

  The polyester-modified hydroxyl group-containing polydimethylsiloxane used in the present invention is a polyester in which at least one of a terminal hydroxyl group and / or alkoxy group of a polydimethylsiloxane having a hydroxyl group and / or an alkoxy group at at least one terminal is substituted with a hydroxyl group-containing saturated polyester. Examples thereof include a modified polydimethylsiloxane and / or a polyester-modified hydroxyl group-containing polydimethylsiloxane in which a part of the side chain is substituted with a hydroxyl group-containing polyester. Specific examples include BYK-370 manufactured by Big Chemie Japan.

  The total amount of the polyether-modified and polyester-modified polydimethylsiloxane added is preferably 1 to 10% by weight relative to 100% by weight of the total amount of the low refractive index layer. If it is less than 1% by weight, the sound of frictional noise is not eliminated, and if it exceeds 10% by weight, defects such as whitening occur in the appearance of the resulting film, and various physical and chemical strengths are lowered, which is not preferable.

  In the antireflection film of the present invention, it is necessary to sequentially laminate at least two layers of the hard coat layer and the low refractive index layer on at least one surface of the base film, and the hard coat layer is more preferable than the low refractive index layer. Is located at a position close to the base film, and a low refractive index layer needs to be laminated on the hard coat layer.

  In addition, another layer may be provided between the hard coat layer and the base film as long as the antireflection function is not hindered. From the viewpoint of productivity including the color tone and cost of the reflective color, the base material It is preferable that a hard coat layer is provided on the film and a low refractive index layer is provided thereon. The refractive index measurement method here is as defined later.

In order to impart a desired level of antistatic properties to the antireflection film of the present invention, the surface resistivity of the antireflection film surface measured by the method shown in JIS K6911 is 1 × 10 ¹² Ω / □ or less. It is preferably 1 × 10 ¹¹ Ω / □ or less.

  The antireflection film of the present invention preferably has a total light transmittance of 85% or more and a haze of 1.5% or less because of excellent image clearness when used as an image display device, and more preferably a total light transmission. The rate is 87% or more, and the haze is 1.2% or less.

  As the base film in the present invention, a film that can be formed by melt film formation or solution film formation is preferably used. Specific examples thereof include films made of polyester, polyolefin, polyamide, polyphenylene sulfide, acetate, polycarbonate, acrylic resin, and the like. Among these, a film made of a thermoplastic resin excellent in transparency, mechanical strength, dimensional stability and the like is particularly preferable. In order to use it for image display device applications, it is preferable that the film has at least one selected from polyester, acetate and acrylic resin because it has high light transmittance and low haze value. From the viewpoint of transparency, haze value, and mechanical properties, a film made of a polyester resin is particularly preferably used.

  For example, the total light transmittance shown by JIS K7361-1 of a base film becomes like this. Preferably it is 40% or more, More preferably, it is 60% or more. The haze value of the substrate film is preferably 5% or less, more preferably 3% or less. The use of a base film satisfying both of these conditions is more preferable in terms of sharpness when the obtained planner prevention film is used as a member for an image display device. Further, the upper limit of the light transmittance is about 99.5%, and the lower limit of the haze value is about 0.1%.

  Examples of the polyester preferably used in the present invention include polyethylene terephthalate, polyethylene naphthalate, polypropylene terephthalate, polybutylene terephthalate, and polypropylene naphthalate. Two or more of these may be mixed. In addition, these may be a polyester copolymerized with other dicarboxylic acid components and diol components, but the copolymerization ratio is preferably 25% or more in the degree of crystallinity in a film in which crystal orientation is completed. More preferred is 30% or more, and still more preferred is 35% or more. When the crystallinity is less than 25%, dimensional stability and mechanical strength tend to be insufficient. The crystallinity can be measured by a method described in “Practical Spectroscopy Series (3) Raman Spectroscopy” issued by IPC Corporation.

  When the above-described polyester is used, its intrinsic viscosity (measured in o-chlorophenol at 25 ° C. according to JIS K7367) is preferably 0.4 to 1.2 dl / g, more preferably 0.00. 5 to 0.8 dl / g. When the intrinsic viscosity is less than 0.4 dl / g, the mechanical strength is insufficient, which is not preferable. Further, even if the intrinsic viscosity exceeds this preferable range, not only is the quality excessive, but also the operability during film production is deteriorated, which is economically undesirable.

  Triacetyl cellulose or the like is used as the acetate, and polymethyl methacrylate or the like is used as the acrylic resin.

  The base film used in the present invention may be a composite film having a laminated structure of two or more layers. As the composite film, for example, a composite film that is substantially free of particles in the inner layer portion and provided with a layer containing particles in the surface layer portion, has coarse particles in the inner layer portion, and fine particles in the surface layer portion. And a composite film having a layer in which the inner layer portion contains fine bubbles are used. In the composite film, the polymer constituting the inner layer portion and the surface layer portion may be a chemically different polymer or the same kind of polymer.

  The base film in the present invention has sufficient thermal stability of the film, particularly dimensional stability and mechanical strength, and from the viewpoint of improving the flatness, in the state where the hard coat layer is provided, biaxial stretching is performed. A crystal-oriented film is preferred. The crystal orientation by biaxial stretching means that the thermoplastic film before unstretched, that is, before the crystal orientation is completed, is preferably stretched about 2.5 to 5 times in the longitudinal direction and the width direction, respectively, and then heat-treated. The crystal orientation is completed by the above, and it indicates a biaxial orientation pattern by wide-angle X-ray diffraction.

  The thickness of the base film used in the present invention is appropriately selected according to the use for which the hard coat film of the present invention is used. From the viewpoint of mechanical strength and handling properties, it is preferably 10 to 500 μm, more Preferably it is 20-300 micrometers.

  The base film of the present invention may contain various additives, resin compositions, cross-linking agents and the like within a range that does not impair the effects of the present invention. For example, antioxidants, heat stabilizers, UV absorbers, organic and inorganic particles, pigments, dyes, antistatic agents, nucleating agents, acrylic resins, polyester resins, urethane resins, polyolefin resins, polycarbonate resins, alkyd resins, epoxy resins , Urea resin, phenol resin, silicone resin, rubber resin, wax composition, melamine crosslinking agent, oxazoline crosslinking agent, methylolated, alkylolized urea crosslinking agent, acrylamide, polyamide, epoxy resin, isocyanate compound Aziridine compounds, various silane coupling agents, various titanate coupling agents, and the like can be used.

  Among these, when inorganic particles such as silica, colloidal silica, alumina, alumina sol, kaolin, talc, mica, calcium carbonate, barium sulfate, carbon black, zeolite, titanium oxide, metal fine powder, etc. are added, it is easy to slip. This is particularly preferable since the property and scratch resistance are improved. The average particle size of the inorganic particles is preferably 0.005 to 5 μm, more preferably about 0.05 to 1 μm. The particle diameter here is a value obtained by measurement using a laser diffraction particle size distribution measuring apparatus. The average particle size is 50% distributed particle size. The 50% distribution particle size refers to the particle size where the particle size distribution is 50%. Moreover, the addition amount of the inorganic particles is preferably 0.05 to 20 parts by mass, more preferably 0.1 to 10 parts by mass in 100 parts by mass of the base film.

The base film of the present invention preferably has a configuration in which an easy-adhesion layer is provided on at least one surface for the purpose of improving the adhesion, in order to improve the adhesion with a layer laminated on the easy-adhesion layer. Such an easy-adhesion layer preferably has a refractive index of 1.52 to 1.66, and moreover, (refractive index of the easy-adhesion layer) = {(refractive index of the base film) × (easy-adhesion layer) It is preferable that the refractive index of the layer laminated on the upper layer}} ^1/2 ± 0.02 is satisfied because interference fringes generated when laminated on the easy-adhesion layer can be reduced. Such an easy-adhesion layer is not particularly limited as long as it has excellent adhesion to the layer laminated on the easy-adhesion layer and has the above-mentioned refractive index, but is water-dispersible polyester resin, water-dispersibility A polyurethane resin is preferably used. Moreover, this easy-adhesion layer is applied in the middle of a film forming process, and the method of forming simultaneously with film forming is used preferably, The thickness becomes like this. Preferably it is 0.08-0.20 micrometers.

  Next, the manufacturing method of the antireflection film of this invention is demonstrated.

  FIG. 1 is a schematic cross-sectional view showing an example of a preferred embodiment of the antireflection film of the present invention. An antireflection layer 6 composed of a hard coat layer 2 and a low refractive index layer 1 is laminated on the base film 3, and a near infrared absorption layer is formed on the surface of the base film 3 opposite to the antireflection layer 6. 4 and the adhesion layer 5 are laminated | stacked.

  As a method for providing the hard coat layer 2 and the low refractive index layer 1, any method such as a method of directly laminating on a base film by coating, a method of laminating a layer formed on another base material on a base film by transfer, etc. However, it is preferable to employ a method of directly laminating on a base film by coating from the viewpoint of production stability at an appropriate film thickness and cost.

  As the coating method, various coating methods such as reverse coating method, gravure coating method, rod coating method, bar coating method, die coating method, spray coating method and the like can be used. In forming the layer, a reverse coating method, particularly a reverse coating using a small-diameter gravure roll is preferable from the viewpoint of coating accuracy.

  Moreover, when applying the hard coat layer 2 and the low refractive index layer 1, it is preferable to prepare a coating solution in which the above components are dispersed in a solvent, and apply, dry and cure. Conventionally known various organic solvents can be used as long as they are compounded for improving the properties and can dissolve the resin component. In particular, in the present invention, an organic solvent having a boiling point of 60 to 180 ° C. is preferable from the viewpoints of viscosity stability and drying property of the composition. Specific examples of such organic solvents include methanol, ethanol, isopropyl alcohol, n-butanol, tert-butanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, propylene glycol monomethyl ether, propylene glycol mono Ethyl ether, cyclohexanone, butyl acetate, isopropyl acetone, methyl ethyl ketone, methyl isobutyl ketone, diacetyl acetone, acetyl acetone and the like are preferably used. These may be used alone or in combination of two or more.

  When preparing the coating solution used for forming the hard coat layer 2, the amount of the organic solvent may be any amount so that the composition has a viscosity with good workability according to the coating means and the printing means. The solid content concentration of the composition is usually 60% by mass or less, preferably 50% by mass or less. As the preparation of the composition for forming a photocurable film of the present invention, any method can be adopted, but conductive particles are usually added to a solution in which a resin component is dissolved in an organic solvent, a paint shaker, A method of dispersing by a dispersing machine such as a ball mill, sand mill, three rolls, attritor, homomixer, etc., and then adding a photopolymerization initiator and dissolving it uniformly is suitable.

  When an active ray curable acrylic resin is used as the main component of the hard coat layer 2 in the present invention, the active rays include acrylic, such as ultraviolet rays, electron beams, and radiation (α rays, β rays, γ rays, etc.). An electromagnetic wave for polymerizing the vinyl group is used, and practically, ultraviolet rays are convenient and preferable. As the ultraviolet ray source, an ultraviolet fluorescent lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a xenon lamp, a carbon arc lamp, or the like can be used. Moreover, when irradiating actinic radiation, if it irradiates under a low oxygen concentration, it can harden | cure efficiently.

  The coating liquid used for forming the low refractive index layer 1 of the present invention is preferably composed of the siloxane polymer as a main component, diluted with a solvent by adding a curing agent or the like, and the content of the solvent is used during the synthesis of the siloxane polymer. It is preferable to add in the range of 1300 mass% to 9900 mass%, particularly preferably in the range of 1500 mass% to 6000 mass% with respect to the total silane compound content. If the amount is less than 1300% by mass and exceeds 9900% by mass, it becomes difficult to form a transparent film having a predetermined film thickness.

  As the curing agent, titanium, zirconium, aluminum and magnesium are used. Among these, for the purpose of lowering the refractive index, aluminum-based and magnesium-based curing agents having a low refractive index are preferable. These curing agents can be easily obtained by reacting a metal alkoxide with a chelating agent. Examples of chelating agents include β-diketones such as acetylacetone, benzoylacetone, and dibenzoylmethane; β-keto acid esters such as ethyl acetoacetate and ethyl benzoylacetate.

  Preferable specific examples of the metal chelate compound include ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate), alkyl acetoacetate aluminum diisopropylate, aluminum monoacetyl acetate bis (ethyl acetoacetate), aluminum tris ( Aluminum chelate compounds such as acetylacetonate), magnesium chelate compounds such as ethyl acetoacetate magnesium monoisopropylate, magnesium bis (ethyl acetoacetate), alkyl acetoacetate magnesium monosopropylate, and magnesium bis (acetylacetonate) are used. . Of these, aluminum tris (acetylacetonate), aluminum tris (ethyl acetoacetate), magnesium bis (acetylacetonate), and magnesium bis (ethyl acetoacetate) are preferable, considering storage stability and availability. Then, aluminum tris (acetylacetonate) and aluminum tris (ethylacetoacetate) are particularly preferable. The amount of the metal chelate compound added is preferably 0.1% by mass to 10% by mass, particularly preferably 1% by mass to 6% by mass, based on the total silane compound content used during the synthesis of the siloxane polymer. %. When the amount introduced is less than 0.1% by mass, curing becomes insufficient, and when a transparent film is formed, the hardness decreases. On the other hand, when it exceeds 10% by mass, the curing becomes sufficient and the hardness of the transparent film is improved, but the refractive index is also improved, which is not preferable.

  The near-infrared absorption layer 4 can be provided in the antireflection film of this invention on the surface opposite to the surface which has the antireflection layer 6 of a base film. The near-infrared absorbing layer can be used without any particular limitation, such as those obtained by dispersing a near-infrared absorbing dye in a polymer resin, or provided with a near-infrared absorbing dye alone.

  As the near infrared absorbing dye, for example, a diimonium salt compound, a fluorine-containing phthalocyanine compound, a thionickel complex compound, an aminium compound, a cyanine compound, an azo compound, a polymethine compound, a quinone compound, a diphenylmethane compound, A triphenylmethane compound, a mercaptonaphthol compound, or the like is used, and either a single compound system or a mixed system can be suitably used.

  When the near-infrared absorbing dye is dispersed in a polymer resin, examples of the polymer resin include polyester-based, acrylic-based, cellulose-based, polyethylene-based, polypropylene-based, polyolefin-based, polyvinyl chloride-based, polycarbonate, and phenol-based resins. Urethane resins and the like are used, and any of them can be suitably used, and it is preferable to contain an ultraviolet absorber such as benzophenone or benzotriazole in order to suppress the deterioration of light resistance of the near infrared absorbing dye. Moreover, it is preferable to disperse | distribute 1-10 mass parts near-infrared absorption pigment | dye with respect to 100 mass parts of polymeric resins.

  In the antireflection film of the present invention, an adhesive layer 5 can be provided on the opposite surface of the base film having the antireflection layer 6. The pressure-sensitive adhesive layer 5 is not particularly limited as long as two objects are bonded by their pressure-sensitive adhesive action. As the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer 5, rubber-based, vinyl polymerization-based, condensation polymerization-based, thermosetting resin-based, silicone-based, and the like can be used. Among these, as the rubber-based adhesive, a butadiene-styrene copolymer system (SBR), a butadiene-acrylonitrile copolymer system (NBR), a chloroprene polymer system, an isobutylene-isoprene copolymer system (butyl rubber), or the like may be used. it can. As the vinyl polymerization adhesive, acrylic resin, styrene resin, vinyl acetate-ethylene copolymer system, vinyl chloride-vinyl acetate copolymer system, and the like can be used. As the condensation polymerization pressure-sensitive adhesive, a polyester resin system can be used. As the thermosetting resin-based pressure-sensitive adhesive, an epoxy resin system, a urethane resin system, a formalin resin system, or the like can be used. These resins may be used alone or in combination of two or more.

  Furthermore, as the pressure-sensitive adhesive, either a solvent-type pressure-sensitive adhesive or a solventless pressure-sensitive adhesive can be used. The pressure-sensitive adhesive layer 5 is formed using a conventional technique such as coating using the pressure-sensitive adhesive as described above. Furthermore, you may make the adhesion layer 5 contain a coloring agent. This is easily achieved by mixing and using a colorant such as a pigment or dye in the adhesive. When it contains a colorant, it is desirable that the light transmittance at 550 nm is in the range of 40 to 80% as a laminated film.

Since the antireflection film of the present invention has high surface hardness and scratch resistance, it can be used in a wide range of applications. For example, it can be applied to the surface of membrane switches, curved mirrors, rearview mirrors, goggles, window glass, posters, advertising towers, nameplates and instrument covers, and other various commercial displays. Especially for image display members such as liquid crystal display (LCD), plasma display panel (PDP), electroluminescence display (ELD), cathode ray tube display (CRT), portable digital assistant (PDA), adhesive layer or adhesive layer The image display device can be attached to the surface of the image display surface and / or the front plate thereof via the.
[Characteristic measurement method and effect evaluation method]
The characteristic measurement method and effect evaluation method in the present invention are defined as follows.

(1) Scratch resistance: Steel wool hardness evaluation Scratch resistance was rubbed 10 times at a stroke width of 10 cm and a speed of 30 mm / sec by applying a load of 250 g to # 0000 steel wool on the antireflection surface of the antireflection film. Then, the surface was observed visually and how to get a damage | wound was evaluated in the following five steps.

  5th grade: No scratches.

  Fourth grade: 1 to 5 scratches.

  3rd grade: 6 to 10 scratches.

  Second grade: 11 or more scratches.

  First grade: Countless scratches on the entire surface.

  When it is used for an image display device, it is a pass level if it is any of grade 3, grade 4, and grade 5.

(2) Friction resistance The friction property is determined by whether or not a rubbing noise is generated at a stroke width of 10 cm and a speed of 30 mm / sec when a load of 200 g is applied to the polycarbonate resin as a display member on the antireflection surface of the antireflection film. Evaluation was made in three stages.

◎: No friction sound ○: Very slight friction sound △: A weak sound when rubbing ×: A rubbing noise when rubbing When used for an image display device, at least ◎ or ○ If it is either, it is a pass level.

(3) Total light transmittance and haze measurement Based on JIS K7105, it measured using Nippon Denshoku Industries Co., Ltd. turbidimeter NDH2000. It is desirable that the total light transmittance is 85% or more and the haze value is 1.5% or less.

(4) Reflectance measurement The surface opposite to the measurement surface (the surface on which the antireflection layer is provided) is made of 320-400 water resistant sandpaper so that the 60 ° C. gloss (JIS Z 8741) is 10 or less. After the surface was uniformly roughened, a black paint was applied and colored so that the visible light transmittance was 5% or less.

  Using a spectrophotometer (UV-3150) manufactured by Shimadzu Corporation, the absolute reflection spectrum in the wavelength region of 380 nm to 800 nm was measured at an incident angle of 5 degrees from the measurement surface, and the reflectance at wavelengths of 400 nm and 700 nm The minimum reflectance in the region of 400 nm to 700 nm was determined. When the measured reflection spectrum has undulations, the respective reflectances were obtained from curves connecting intermediate points between undulation peaks (maximum points) and valleys (minimum points). The lower the minimum reflectance, the higher the antireflection function and the better, and 1.1% or less is preferable.

(5) Refractive index measurement About the coating film formed with the spin coater on the silicon wafer, the refractive index of 633 nm was measured with the phase difference measuring apparatus (Nikon Corporation make: NPDM-1000) on 25 degreeC temperature conditions. did.

  Next, although this invention is demonstrated based on an Example, this invention is not necessarily limited to these.

(Preparation of low refractive index paint)
A silica slurry (Suriria manufactured by Catalyst Chemical Industry Co., Ltd.) composed of 144 parts by mass of porous silica particles having a hollow part surrounded by an outer shell having a primary particle diameter of 50 nm and 560 parts by mass of isopropyl alcohol was prepared, and methyltrimethoxysilane was prepared. 219 parts by weight, 3,3,3-trifluoropropyltrimethoxysilane, 158 parts by weight, silica slurry 704 parts by weight, polypropylene glycol monoethyl ether 713 parts by weight, and 1 part by weight of phosphoric acid and 130 parts by weight of water were mixed. The resulting mixture was hydrolyzed with stirring at 30 ° C. ± 10 ° C. for 60 minutes, and the temperature was raised to 80 ° C. ± 5 ° C. for polymerization for 60 minutes to obtain a silica particle-containing polymer.

  Next, after 1200 parts by mass of this silica particle-containing polymer and 5244 parts by mass of isopropyl alcohol were mixed with stirring, 15 parts by mass of acetoxyaluminum was added as a curing catalyst and mixed again with stirring to prepare a low refractive index paint.

  The refractive index of the coating film of the obtained paint was 1.35 (value obtained by the measurement method described in (5) Refractive index measurement).

Example 1
A paint containing 27% by mass of antimony pentoxide fine particles having an average particle size of about 50 nm and urethane acrylate (Toyo Ink Manufacturing Co., Ltd.) on the easy-adhesion surface of a commercially available optically-adhesive polyester film (Lumirror (registered trademark) U46 manufactured by Toray Industries, Inc., 100 μm)) TYS63 manufactured by Co., Ltd .: Coating film refractive index 1.63 (value according to the measurement method described in (5) Refractive index measurement, solid content concentration 40% by mass) is coated with a bar coater and dried at 90 ° C. Thereafter, ultraviolet ray 400 mJ / cm ² was irradiated and cured to provide an A layer having a thickness of about 2 μm.

  Next, 3 parts of polyester-modified hydroxyl group-containing polydimethylsiloxane (BYK370 manufactured by Big Chemie) is added to this A layer with respect to 100 parts of the solid content of the low refractive index paint-1, and the prepared paint is applied with a bar coater. The film was dried and cured at 130 ° C., and a B layer having a thickness of about 0.1 μm was provided to produce an antireflection film. The evaluation results of the obtained antireflection film are shown in Table 1.

  As is clear from Table 1, the friction resistance, scratch resistance, total light transmittance, haze, and minimum reflectance at wavelengths of 400 to 700 nm were also very good.

(Example 2)
Regarding the B layer, anti-reflection was conducted in the same manner as in Example 1 except that the polyester-modified hydroxyl group-containing polydimethylsiloxane contained in the B layer was used as a polyether ester-modified hydroxyl group-containing polydimethylsiloxane (BYK375 manufactured by Big Chemie). A film was produced. The evaluation results of the obtained antireflection film are shown in Table 1.

  As is clear from Table 1, the friction resistance, scratch resistance, total light transmittance, haze, and minimum reflectance at wavelengths of 400 to 700 nm were also very good.

(Example 3)
Reflecting in the same manner as in Example 1 except that the polyester-modified hydroxyl group-containing polydimethylsiloxane contained in the layer B is used for the polyether-modified polydimethylsiloxane (Kyoeisha Chemical Co., Ltd. Granol 410). A prevention film was produced. The evaluation results of the obtained antireflection film are shown in Table 1.

  As is clear from Table 1, the friction resistance, scratch resistance, total light transmittance, haze, and minimum reflectance at wavelengths of 400 to 700 nm were also very good.

(Comparative Example 1)
Regarding the B layer, an antireflection film was produced in the same manner as in Example 1 except that the polyester-modified hydroxyl group-containing polydimethylsiloxane contained in the B layer was not used. The evaluation results of the obtained antireflection film are shown in Table 1.

  As is clear from Table 1, it has reached acceptable levels such as scratch resistance and optical properties, and some of the other properties exhibit good values, but it is not suitable for use because it generates frictional noise and friction noise. It became.

(Comparative Example 2)
Regarding the B layer, an antireflection film was prepared in the same manner as in Example 1 except that the polyester-modified hydroxyl group-containing polydimethylsiloxane contained in the B layer used aralkyl-modified polymethylalkylsiloxane (BYK323 manufactured by Big Chemie). Manufactured. The evaluation results of the obtained antireflection film are shown in Table 1.

  As is apparent from Table 1, the scratch resistance and optical properties were generally good, but the friction resistance did not reach an acceptable level, and there was a problem in use.

(Comparative Example 3)
For the B layer, the polyester-modified hydroxyl group-containing polydimethylsiloxane contained in the B layer is antireflective in the same manner as in Example 1 except that polydimethylsiloxane (KF-96 manufactured by Shin-Etsu Chemical Co., Ltd.) is used. A film was produced. The evaluation results of the obtained antireflection film are shown in Table 1.

  As is apparent from Table 1, the scratch resistance and optical properties were generally good, but the friction resistance did not reach an acceptable level, and there was a problem in use.

Example 4
On the surface of the antireflection film obtained in Example 1, on which the antireflection layer 6 is not provided, two kinds of near infrared absorbing dyes (diimonium salt type: IRG-022 manufactured by Nippon Kayaku Co., Ltd., phthalocyanine type: ( EEX Color 810K manufactured by Nippon Shokubai Co., Ltd.) 1.9 mass% and 1.0 mass%, respectively, and acrylic resin (Mitsubishi Rayon Co., Ltd. Dianar BR-80) 97.1 mass% mixed were used. And provided a near-infrared absorbing layer. Furthermore, on this near-infrared absorbing layer, a dye having an absorption maximum at a wavelength of 595 nm and a dye for correcting the chromaticity of white light are mixed with an adhesive AGR-100 (manufactured by Nippon Kayaku Co., Ltd.) to form an adhesive layer. After being provided and bonded to glass, it was cured with an ultraviolet irradiation amount of 1000 mJ / cm ² to obtain a front protective plate for plasma display.

(Example 5)
The front protective plate for the plasma display panel of Example 4 was set on the front surface of the plasma display panel. A plasma display with little reflection and no frictional noise even when the surface was in contact with the panel was obtained.

  According to the present invention, since the antireflection film of the present invention has a low surface reflectance and does not generate frictional sound, it is applied to, for example, the front surface of a large flat screen television such as a plasma display, the front surface of a liquid crystal television, etc. It is suitable as an antireflection film.

It is sectional drawing which represented typically the cross section which shows an example of the antireflection film of this invention. It is the TEM photograph which expanded B layer of the antireflection film of the present invention at a magnification of 200,000 times. It is the TEM photograph which expanded the B layer which has a silica type fine particle and the siloxane polymer which is not homogenized as a main component by 200,000 times magnification. It is the TEM photograph expanded to 200,000 times which shows another example of B layer which has a silica type microparticle and the siloxane polymer which is not homogenized as a main component.

Explanation of symbols

1: Low refractive index layer 2: Hard coat layer 3: Base film 4: Near-infrared absorption layer 5: Adhesive layer 6: Antireflection layer 7: Internal cavity of silica-based fine particles 8: Outer shell 9 of silica-based fine particles: Siloxane polymer 10: Boundary 11: Low refractive index layer

Claims (10)

An antireflection film in which a hard coat layer containing an acrylic resin and high refractive index particles and a low refractive index layer containing silica-based fine particles are sequentially laminated on at least one surface of a base film,
The antireflective film in which the low refractive index layer forming the uppermost layer of the antireflective film contains at least one of polyether-modified polydimethylsiloxane and polyester-modified polydimethylsiloxane.   The antireflection film according to claim 1, wherein the polyether-modified polydimethylsiloxane and the polyester-modified polydimethylsiloxane contain a hydroxyl group.   The antireflection film according to claim 1 or 2, wherein the total amount of the polyether-modified polydimethylsiloxane and the polyester-modified polydimethylsiloxane is 1 to 10% by weight with respect to 100% by weight of the total amount of the low refractive index layer. .   The antireflection film according to any one of claims 1 to 3, wherein the low refractive index layer contains a siloxane polymer combined with silica-based fine particles as a main component. The antireflection film according to claim 4, wherein the silica-based fine particles have cavities therein.   The antireflective film according to claim 1, wherein the low refractive index layer has a refractive index of 1.30 or more and 1.40 or less.   The high refractive index particle is at least one oxide selected from the group consisting of zinc, titanium, aluminum, cerium, yttrium, niobium, zirconium, antimony, indium, and tin. The antireflection film as described.   The antireflective film according to claim 1, wherein the hard coat layer has a refractive index of 1.50 or more and 1.70 or less.   The antireflection film according to any one of claims 1 to 8, wherein the base film is made of at least one selected from the group consisting of a polyester resin, an acetate resin, and an acrylic resin.   The image display apparatus with which the antireflection film in any one of Claims 1-9 is affixed on the surface of an image display surface or a front plate.