KR20070095418A - Reflection preventing film - Google Patents

Abstract

On one surface of a base material film, (A) a hard coat layer, which includes a cured resin cured by active energy beam irradiation, and a near infrared ray absorbent, and has a thickness of 2-20Vm, and (B) a low refraction index layer, which includes a cured resin cured by active energy beam irradiation, and has a refraction index of 1.43 or less, and a thickness of 50-200nm, are successively stacked. The reflection preventing film has a transmittance of 30% or less at least over the entire area having a wavelength of 850-1000nm. The film is provided with a near infrared ray absorbing characteristic and a reflection preventing characteristic, is excellent in abrasion resistance, suitably used especially for PDP, has a simple layer constitution and can be manufactured by wet-process at low cost.

Description

Anti-reflective film {REFLECTION PREVENTING FILM}

The present invention is an antireflection film, more specifically, having near-infrared absorption performance and antireflection performance, and excellent in scratch resistance, simple layer structure, low cost, and particularly suitable for plasma display. It relates to a prevention film.

In an image display device such as a plasma display (PDP), a cathode ray tube (CRT), a liquid crystal display (LCD), light is incident on the screen from outside, and the light is reflected to make the display image difficult to see. In recent years, with the enlargement of a display, solving the said problem becomes an increasingly important subject.

In order to solve such a problem, various antireflection processing and anti-glare processing have been adopted so far for various displays. As one example, the use of antireflection films in various displays has been carried out.

This antireflection film is conventionally a method of thinning a low refractive index material (MgF ₂ ) on a base film by a dry process such as vapor deposition or sputtering, or a material having a high refractive index [ITO ( Tin-doped indium oxide), TiO _2, etc.] and materials having low refractive index (MgF ₂ , SiO _2, etc.) are produced alternately. However, the antireflection film produced by such a dry method has a problem that manufacturing costs cannot be avoided.

Therefore, recently, it has been attempted to produce an antireflection film by a wet process, that is, by wet coating. However, in the antireflection film produced by this wet method, there is a problem that the scratch resistance of the surface is poor as compared with the antireflection film by the dry method described above.

Therefore, in order to solve the said problem in a wet method, forming a hardened layer (hard coating layer) using the ionizing radiation curable resin composition is performed. For example, on the base film, (1) (A) hard coating layer of 2-20 micrometers in thickness containing hardening resin by ionizing radiation, (B) hardening resin by ionizing radiation, and antimony doped tin oxide containing A high refractive index layer having a thickness of 60 to 160 nm containing at least two metal oxides and having a refractive index in the range of 1.65 to 1.80, and (C) a siloxane polymer, and having a refractive index in the range of 1.37 to 1.47. Optical film (for example, refer patent document 1) formed by laminating | stacking the low refractive index layer of 80-180 nm sequentially, (2) (A) Thickness containing metal oxide and hardened | cured material by heat or ionizing radiation An optical film comprising a hard coating layer having a thickness of 2 to 20 μm, and (B) a low refractive index layer having a thickness of 40 to 200 nm in a range of 1.30 to 1.45, in which porous silica and a polysiloxane polymer are sequentially stacked ( For example, Patent Document 2) and the like are disclosed.

These optical films are antireflection films that effectively prevent reflection of light on the surface of an image display element and are excellent in scratch resistance.

By the way, PDP is an apparatus which excites the molecule | numerator of xenon gas sealed by the plasma discharge between electrodes, excites fluorescent substance by the ultraviolet-ray which generate | occur | produces, and emits light of visible region, and displays an image. In the PDP, since light emission uses plasma discharge, unnecessary electromagnetic waves of about 30 to 130 MHz are leaked to the outside, so that other devices (for example, information processing apparatuses, etc.) are not adversely affected. It is required to suppress electromagnetic waves as much as possible.

In the PDP, it is known to emit near infrared rays. This near-infrared light acts on surrounding electronic devices such as a wireless telephone and a video deck using a near-infrared remote control device, which may hinder normal operation. It is required to cut off the near-infrared light as much as possible.

In addition, in the PDP, since the display surface is flat, when light is incident from the outside, light reflected from a wide range enters the eye at the same time, and the screen is hard to be seen, and light reflection prevention from the outside is necessary. Do. In addition, it is also important to transmit the PDP light emission at a predetermined transmittance so that good screen display is performed and color tone correction of the light emission color is performed.

In the PDP, in response to these demands, a front plate having at least three functional films of (1) electromagnetic wave blocking film, (2) near-infrared absorbing film, and (3) anti-reflection film is generally used on the display screen. The treatment which arrange | positions so that an antireflection film may become the most surface (viewer side) is calculated | required (for example, refer patent document 3). In such a case, at least three functional films must be produced and bonded to each other, and the cost cannot be avoided.

On the other hand, in recent years, in terms of cost reduction, the antireflection film on the outermost surface is formed with a near infrared absorption layer on the surface opposite to the antireflection layer of the base material, so that one film has antireflection performance and near infrared absorption performance. The functional film which combines is developed. When manufacturing such a functional film, there are two methods of (1) formation of a near-infrared absorption layer on the back surface of an antireflection film, and (2) formation of an anti-reflection layer on the back surface of a near infrared absorption film. Since loss of film occurs, the effect of cost reduction is small.

[Patent Document 1]

Japanese Patent Application Laid-Open No. 2002-341103

[Patent Document 2]

JP 2003-139908 A

[Patent Document 3]

Japanese Patent Application Laid-Open No. 11-126024

Under the circumstances, the present invention has near infrared absorption performance and antireflection performance, and also has excellent scratch resistance, simple layer structure, low cost, and especially anti-reflection by wet method, which is very suitable for PDP. It aims at providing a film.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched in order to develop the antireflective film which has the said desirable property, and, as a result, at least the wavelength of 850-1000 nm of the antireflective film obtained in the hard-coat layer which is essential in the antireflection film by a wet method. By containing a near-infrared absorber so that the transmittance | permeability in a whole area may be below a certain value, it discovered that the objective can be achieved and came to complete this invention based on this knowledge.

That is, the present invention,

(1) One side of the base film contains a hard coating layer having a thickness of 2 to 20 µm containing (A) hardening resin by active energy ray irradiation and a near infrared absorber, and (B) hardening resin by active energy ray irradiation. An antireflection film having a refractive index of 1.43 or less and a low refractive index layer having a thickness of 50 to 200 nm being sequentially stacked, and having a transmittance of at least 30% in the entire region having a wavelength of 850 to 1000 nm,

(2) The antireflection film according to the above (1), wherein the near infrared absorber in the layer (A) is a tungsten oxide compound,

(3) The antireflection film according to the above (2), wherein the tungsten oxide compound is cesium-containing tungsten oxide,

(4) The antireflection film according to any one of (1) to (3) above, wherein the layer (A) contains at least one filler selected from the group consisting of an organic filler and an inorganic filler,

(5) The antireflection film according to any one of (1) to (4), wherein the layer (B) contains 30 to 80% by weight of porous silica,

(6) The antireflection film according to any one of (1) to (5), wherein the other side of the base film has an adhesive layer having a thickness of 5 to 50 µm, and

(7) the antireflection film according to any one of (1) to (6), which is for a plasma display;

To provide.

According to the present invention, it is possible to provide an antireflection film by a wet method which has near infrared absorption performance and antireflection performance, and is excellent in scratch resistance, and has a simple layer structure and low cost, and is particularly suitable for PDP. have.

The antireflection film of the present invention has a structure in which a hard coating layer containing (A) a near infrared absorber and (B) a low refractive index layer are sequentially stacked on one surface of a base film by a wet method.

There is no restriction | limiting in particular about the base film in the antireflection film of this invention, It can select suitably from a plastic film known as a base material of a conventional antireflection film, and can use. As such a plastic film,

For example, polyester films, such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, a polyethylene film, a polypropylene film, a cellophane, a diacetyl cellulose film, a triacetyl cellulose film, an acetyl cellulose butyrate film, a poly Vinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyetheretherketone film, polyethersulfone film, Polyetherimide film, polyimide film, fluororesin film, polyamide film, acrylic resin film, norbornene-based resin film, cycloolefin resin film and the like.

These base films may be either transparent or semitransparent, may be colored, or may be non-colored, and may be appropriately selected depending on the intended use.

Although the thickness of these base films does not have a restriction | limiting in particular, Although it selects suitably, it is 15-250 micrometers normally, Preferably it is the range of 30-200 micrometers. Moreover, this base film can be surface-treated by the oxidation method, an uneven | corrugated method, etc. to one side or both sides as needed, for the purpose of improving adhesiveness with the layer formed in the surface. Examples of the oxidation method include corona discharge treatment, chromic acid treatment (wet), flame treatment, hot air treatment, ozone and ultraviolet irradiation treatment, and the like. The unevenness treatment method includes, for example, a sandblasting method and a solvent treatment method. Can be mentioned. Although these surface treatment methods are suitably selected according to the kind of base film, in general, the corona discharge treatment method is used preferably from a viewpoint of an effect, operability, etc. Moreover, what gave the primer treatment to one side or both sides can also be used.

In the antireflection film of the present invention, at least one surface of the base film is first formed with a hard coating layer containing a curable resin (A) by active energy ray irradiation and a near infrared absorber.

The hard coating layer containing the cured resin and the near infrared absorber by the active energy ray irradiation includes, for example, an active energy ray curable compound, the above-mentioned near infrared absorber, a photopolymerization initiator, and the like, as desired. It can form by coating to one side of a base film, forming a coating film, irradiating an active energy ray, and hardening the said coating film.

Here, an active energy ray curable compound refers to the compound which has both energy in an electromagnetic wave or a charged particle beam, ie, the compound which bridge | crosslinks and hardens | cures by irradiating an ultraviolet-ray or an electron beam.

As such an active energy ray curable compound, an active energy ray polymerizable prepolymer and / or an active energy ray polymerizable monomer are mentioned, for example. The active energy ray polymerizable prepolymers include a radical polymerization type and a cationic polymerization type, and examples of the active energy ray polymerizable prepolymers, which are radical polymerization types, include polyester acrylates, epoxy acrylates, urethane acrylates, and polyols. An acrylate type etc. are mentioned. Here, as a polyester acrylate type prepolymer, the hydroxyl group of the polyester oligomer which has a hydroxyl group in both terminal parts obtained by condensation of polyhydric carboxylic acid and a polyhydric alcohol, for example by esterification with (meth) acrylic acid, or a polyhydric carboxylic acid The hydroxyl group of the terminal part of the oligomer obtained by adding an alkylene oxide can be obtained by esterifying with (meth) acrylic acid.

An epoxy acrylate type prepolymer can be obtained by, for example, reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol-type epoxy resin or a novolak-type epoxy resin. A urethane acrylate type prepolymer can be obtained by esterifying the polyurethane oligomer obtained by reaction of a polyether polyol, polyester polyol, and polyisocyanate, for example with (meth) acrylic acid. Moreover, a polyol acrylate type prepolymer can be obtained by esterifying the hydroxyl group of a polyether polyol with (meth) acrylic acid. One kind of these active energy ray polymerizable prepolymers may be used, or two or more kinds thereof may be used in combination.

On the other hand, epoxy type resin is normally used as an active energy ray polymerizable prepolymer of cation polymerization type. As this epoxy resin, it is obtained by oxidizing the compound epoxidized by epichlorohydrin, a linear olefin compound, or a cyclic olefin compound with polyhydric phenols, such as a bisphenol resin and a novolak resin, for example with a peroxide etc. Compounds and the like.

As an active energy ray polymerizable monomer, 1, 4- butanediol di (meth) acrylate, 1, 6- hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene, for example Glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxy pivalate neopentyl glycol di (meth) acrylate, dicyclopentanyldi (meth) acrylate, caprolactone modified dicyclopente Nyldi (meth) acrylate, ethylene oxide modified phosphate di (meth) acrylate, allylated cyclohexyldi (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylic Latent, dipentaerythritol tri (meth) acrylate, propionic acid-modified dipentaerythritol tri (meth) acrylate, pentaerythritol Tol tri (meth) acrylate, propylene oxide modified trimetholpropane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa And polyfunctional acrylates such as (meth) acrylate and caprolactone-modified dipentaerythritol hexa (meth) acrylate. 1 type of these active energy ray polymerizable monomers may be used, may be used in combination of 2 or more type, and may be used together with the said active energy ray polymerizable prepolymer.

As a photoinitiator used as needed, about the active energy ray polymerizable prepolymer and active energy ray polymerizable monomer which are radical polymerization type, For example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, Benzoin-n-butyl ether, benzoin isobutyl ether, acetphenone, dimethylaminoacetphenone, 2,2-dimethoxy-2-phenylacetphenone, 2,2-diethoxy-2-phenylacetphenone , 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino- Propane-1-one, 4- (2-hydroxyethoxy) phenyl-2 (hydroxy-2-propel) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, Dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-terthasly-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone , 2-ethyl thioxanthone, 2-chlorothioxanthone, 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, benzyl dimethyl ketal, acetphenone dimethyl ketal, p-dimethyl Amine benzoic acid ester etc. are mentioned. Moreover, as a photoinitiator for the cation polymerization type photopolymerizable prepolymer, Onium, such as aromatic sulfonium ion, aromatic oxo sulfonium ion, and aromatic iodonium ion, for example, tetrafluoroborate, hexafluorophosphate, and hexafluoro antimonate And compounds consisting of anions such as hexafluoroarsenate. These may be used 1 type, or may be used in combination of 2 or more type, and the compounding quantity is 0.2-10 weight normally with respect to 100 weight part of said active energy ray polymerizable prepolymers and / or active energy ray polymerizable monomers. It is chosen from a range of wealth.

On the other hand, the near-infrared absorber contained in the hard coating layer may be one that can be provided with an antireflection film having a transmittance of 30% or less in the entire region having a wavelength of at least 850 to 1000 nm, and is not particularly limited. It can select suitably and can use.

The near-infrared absorbers can be broadly classified into organic near-infrared absorbers and inorganic near-infrared absorbers. Here, as an organic near-infrared absorber, a cyanine type compound, a squarylium type compound, a thiol nickel complex salt type compound, a naphthalocyanine type compound, a phthalocyanine type compound, a triallyl methane type compound, a naphthoquinone type compound, an anthraquinone type compound, Furthermore, perchlorate of N, N, N ', N'- tetrakis (p-di-n-butylaminophenyl) -p-phenylenediamine, chlorine salt of phenylenediamine, phenylenediamide Amino compounds, such as hexafluoroantimonium salt of nium, fluoroborate salt of phenylenediamine, fluoride salt of phenylenedinium, perchlorate salt of phenylenediamine, copper compound, bisthiourea compound, phosphorus compound and The phosphorus ester compound obtained by reaction of a copper compound, a phosphate ester compound, and a copper compound, etc. are mentioned.

Among them, thiol nickel complex salt-based compounds (Japanese Patent Laid-Open No. 9-230134, etc.) and phthalocyanine-based compounds are preferable. In particular, fluorine-containing phthalocyanine compounds disclosed in Japanese Patent Laid-Open No. 2000-26748 or the like are organic-based. Among the near-infrared absorbents, the visible light transmittance is high, and excellent in heat resistance, light resistance, weather resistance and the like, and therefore, they are very suitable.

As the inorganic near infrared absorber, for example, a tungsten oxide compound, titanium oxide, zirconium oxide, tantalum oxide, niobium oxide, zinc oxide, indium oxide, tin-doped indium oxide (ITO), tin oxide, antimony-doped oxide, etc. Tin (ATO), cesium oxide, zinc sulfide and the like. Among these, tungsten oxide-based compounds are preferred because of their high near-infrared absorptivity and high visible light transmittance, particularly cesium-containing tungsten oxide.

In general, when the organic near infrared absorber and the inorganic near infrared absorber are compared, the absorption ability of the near infrared is excellent in the organic type, but the inorganic type in the light resistance and weather resistance is remarkably excellent. Moreover, the thing of the organic type also has the drawback that it is easy to color, and from a practical point of view, the thing of an inorganic near-infrared absorber is preferable, and the use of cesium containing tungsten oxide is especially preferable. The inorganic infrared absorber preferably has a particle size of preferably 0.5 μm or less, more preferably 0.1 μm or less in order to form a transparent coating layer with low absorption in the visible light region.

In this invention, 1 type of organic near-infrared absorbers may be used, may be used in combination of 2 or more type, and 1 type of inorganic near-infrared absorbers may be used, and may be used in combination of 2 or more type. Or you may use suitably combining 1 or more types of organic near-infrared absorbers, and 1 or more types of inorganic near-infrared absorbers.

In addition, when using a near-infrared absorber alone, even if there exists a part which transmittance exceeds 30% in the area | region of wavelength 850-1000 nm, the transmittance | permeability in the whole area | region of wavelength 850-1000 nm by using 2 or more types together This may be 30% or less.

Although the usage-amount of this near-infrared absorber also depends on the film thickness of a hard-coat layer, when using an organic near-infrared absorber, content in a hard-coat layer is 1-10 weight% normally, Preferably it is 3-7 weight%. On the other hand, when using an inorganic near-infrared absorber, content in a hard-coat layer is 10 to 60 weight% normally, Preferably it is 20 to 40 weight%.

In this invention, at least 1 filler chosen from the group which consists of an organic filler and an inorganic filler can be contained in the hard-coat layer of (A) layer as an anti-glare imparting agent. Examples of the organic filler include melamine resin particles, acrylic resin particles, acrylic-styrene copolymer particles, polycarbonate particles, polyethylene particles, polystyrene particles, benzoguanamine resin particles, and the like. The average particle diameter of these organic fillers is about 2-10 micrometers normally.

Examples of the inorganic fillers include silica particles having an average particle diameter of about 0.5 to 10 µm and aggregates of amine compounds of colloidal silica particles, and those having an average particle diameter of about 0.5 to 10 µm.

These anti-glare imparting agents may be used individually by 1 type, or may be used in combination of 2 or more type, and the said content in a hard coat layer is 2 to 15 weight% normally, Preferably it is 3 to 8 weight%. By containing an anti-glare imparting agent in the hard coat layer, the 60 ° gross value of the antireflection film of the present invention is usually 30 to 120.

The coating liquid for hard-coat layer formation used in this invention is the said active-energy-ray-curable compound, a near-infrared absorber, and said photoinitiator, anti-glare imparting agent used as needed in a suitable solvent as needed. Furthermore, various additives, such as antioxidant, a ultraviolet absorber, a light stabilizer, a leveling agent, an antifoamer, etc., can be prepared by adding, melt | dissolving, or disperse | distributing respectively at a predetermined ratio.

Examples of the solvent used at this time include aliphatic hydrocarbons such as hexane, heptane and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, methanol, ethanol, propanol, butanol and 1-methoxy. Alcohols such as 2-propanol, ketones such as acetone, methyl ethyl ketone, 2-pentanone, methyl isobutyl ketone, isophorone, esters such as ethyl acetate and butyl acetate, and cellosolve solvents such as ethyl cellosolve Can be mentioned.

As a density | concentration and a viscosity of a coating liquid prepared in this way, what is necessary is just the density | concentration which can be coated, and a viscosity, and there is no restriction | limiting in particular and it can select suitably according to a situation.

Next, the coating liquid is applied to one surface of the base film using a conventionally known method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like. After coating, it forms a coating film, and after drying, it irradiates an active energy ray and hardens the said coating film, and a near-infrared absorptive hard coat layer is formed.

As an active energy ray, an ultraviolet-ray, an electron beam, etc. are mentioned, for example. The ultraviolet light can be obtained by a high pressure mercury lamp, a fusion H lamp, a xenon lamp, or the like. On the other hand, an electron beam can be obtained by an electron beam accelerator or the like. Among these active energy rays, ultraviolet rays are particularly suitable. Moreover, when using an electron beam, a cured film can be obtained without adding a polymerization initiator.

In the present invention, the thickness of the (A) hard coat layer is in the range of 2 to 20 µm. If the thickness is less than 2 µm, the scratch resistance of the antireflection film obtained may not be sufficiently exhibited. If the thickness exceeds 20 µm, cracks may occur in the hard coat layer. The preferable thickness of this hard coat layer is the range of 3-15 micrometers, and the range of 5-10 micrometers is especially suitable.

In the optical film of this invention, the refractive index of this (A) hard coat layer is 1.47-1.60 normally, Preferably it is the range of 1.49-1.55.

In the antireflection film of the present invention, a low refractive index layer containing a cured resin and porous silica particles by (B) active energy ray irradiation is formed on the hard coat layer.

The low refractive index layer containing the cured resin and the porous silica particles by the active energy ray irradiation is, for example, for forming the low refractive index layer containing the active energy ray curable compound, the porous silica particles, and a photopolymerization initiator if desired. It can form by coating a coating liquid on (A) hard-coat layer, forming a coating film, irradiating an active energy ray, and hardening the said coating film.

About the said active energy ray curable compound and the photoinitiator used according to desire, it is as showing in description of the (A) hard-coat layer mentioned above.

As the porous silica particles contained in the layer (B), those having specific gravity of 1.7 to 1.9, refractive index of 1.25 to 1.36 and an average particle diameter of 20 to 100 nm are preferably used. By using porous silica particles having such properties, an antireflection layer having excellent antireflection performance can be obtained with an antireflection film of one layer type.

In this invention, content of the porous silica particle in this (B) layer becomes like this. Preferably it is selected in 30 to 80 weight% of range. When content of the said porous silica particle exists in the said range, the said (B) layer will become a layer which has a desired low refractive index, and the antireflective film obtained will become excellent in antireflection. Preferable content of the said porous silica particle is 50 to 80 weight%, and the range of 60 to 75 weight% is especially preferable.

The layer (B) has a thickness of 50 to 200 nm and a refractive index of 1.43 or less, preferably in the range of 1.30 to 1.42. When the thickness and refractive index of the layer (B) are within the above ranges, an antireflection film excellent in antireflection performance and scratch resistance can be obtained. The thickness of the layer (B) is preferably 70 to 130 nm, and the refractive index is preferably in the range of 1.35 to 1.40.

The coating liquid for low refractive index layer formation used in the present invention is the active energy ray-curable compound, the porous silica particles, and the photopolymerization initiator described above, if desired, in a suitable solvent. Various additives, for example, antioxidants, ultraviolet absorbers, light stabilizers, leveling agents, antifoaming agents, and the like, can be prepared by adding and dissolving or dispersing, respectively, in predetermined ratios.

About the solvent used at this time, it is as showing in the description of the coating liquid for hard-coat layer formation mentioned above.

As a density | concentration and a viscosity of a coating liquid prepared in this way, what is necessary is just the density | concentration which can be coated, and a viscosity, and it does not restrict | limit especially, It can select suitably according to a situation.

(A) The coating liquid is coated on the hard coating layer by using a conventionally known method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like. After forming a coating film and drying it, an active energy ray is irradiated to harden the said coating film, and (B) low refractive index layer is formed.

The active energy ray is as described in the above description of the hard coat layer.

In this invention, it is advantageous to perform formation of the said (A) hard coat layer and (B) low refractive index layer by the method shown below.

First, a coating film for forming a hard coat layer is coated on one surface of the base film to form a coating film, and irradiated with active energy rays to cure in a half-cure state. At this time, when irradiating an ultraviolet-ray, light quantity is about 50-150mJ / cm <2> normally. Next, a coating film for forming a low refractive index layer is coated on the cured layer formed in this manner to form a coating film, and the active energy ray is sufficiently irradiated to completely cure together with the cured layer in the half cured state. . At this time, when irradiating an ultraviolet-ray, light quantity is about 400-100000mJ / cm <2> normally. In addition, when (A) hard-coating layer and / or low refractive index layer are fully hardened | cured, active energy ray can be irradiated in atmosphere, such as nitrogen gas, in order to prevent hardening inhibition by oxygen. In this case, the oxygen concentration is preferably low, and preferably 2% by volume or less.

In this way, (A) near-infrared absorptive hard coat layer and (B) low refractive index layer which are excellent in adhesiveness between (A) layer and (B) layer are formed on a base film sequentially.

In the antireflection film of the present invention produced in this manner, it is necessary that at least the transmittance in the entire region having a wavelength of 850 to 1000 nm is 30% or less. If the transmittance is 30% or less, when the anti-reflection film of the present invention is used for the front panel of the PDP, the peripheral electronic devices generated by the near-infrared light generated from the PDP (for example, a radiotelephone, a near-infrared remote control device are used). Malfunction of the video deck, etc.) can be suppressed. The transmittance is preferably 20% or less.

Moreover, the reflectance in wavelength 500-700 nm is 3% or less normally, and the total light transmittance is 40% or more normally, Preferably it is 50% or more. Moreover, haze value is usually less than 3%, and when a hard-coat layer contains an anti-glare imparting agent, it is about 3 to 30%.

In the antireflection film of the present invention, an antifouling coating layer can be formed on the (B) low refractive index layer. In general, the antifouling coating layer is a coating liquid containing a fluorine resin using a conventionally known method such as a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like. And (B) it can be formed by coating on a low refractive index layer, forming a coating film, and drying.

The thickness of this antifouling coating layer is 1-10 nm normally, Preferably it is the range of 3-8 nm. By forming the antifouling coating layer, the antireflection film obtained has a good lubricity on the surface and is not easily contaminated.

In this way, it is possible to obtain an antireflection film having both near infrared absorption performance and antireflection performance, not only excellent scratch resistance but also simple layer structure and low cost. This antireflection film is particularly suitably used for the front plate of the PDP.

In the antireflection film of the present invention, an adhesive layer for adhering to the adherend in the front plate can be formed on the surface opposite to the hard coat layer of the base film. For example, an acrylic pressure sensitive adhesive, a urethane pressure sensitive adhesive, or a silicone pressure sensitive adhesive is preferably used. The thickness of this adhesive layer is the range of 5-50 micrometers normally. This adhesive layer can be made to contain dye and a pigment in order to color-correct the light emission color of a display apparatus.

Moreover, a peeling film can be formed on this adhesive layer. As this peeling film, what apply | coated the peeling agent, such as silicone resin, to paper, such as glassine paper, coated paper, laminated paper, and various plastic films, etc. are mentioned, for example. Although there is no restriction | limiting in particular about the thickness of this peeling film, Usually, it is about 20-150 micrometers.

The antireflection film of this invention can be used suitably as an antireflection film for displays, especially a PDP.

Next, although an Example demonstrates this invention in detail, this invention is not limited at all by these examples.

In addition, the physical property of the antireflection film obtained by each example was measured by the method shown below.

(1) Reflectance at wavelength 500 nm, 600 nm and 700 nm

The reflectance in wavelength 500nm, 600nm, and 700nm was measured with the spectrophotometer ("UV-3101PC" by Shimadzu Corporation).

(2) Spectral transmittance at wavelength 850-1000 nm

The spectrophotometer (hereinafter referred to as transmittance) at a wavelength of 850 nm to 1000 nm was measured with a spectrophotometer ("UV-3101PC" manufactured by Shimadzu Corporation). Table 1 shows measured values of wavelengths 850 nm, 900 nm, and 1000 nm.

(3) Total light transmittance and haze

It measured according to JIS K 6714 using the haze meter "NDH 2000" by the Nippon Denshoku Kogyo Co., Ltd. product.

(4) 60 ° gross

Nippon Denshoku Industries Co., Ltd. gross meter "VG 2000" was used, and it measured based on JISK7105.

(5) scratch resistance

Steel wool # 0000 was used, and after reciprocating and rubbing five times at a load of 9.8 × 10 ⁻³ N / mm 2, visual observation was performed and evaluated according to the following criteria.

○: no scratch

×: scratches

Example 1

(1) Preparation of A liquid (coating liquid for hard coating layer formation)

As the active energy ray-curable compound, 100 parts by weight of a polyfunctional acrylate mixture [Arakawa Kagaku Co., Ltd., product name "Beamset 577CB", solid content concentration 100%], a photopolymerization initiator [Ciba Specialty Chemicals inc. ), Brand name "Irgacure 907", 2 parts by weight are added, followed by a near-infrared absorber [Sumitomokinzoku Kozan Co., Ltd. product, a brand name "YMF-01", cesium-containing tungsten oxide (tungsten for tungsten) 33 wt% content) 10 wt% suspension, 14 wt% total solids concentration] After mixing 300 parts by weight, the mixture is diluted with methyl isobutyl ketone (MIBK) so that the total solids concentration is 30 wt%. Coating liquid for coating layer formation) was prepared.

(2) Preparation of B liquid (coating liquid for low refractive index layer formation)

5 parts by weight of a photopolymerization initiator [Shiba Specialty Chemicals, product name "Igacure 907"] to 100 parts by weight of a polyfunctional acrylate mixture (Arakawa Kagaku Co., Ltd. product, "Bamset 577CB", solid content concentration 100%). Part is added, followed by methyl isobutyl ketone (MIBK) dispersion of porous silica particles [Shoku Bai Chemical Co., Ltd. product, brand name "ELCOM RT-1002SIV", solid content concentration 21% by weight, porous silica particles: specific gravity 1.8, Refractive index 1.30, average particle diameter 60 nm] After mixing 1200 parts by weight, the mixture was diluted with MIBK such that the total solid concentration was 2% by weight to prepare a liquid (B) (coating solution for forming a low refractive index layer).

(3) Preparation of antireflection film

A substrate obtained by curing the liquid A obtained in the above (1) on the surface of a double-sided reverse-adhesive polyethylene terephthalate (PET) film (Toyo Boseki Co., Ltd., trade name "A4300") having a thickness of 100 탆 as the base film. It applied with Mayer bar No.16 so that thickness might be 6 micrometers. Next, after drying for 1 minute at 9O <0> C, ultraviolet rays were irradiated with a light quantity of 100mJ / cm &lt; 2 &gt; and cured in a half-cure state.

Next, B half solution obtained in the above (2) was applied to this half cure surface in Mayyaba No. 4 so that the thickness after curing became 100 nm. Next, after drying at 80 ° C. for 1 minute, under UV gas atmosphere (oxygen concentration of 0.5% by volume), ultraviolet rays were irradiated at a light dose of 50OmJ / cm 2, completely cured, and a near-infrared absorptive hard coating layer having a refractive index of 1.54 on the PET film. And a low refractive index layer having a refractive index of 1.38 were sequentially formed to produce a reflective paper film.

The physical properties of the antireflective film thus produced are shown in Table 1. The transmittance | permeability in the whole area | region of wavelength 850-1000 nm of this antireflection film was 30% or less.

In addition, the thickness of each coating layer was measured by the FILMETRICS F-20 by Matsushita Intertech Co., Ltd., and the refractive index is the Abbe refractometer (Na light source, wavelength: about 590 nm) made by Atago Co., Ltd. Measured by (hereinafter, same)

Example 2

It carried out similarly to Example 1 except having changed the preparation of A liquid (coating liquid for hard coat layer formation) in Example 1 as follows.

<Preparation of A Amount>

To 100 parts by weight of a polyfunctional acrylate mixture (Arakawa Kagaku Co., Ltd., product name "Beamset 577 CB", solid content concentration 100%), a photoinitiator [Shiba Specialty Chemicals, product name "Igacure 907"] 2 After adding a weight part, a near-infrared absorber [Nippon Shokubai Co., Ltd., brand name "EX Color IR-12", a phthalocyanine system, 100% of solid content concentration (powder)] 1.3 weight part, a near-infrared absorber (Nippon Co., Ltd.) Shokubai product, brand name "EX color IR-14", phthalocyanine system, solid content concentration 100% (powder)] 0.75 weight part, near infrared absorber [Nippon Shokubai product, brand name "EX color IR-906B" , Phthalocyanine series, solid concentration 100% (powder)] 0.65 parts by weight, near infrared absorber [Nippon Shokubai Co., Ltd., brand name "EX Color IR-910B", phthalocyanine series, solid content concentration 100% (powder)] After mixing 3.3 parts by weight, the total solid concentration was 30 It diluted with MIBK so that it might become amount% and prepared liquid A (coating liquid for hard coat layer formation).

The physical properties of the antireflective film thus produced are shown in Table 1. The transmittance | permeability in the whole area | region of wavelength 850-1000 nm of this antireflection film was 30% or less. In addition, the refractive index of the hard coat layer was 1.53.

Example 3

It carried out similarly to Example 1 except having changed the preparation of A liquid (coating liquid for hard coat layer formation) in Example 1 as follows.

<Preparation of A Amount>

2 parts by weight of a photopolymerization initiator [Shiba Specialty Chemicals, product name "Igacure 907"] to 100 parts by weight of a polyfunctional acrylate mixture (Arakawa Kagaku Co., Ltd., product name "Beamset 577CB", solid content concentration 100%). Part was added, and then a near-infrared absorber [Sumitomokinzoku Kozan Co., Ltd. product, brand name "YMF-01", cesium containing tungsten oxide (containing 33 mol% of cesium with respect to tungsten) content 10 weight% suspension, total solid concentration 14 weight %] 300 parts by weight was mixed, and further 5 parts by weight of silica particles [Tosoh Silica Co., Ltd., product name "Nipsil E-200", average particle diameter 3 µm) was added as an anti-glare imparting agent, and then the total solid A solution (coating solution for forming a hard coat layer) was prepared by diluting with MIBK such that the concentration was 30% by weight.

The physical properties of the antireflective film thus produced are shown in Table 1. The transmittance | permeability in the whole area | region of wavelength 850-1000 nm of this antireflection film was 30% or less. In addition, the refractive index of the hard coat layer was 1.53.

Comparative Example 1

In preparation of liquid A in Example 1 (1), it carried out similarly to Example 1 except not having used a near-infrared absorber, and produced the antireflection film. Refractive Index of the Hard Coating Layer: 1.53

The physical properties of the antireflective film thus produced are shown in Table 1.

Comparative Example 2

In the preparation of the liquid A of Example 1 (1), the coating liquid for forming a hard coat layer was the same as in Example 1 (1), except that the amount of the photopolymerization initiator "Igacure 907" was changed to 5 parts by weight. Was prepared.

Next, as a base film, the surface of PET film "A4300" (manufactured by Toyo Boseki Co., Ltd.) having a thickness of 100 µm was made to be 6 µm in thickness after curing of the coating liquid for forming the hard coating layer. Was applied. Next, after drying at 90 ° C. for 1 minute, ultraviolet rays were irradiated with a light quantity of 250 mJ / cm 2 to completely cure, thereby preparing a hard coat film.

The physical properties of the hard coat film thus produced are shown in Table 1.

Example Comparative example One 2 3 One 2 Haysuchi (%) 1.8 1.7 13.5 0.8 0.8 Total light transmittance (%) 77.4 50.5 75.1 95.2 91.2 60 ° gross - - 58 - - Spectral transmittance (%) 850 nm 14 10 14 90 14 900 nm 11 9 11 90 10 1000 nm 9 14 10 90 9 Reflectance (%) 500 nm 2.0 1.9 2.0 1.9 4.9 600 nm 1.7 1.6 1.7 1.7 4.9 700 nm 1.8 1.8 1.8 1.8 5.0 Scratch resistance ○ ○ ○ ○ ○

In Table 1, the antireflection films (Examples 1 to 3) of the present invention are all excellent in antireflection properties, and are also excellent in near infrared absorptivity and also excellent in scratch resistance. Moreover, since Example 3 contained the anti-glare imparting agent in the hard coat layer, the 60 degree gross | gloss value became 58.

On the other hand, Comparative Example 1 does not contain a near infrared absorber in the hard coat layer, so that the near infrared absorptive performance is not imparted. In Comparative Example 2, since the low refractive index layer was not formed, the antireflection property was poor.

The antireflection film of the present invention has near infrared absorption performance and antireflection performance, and is excellent in scratch resistance, and has a simple layer structure, which is low in cost, and is particularly suitable for PDP.

Claims (7)

On one side of the base film, a hard coating layer having a thickness of 2 to 20 µm containing (A) a curable resin by active energy ray irradiation and a near infrared absorber, and (B) a cured resin by active energy ray irradiation. A low refractive index layer having a refractive index of 1.43 or less and a thickness of 50 to 200 nm is sequentially laminated, and an antireflection film having a transmittance of 30% or less in the entire region of at least a wavelength of 850 to 1000 nm. According to claim 1, The near-infrared absorber in (A) layer is a tungsten oxide type compound, The antireflection film characterized by the above-mentioned. The method of claim 2, The tungsten oxide-based compound is cesium-containing tungsten oxide, antireflection film. The method according to any one of claims 1 to 3, The anti-reflection film comprising (A) the layer further comprising at least one filler selected from the group consisting of organic fillers and inorganic fillers. The method according to any one of claims 1 to 4, The antireflection film (B) layer contains 30 to 80 weight% of porous silica. The method according to any one of claims 1 to 5, The other surface of a base film has an adhesive layer of 5-50 micrometers in thickness, The antireflection film characterized by the above-mentioned. The method according to any one of claims 1 to 6, Anti-reflection film, characterized in that for plasma display.