JP2008151831A - Optical filter for display, display with the same and plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical filter for display which has light weight and thin thickness, is excellent in electromagnetic wave shielding property and is excellent in flatness, surface hardness and dimensional stability. <P>SOLUTION: The optical filter for display comprises: a mesh-like electric conductive layer and a hard coat layer disposed in the order on one side surface of a transparent film; and a near infrared ray absorbing layer disposed on the other side surface, wherein the surface of the hard coat layer has a surface roughness Ra less than 0.1 and a pencil hardness of 2H or more. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is applicable to various displays such as a plasma display panel (PDP), a cathode ray tube (CRT) display, a liquid crystal display, an organic EL (electroluminescent) display, and a field emission display (FED) including a surface electric field display (SED). The present invention relates to an optical filter having various functions such as antireflection, near-infrared shielding, electromagnetic wave shielding, and the like, and a display provided with this optical filter, particularly a PDP.

  In the case of flat panel displays such as liquid crystal displays, plasma displays (PDP), EL displays, and CRT displays, it has been known that the light from the outside is reflected on the surface and the internal visual information is difficult to see. Various measures have been taken, such as the installation of an optical film including an antireflection film.

  In recent years, large screen displays have become the mainstream of displays, and PDPs have become common as liquid crystal displays as large screen display devices. PDP has advantages such as faster response speed than liquid crystal display. However, in this PDP, high-frequency pulse discharge is performed on the light emitting part for image display, which may cause unnecessary electromagnetic wave radiation and infrared radiation which may cause malfunction of the infrared remote controller, etc. For this purpose, various PDP filters (electromagnetic wave shielding light transmitting window materials) having conductivity have been proposed for PDP. As the conductive layer of the electromagnetic wave shielding light transmitting window material, for example, (1) a transparent conductive thin film containing metallic silver, (2) a conductive mesh in which a metal wire or conductive fiber is made into a net, (3) on a transparent film Known are those in which a layer of copper foil or the like is etched into a net and an opening is provided, and (4) a conductive ink is printed in a mesh on a transparent film.

  Furthermore, in a large display such as a conventional PDP, a laminated film on which various films such as an antireflection film and a near infrared cut film are bonded is installed.

  In the above-mentioned electromagnetic shielding light-transmitting window material, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 11-74683), a transparent mesh is formed by interposing a conductive mesh between two transparent substrates such as glass plates. An electromagnetic wave shielding light transmission window material formed by joining and integrating with a resin is described.

  Patent Document 2 (Japanese Patent Laid-Open No. 2001-142406) discloses a laminate in which a single transparent substrate, an electromagnetic wave shielding material, an outermost antireflection film, and a near infrared cut film are laminated and integrated. The conductive adhesive tape is attached across the edge and front and back edges of the transparent substrate, and the conductive adhesive tape and the edge (end) of the electromagnetic shielding material are attached by the conductive adhesive. An electromagnetic wave shielding light-transmitting laminated film is described.

Japanese Patent Laid-Open No. 11-74683 JP 2001-142406 A

  As shown in Patent Document 1, a conventional display optical filter such as a PDP generally has a complicated manufacturing process because a plurality of functional films are manufactured and then bonded together, which is disadvantageous in terms of cost.

  For this reason, in order to improve productivity and reduce costs by reducing the number of parts, a PDP filter of a type that does not include glass in a filter member as shown in Patent Document 2 (straight tension type PDP filter) has been proposed. Yes. However, such direct stretch type PDP filters are similar to conventional filters in that they are bonded together after a functional film other than glass is manufactured in advance, and it cannot be said that the cost is sufficient. .

  In order to solve these problems, it is conceivable to employ a structure in which only one resin film is used as a substrate and a plurality of functional layers are formed on the surface thereof. The simplest manufacturing method is a method in which functional layers such as an antireflection layer and a near infrared absorption layer are formed by coating on an electromagnetic wave shielding film in which a conductive mesh is formed on a resin film.

However, when each functional layer is formed on the conductive mesh by coating as described above, that is, when each functional layer is formed on the conductive mesh by curing or the like, the function is affected by the unevenness of the mesh. It became clear that the flatness of the surface of the layer might not be sufficiently good. According to the study of the present inventor, when a relatively flexible film is formed as the functional layer, it has been found that good surface flatness is easily obtained, but the surface pencil hardness is insufficient.

  Accordingly, an object of the present invention is to provide an optical filter for a display which is light and thin, excellent in electromagnetic wave shielding properties, and excellent in flatness, surface hardness and dimensional stability.

  Another object of the present invention is to provide an optical filter for display which is light and thin, and has excellent flatness and surface hardness of a functional layer such as a hard coat layer or a near infrared absorption layer provided on a mesh-like conductive layer. To do.

  Furthermore, the present invention provides an optical filter suitable for a PDP that is lightweight and thin and has excellent flatness and hardness of a functional layer such as a hard coat layer or a near infrared absorption layer provided on a mesh-like conductive layer. Objective.

  Another object of the present invention is to provide a display in which the optical filter having the above excellent characteristics is bonded to the surface of an image display glass plate.

  Furthermore, an object of the present invention is to provide a PDP in which the optical filter having the excellent characteristics is bonded to the surface of an image display glass plate.

Therefore, the present invention
An optical filter for display comprising at least one transparent film, a mesh-like conductive layer provided thereon, and a functional layer provided on the mesh-like conductive layer,
An optical filter for display, wherein the surface of the functional layer has a surface roughness (Ra) of less than 0.2; and a mesh-like conductive layer and a hard coat layer provided in this order on one surface of the transparent film An optical filter for display comprising a near-infrared absorbing layer on the other surface,
An optical filter for display, wherein the surface of the hard coat layer has a surface roughness (Ra) of less than 0.2 and a pencil hardness of 2H or more;
It is in.

Preferred embodiments of the optical filter for display of the present invention are as follows.
(1) In the former display optical filter, the surface of the functional layer has a pencil hardness of 2H or more.
(2) In the former optical filter for display, the functional layer is a hard coat layer. Alternatively, another antireflection layer (eg, a low refractive index layer) may be used. A hard coat layer is preferred.
(3) The curing shrinkage of the functional layer such as the hard coat layer is in the range of 2 to 10%. It is easy to satisfy the surface roughness (Ra) and pencil hardness.
(4) The layer thickness of the mesh-like conductive layer is 1 to 10 μm, preferably 2 to 8 μm, particularly 3 to 6 μm. The functional layer or the hard coat layer can easily cover the concave portions of the mesh-like conductive layer.
(5) The mesh-like conductive layer is a layer including a metal vapor deposition film. A conductive layer by coating (eg, a coating layer in which conductive particles of an inorganic compound are dispersed in a polymer) may be used. Furthermore, the metal vapor deposition film or the electroconductive layer by coating, and the plating layer provided on it may be sufficient.
The mesh-like conductive layer is a conductive material layer made of a conductive material insoluble in a solvent on a film surface in which dots are formed on a transparent film surface by a substance soluble in a solvent such as water. The film layer is formed by a method (so-called printing mesh method) in which a coating layer or a vapor deposition layer of a conductive material is formed, and the film surface is removed using the above-mentioned solvent. Preferably, the present invention is advantageous.
(6) A low refractive index layer having a refractive index lower than that of the hard coat layer is formed on the hard coat layer. Good antireflection properties can be obtained.
(7) The transparent adhesive layer is provided in the near-infrared absorption layer on the surface on the opposite side to the transparent film. Mounting on the display becomes easy. The near infrared absorbing layer may have adhesiveness.
(8) The transparent film is a plastic film.
(9) A release sheet is provided on the transparent adhesive layer or the adhesive near-infrared absorbing layer. Mounting on the display becomes easy.
(10) A plasma display panel filter.

Further, the present invention is an optical filter for display comprising at least one transparent film, a mesh-like conductive layer provided thereon, and a functional layer provided on the mesh-like conductive layer,
An optical filter for display, wherein the functional layer has a curing shrinkage in the range of 2 to 10%; and a mesh-like conductive layer and a hard coat layer are provided in this order on one surface of the transparent film, and the other An optical filter for a display in which a near-infrared absorbing layer is provided on the surface of
There is also an optical filter for display characterized in that the curing shrinkage of the hard coat layer is in the range of 2 to 10%.

  The preferred embodiment of the optical filter can also be applied here.

Furthermore, the present invention provides:
A display characterized in that the optical filter for display is bonded to the surface of the image display glass plate; and a plasma characterized in that the optical filter for display is bonded to the surface of the image display glass plate It is also on the display panel.

  The optical filter for display according to the present invention is an optical filter having a simple structure in which a mesh-like conductive layer particularly excellent in electromagnetic wave shielding properties is provided and a functional layer such as a hard coat layer is directly provided thereon, and Excellent flatness, surface hardness and dimensional stability. In other words, since the surface of the mesh-like conductive layer is uneven, the functional layer such as the hard coat layer provided on the mesh-like conductive layer is affected by the unevenness to achieve both a high level of surface flatness and surface hardness. Although it is difficult to make this happen, in the present invention, this can be achieved by controlling the curing shrinkage rate of the functional layer.

  Therefore, the optical filter for display of the present invention is light and thin, excellent in electromagnetic shielding properties, excellent in flatness and surface hardness, and thus excellent in dimensional stability.

  In addition, providing a functional layer such as a hard coat layer directly on the mesh-like conductive layer as described above is effective for reducing the thickness of the optical filter itself. For example, the optical filter is obtained using one transparent film. In this case, the thickness of the optical filter becomes extremely small, and the mass of the optical filter decreases accordingly. Therefore, it is very advantageous in handling when the display is mounted on the display and after mounting.

  Therefore, the optical filter for display of the present invention includes a field emission display (FED) including a plasma display panel (PDP), a cathode ray tube (CRT) display, a liquid crystal display, an organic EL (electroluminescence) display, and a surface electric field display (SED). It can be said that the optical filter has various functions such as anti-reflection, near-infrared shielding, and electromagnetic wave shielding for various displays such as).

  The display optical filter excellent in surface flatness and hardness of the present invention will be described in detail below.

  FIG. 1 shows a schematic sectional view of an example showing the basic structure of the optical filter for display of the present invention. In FIG. 1, an antireflection layer 17 such as a mesh-like conductive layer 13, a hard coat layer 16 and a low refractive index layer is provided in this order on one surface of a transparent film 12, and a near-infrared absorbing layer is provided on the other surface. 14 and the transparent adhesive layer 15 are provided thereon. In this configuration, the antireflection property is slightly inferior, but the antireflection layer 17 may be omitted. Moreover, although it is inferior to near-infrared shielding, the near-infrared absorption layer 14 and the transparent adhesive layer 15 on it may not be present. The functional layer may be an antireflection layer other than the hard coat layer 16, such as a low refractive index layer.

  The concave portion of the mesh conductive layer 13 is completely covered with the hard coat layer 16, and the mesh conductive layer 13 is not exposed. And the hard-coat layer 16 which is a functional layer of this invention has the outstanding flatness and high pencil hardness. That is, the hard coat layer 16 has a surface roughness (Ra) of less than 0.2 (particularly less than 0.1) and a pencil hardness of 2H or more.

  The surface roughness (Ra) is determined by measuring the center line average roughness (Ra) of the hard coat layer using a contact-type surface roughness meter (Talystep; manufactured by Taylor Hopson Co., Ltd.). The pencil hardness is measured according to JIS-K-5600 (2002).

  The mesh conductive layers 13 and 23 are, for example, mesh-shaped metal layers or metal-containing layers. The mesh-like metal layer or metal-containing layer is generally formed by etching or printing. This makes it easy to obtain low resistance. In general, the concave portions (voids) of the mesh-shaped metal layer or the mesh of the metal-containing layer are completely filled with the functional layer as shown in FIG. This improves transparency.

  The mesh conductive layer of the present invention is preferably a thin layer formed by a so-called printing mesh method, which is formed by a printing method. The mesh conductive layer is generally a metal vapor-deposited film, but may be a conductive layer by coating (for example, a coating layer in which conductive particles of an inorganic compound are dispersed in a polymer). Furthermore, the metal vapor deposition film or the electroconductive layer by coating, and the plating layer provided on it may be sufficient.

  The thickness of the mesh-like conductive layer is generally 1 to 10 μm, preferably 2 to 8 μm, particularly preferably 3 to 6 μm. Such a mesh-like conductive layer can enlarge an opening, and can brighten the screen of the display. In addition, a functional layer such as a hard coat layer is advantageous for easily covering the concave portions of the mesh-like conductive layer easily.

  The antireflection layer 17 is generally a low refractive index layer. That is, the antireflection effect is exhibited by the composite film of the hard coat layer 16 and the low refractive index layer provided thereon. A high refractive index layer may be provided between the low refractive index layer and the hard coat layer 16. This improves the antireflection function.

  Further, the antireflection layer 17 may not be provided, and only the transparent film and the hard coat layer 16 having a refractive index higher or lower (preferably lower) than that of the transparent film may be used. The hard coat layer 16 and the antireflection layer 17 are preferably formed by coating from the viewpoints of productivity and economy.

  The near-infrared absorbing layer 14 has a function of blocking unnecessary light such as neon light emission of PDF. In general, it is a layer containing a dye having an absorption maximum at 800 to 1200 nm. The transparent adhesive layer 15 is generally provided for easy mounting on a display. A release sheet may be provided on the transparent adhesive layer 15.

  The above-described optical filter for display is formed, for example, by forming a mesh-like conductive layer, a hard coat layer, and an antireflection layer on one surface of a long plastic film, and a near-infrared absorbing layer, a transparent adhesive on the other surface. It is obtained by forming a layer and cutting it into a rectangular shape.

  In the case of a rectangular transparent film, each layer may be formed in a batch system. However, as described above, it is preferable to form each layer on a continuous film, in a roll-to-roll system, and to cut the layers.

  The materials used for the optical filter for display of the present invention will be described in detail below.

  The material of the transparent film is not particularly limited as long as it is transparent (meaning “transparent to visible light”), but a plastic film is generally used. For example, polyester {eg, polyethylene terephthalate (PET), polybutylene terephthalate}, polymethyl methacrylate (PMMA), acrylic resin, polycarbonate (PC), polystyrene, triacetate resin, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyethylene, Examples thereof include ethylene-vinyl acetate copolymer, polyvinyl butyral, metal ion crosslinked ethylene-methacrylic acid copolymer, polyurethane, cellophane and the like. Among these, polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), etc. are highly resistant to loads during processing (heat, solvent, bending, etc.) and particularly highly transparent. preferable. In particular, PET is preferable because it has excellent processability.

  The thickness of the transparent film varies depending on the use of the optical filter, but is generally 1 μm to 10 mm, 1 μm to 5 mm, and particularly preferably 25 to 250 μm.

  The conductive layer of the present invention is set so that the surface resistance value of the obtained optical filter is generally 10Ω / □ or less, preferably 0.001 to 5Ω / □, particularly 0.005 to 5Ω / □. Is done.

  As a mesh-like conductive layer, in addition to those formed by the above-mentioned printing mesh method, a layer of copper foil or the like on a transparent film is etched into a net-like shape, an opening is provided, and a conductive ink is applied on the transparent film. The thing printed on the mesh form etc. can be mentioned.

  In the case of a mesh-like conductive layer, the mesh preferably has a wire diameter of 1 μm to 1 mm and an aperture ratio of 40 to 95%. A more preferable wire diameter is 10 to 500 μm, and an aperture ratio is 50 to 95%. When the wire diameter exceeds 1 mm in the mesh-like conductive layer, the electromagnetic wave shielding property is improved, but the aperture ratio is lowered and cannot be made compatible. If it is less than 1 μm, the strength as a mesh is lowered and handling becomes difficult. Further, when the aperture ratio exceeds 95%, it is difficult to maintain the shape as a mesh. When the aperture ratio is less than 40%, the light transmittance is reduced, and the amount of light from the display is also reduced.

  The opening ratio of the conductive mesh refers to the area ratio occupied by the opening portion in the projected area of the conductive mesh.

  When a conductive foil such as a metal foil is subjected to pattern etching, copper, stainless steel, aluminum, nickel, iron, brass, or an alloy thereof, preferably copper, stainless steel, or aluminum is used as the metal of the metal foil.

  If the thickness of the metal foil is too thin, it is not preferable in terms of handleability and workability of pattern etching, and if it is too thick, it affects the thickness of the film obtained, and the time required for the etching process becomes long. The thickness is preferably about 1 to 200 μm.

  The shape of the etching pattern is not particularly limited, and examples thereof include a grid-like metal foil in which square holes are formed, and a punching metal-like metal foil in which circular, hexagonal, triangular or elliptical holes are formed. It is done. Further, the holes are not limited to those regularly arranged, and may be a random pattern. It is preferable that the area ratio of the opening part in the projection surface of this metal foil is 20 to 95%.

  Alternatively, the mesh-like conductive layer may be formed by pattern printing of conductive ink on a transparent substrate. Using the following conductive ink, it can be printed on the surface of the transparent substrate by screen printing, ink jet printing, electrostatic printing or the like.

  In general, carbon black particles having a particle size of 100 μm or less, or particles of a conductive material such as particles of metals or alloys such as copper, aluminum, nickel, etc. are bound to a binder of PMMA, polyvinyl acetate, epoxy resin or the like at a concentration of 50 to 90% by weight. Dispersed in resin. This ink is diluted or dispersed at a suitable concentration in a solvent such as toluene, xylene, methylene chloride, water, etc., applied to the surface of the transparent substrate by printing, and then dried at room temperature to 120 ° C. as necessary. Apply. Particles obtained by covering the same conductive material particles as described above with a binder resin are directly applied by electrostatic printing and fixed by heat or the like.

  The thickness of the printed film formed in this way is not preferable because the electromagnetic wave shielding property is insufficient if it is too thin, and if it is too thick, it affects the thickness of the resulting film, so it is about 0.5 to 100 μm. It is preferable to do this.

  According to such pattern printing, the degree of freedom of the pattern is large, and a conductive layer having an arbitrary wire diameter, interval and opening shape can be formed. Therefore, a plastic film having desired electromagnetic wave shielding properties and light transmission properties Can be easily formed.

  There is no particular limitation on the pattern printing shape of the conductive layer. For example, a grid-like printed film having a rectangular opening or a punching metal shape having a circular, hexagonal, triangular or elliptical opening. Examples include printed films. Further, the openings are not limited to those regularly arranged, and may be a random pattern. It is preferable that the area ratio of the opening part in the projection surface of this printed film is 20 to 95%.

  In the present invention, the mesh-like conductive layer is preferably formed by the printing mesh method as described above.

  About the said printing mesh method, the schematic explaining the formation method of the conductive layer in FIG. 2 is shown. First, as shown in (1) and (2), dots 2 are printed on the transparent substrate 1 using a material soluble in a solvent such as water. Next, as shown in (3), the conductive material layer 3 is formed so as to cover all of the transparent substrate exposed surface above and between the dots 2 of the transparent substrate 1. The conductive material layer 3 is also provided on the dots, but if it is too thick, the dots cannot be removed by subsequent cleaning. Next, the transparent substrate 1 is washed with a solvent such as water. At this time, if necessary, dissolution accelerating means such as ultrasonic irradiation, rubbing with a brush, sponge or the like may be used in combination. The conductive material layer 3 is also preferably formed by vapor deposition of metal because low resistance is easily obtained.

  By the above washing, the soluble dots 2 are dissolved as shown in (4), and the conductive material on the dots 2 is also peeled off from the transparent substrate 1 and removed. Then, a conductive pattern (mesh-like conductive layer) 4 made of a conductive material formed in a region between the dots remains on the transparent substrate 1. Since this conductive pattern 4 occupies the area between the dots 1, it has a mesh shape (lattice shape) as a whole.

  Accordingly, by making the gap between the dots 2 narrow, a grid-like conductive pattern 4 having a small line width is formed. Further, by increasing the area of each dot 2, a mesh-like conductive pattern 4 having a large aperture ratio is formed. The printing material soluble in water or the like for forming the dots 2 does not require fine particles to be dispersed, and even a low viscosity material can be used sufficiently. By using this low-viscosity printing material, dots can be printed so as to have a fine dot pattern.

  In addition, after the step (4), the conductive layer for the electromagnetic wave shielding light-transmitting window material is obtained by performing final cleaning (rinsing) and drying as necessary.

  Examples of the conductive layer formed by coating in the printing mesh method include a coating layer in which conductive particles of an inorganic compound are dispersed in a polymer.

  Examples of the inorganic compound constituting the conductive particles include metals, alloys such as aluminum, nickel, indium, chromium, gold, vanadium, tin, cadmium, silver, platinum, copper, titanium, cobalt, lead; or ITO, oxidation Indium, tin oxide, zinc oxide, indium oxide-tin oxide (ITO, so-called indium-doped tin oxide), tin oxide-antimony oxide (ATO, so-called antimony-doped tin oxide), zinc oxide-aluminum oxide (ZAO; so-called aluminum-doped oxide) And conductive oxides such as zinc). In particular, ITO is preferable. The average particle size is preferably 10 to 10,000 nm, particularly preferably 10 to 50 nm.

  Examples of the polymer include acrylic resin, polyester resin, epoxy resin, urethane resin, phenol resin, maleic acid resin, melamine resin, urea resin, polyimide resin, and silicon-containing resin. Furthermore, it is preferable that it is a thermosetting resin among these resins.

  The conductive layer is formed by coating by dispersing the conductive fine particles in a polymer (using a solvent if necessary) by mixing or the like to prepare a coating solution, and coating the coating solution on a transparent substrate. And then drying and curing as appropriate. In the case of using a thermoplastic resin, it is obtained by drying after coating, and in the case of a thermosetting type, it is obtained by drying and thermosetting. When an ultraviolet curable resin is used, it can be obtained by drying after application and irradiating with ultraviolet rays after coating.

  The thickness of the conductive layer formed by coating is preferably 0.01 to 5 μm, particularly preferably 0.05 to 3 μm. When the thickness is less than 0.01 μm, the electromagnetic wave shielding property may not be sufficient. On the other hand, when the thickness exceeds 5 μm, the transparency of the resulting film may be lowered.

  In the printing mesh method shown in FIG. 2, when the conductive layer is formed by a vapor deposition method (metal vapor deposition film), the formation method is not particularly limited, but sputtering, ion plating, electron beam Vapor deposition methods such as vapor deposition, vacuum deposition, chemical vapor deposition, printing, coating, etc. can be mentioned. Vapor deposition methods (sputtering, ion plating, electron beam vapor deposition, vacuum vapor deposition, chemical vapor deposition) Is preferred. A conductive layer can be formed using an inorganic compound constituting the conductive particles. When the conductive layer is formed by a vapor deposition method, the layer thickness is preferably 0.1 to 10 μm, more preferably 2 to 8 μm, and particularly preferably 3 to 6 μm.

  A metal plating layer may be further provided on the conductive layer in order to improve conductivity. The metal plating layer can be formed by a known electrolytic plating method or electroless plating method. As the metal used for plating, generally, copper, copper alloy, nickel, aluminum, silver, gold, zinc or tin can be used, preferably copper, copper alloy, silver or nickel, In particular, it is preferable to use copper or a copper alloy from the viewpoint of economy and conductivity.

  Moreover, you may give anti-glare performance. When this anti-glare treatment is performed, a blackening treatment may be performed on the surface of the (mesh) conductive layer. For example, oxidation treatment of a metal film, black plating such as chromium alloy, application of black or dark ink, and the like can be performed.

  The antireflection layer of the present invention is generally a composite film of a hard coat layer and a low refractive index layer provided thereon, or a high refractive index layer is further provided between the hard coat layer and the low refractive index layer. It is a composite membrane provided. Even if the antireflection layer is only a hard coat layer having a refractive index lower than that of the substrate, it is effective. However, when the refractive index of the substrate is low, a composite film of a hard coat layer having a higher refractive index than the transparent film and a low refractive index layer provided thereon, or a higher refractive index layer is provided on the low refractive index layer. A composite film obtained may be used.

  As a hard-coat layer, an acrylic resin layer, an epoxy resin layer, a urethane resin layer, a silicone resin layer, etc. can be mentioned, The thickness is 1-50 micrometers normally, Preferably it is 1-10 micrometers. Either a thermosetting resin or an ultraviolet curable resin may be used, but an ultraviolet curable resin is preferable.

  Examples of the thermosetting resin include phenol resin, resorcinol resin, urea resin, melamine resin, epoxy resin, acrylic resin, urethane resin, furan resin, and silicon resin.

  Examples of the ultraviolet curable resin (monomer, oligomer) include 2-hydroxyethyl (meth) acrylate [(meth) acrylate means acrylate and methacrylate], 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl. (Meth) acrylate, 2-ethylhexyl polyethoxy (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, phenyloxyethyl (meth) acrylate, tricyclodecane mono (meth) acrylate, dicyclopentenyloxyethyl ( (Meth) acrylate, tetrahydrofurfuryl (meth) acrylate, acryloylmorpholine, N-vinylcaprolactam, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, o Phenylphenyloxyethyl (meth) acrylate, neopentyl glycol di (meth) acrylate, neopentyl glycol dipropoxy di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, tricyclodecane dimethylol di (meth) Acrylate, 1,6-hexanediol di (meth) acrylate, nonanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tris [( (Meth) acryloxyethyl] isocyanurate, (meth) acrylate monomers such as ditrimethylolpropane tetra (meth) acrylate; polyol compounds (for example, Ethylene glycol, propylene glycol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-ethyl-2-butyl-1,3-propanediol, Polyols such as trimethylolpropane, diethylene glycol, dipropylene glycol, polypropylene glycol, 1,4-dimethylolcyclohexane, bisphenol A polyethoxydiol, polytetramethylene glycol, the polyols and succinic acid, maleic acid, itaconic acid, adipine Polyester polyols that are a reaction product of acid, hydrogenated dimer acid, phthalic acid, isophthalic acid, terephthalic acid and the like, or these acid anhydrides, and a reaction product of the polyols and ε-caprolactone. Po Caprolactone polyols, reaction products of the above polyols with the above-mentioned polybasic acids or ε-caprolactone of these acid anhydrides, polycarbonate polyols, polymer polyols, etc.) and organic polyisocyanates (for example, tolylene diisocyanate, isophorone diisocyanate, Xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, dicyclopentanyl diisocyanate, hexamethylene diisocyanate, 2,4,4'-trimethylhexamethylene diisocyanate, 2,2'-4-trimethylhexamethylene diisocyanate) and hydroxyl groups Containing (meth) acrylate (for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate Chryrate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, cyclohexane-1,4-dimethylol mono (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, glycerin di (meth) acrylate, etc.) reaction product of polyurethane (meth) acrylate, bisphenol A type epoxy resin, bisphenol F type epoxy resin, etc. and (meth) acrylic acid And (meth) acrylate oligomers such as bisphenol-type epoxy (meth) acrylate. These compounds can be used alone or in combination. These ultraviolet curable resins may be used as a thermosetting resin together with a thermal polymerization initiator.

  Any compound suitable for the properties of the ultraviolet curable resin can be used as the photopolymerization initiator for the ultraviolet curable resin. For example, acetophenone such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1 Benzoin series such as benzyl dimethyl ketal, benzophenone, 4-phenylbenzophenone, benzophenone series such as hydroxybenzophenone, thioxanthone series such as isopropylthioxanthone, 2-4-diethylthioxanthone, and other special types include methylphenyl glyoxylate Etc. can be used. Particularly preferably, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropane-1, Examples include benzophenone. These photopolymerization initiators may be optionally selected from one or more known photopolymerization accelerators such as benzoic acid type or tertiary amine type such as 4-dimethylaminobenzoic acid. It can be used by mixing at a ratio. Moreover, it can be used by 1 type, or 2 or more types of mixture of only a photoinitiator. Particularly preferred is 1-hydroxycyclohexyl phenyl ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals).

  The quantity of a photoinitiator is 0.1-10 mass% with respect to a resin composition, Preferably it is 0.1-5 mass%.

  The hard coat layer preferably has a refractive index lower than that of the transparent film. By using the ultraviolet curable resin, a refractive index lower than that of the substrate is generally easily obtained. Therefore, it is preferable to use a material having a high refractive index such as PET as the transparent substrate. Therefore, the hard coat layer preferably has a refractive index of 1.60 or less. The film thickness is as described above.

  For the hard coat layer, among the above UV curable resins (monomer, oligomer), pentaerythritol tri (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane Hard polyfunctional monomers such as tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tris [(meth) acryloxyethyl] isocyanurate, ditrimethylolpropane tetra (meth) acrylate It is preferable to use mainly.

In the present invention, when a hard coat layer is provided as a functional layer on a mesh-like conductive layer, a surface roughness (Ra) of less than 0.2 (particularly less than 0.1) and a pencil of 2H or more as described above. It is preferable to have hardness. For this purpose, it is generally preferred that the curing shrinkage of the hard coat layer is in the range of 2 to 10%. The cure shrinkage rate is
[{(Specific gravity before curing) − (specific gravity before curing)} / {specific gravity before curing}] × 100
Is obtained.

  The hard coat layer having such a curing shrinkage rate is pentaerythritol polyfunctional (meth) acrylate such as pentaerythritol tri (meth) acrylate, pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like. Combinations with other monomers or oligomers are preferred. Other monomers or oligomers include neopentyl glycol di (meth) acrylate, neopentyl glycol dipropoxy di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, and tricyclodecane dimethylol di (meth) acrylate. , 1,6-hexanediol di (meth) acrylate, nonanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipropylene glycol (meth) acrylate, tripropylene glycol (meth) acrylate, etc. Trifunctional (meth) acrylate monomers; and bisphenol type epoxy resins such as polyurethane (meth) acrylate, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and the like; (Meth) acrylate oligomers such as bisphenol type epoxy (meth) acrylate, which is a reaction product of (meth) acrylic acid, and bisphenol type epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin and (meth) ) A (meth) acrylate oligomer such as bisphenol-type epoxy (meth) acrylate, which is a reaction product of acrylic acid, is preferred.

  In particular, a combination of the above pentaerythritol polyfunctional (meth) acrylate and a bisphenol-type epoxy (meth) acrylate is preferable, and the former: the latter is preferably 90:10 to 10:90, and particularly preferably 90:10 to 20:80.

  Alternatively, in order to obtain a hard coat layer having the specific surface roughness (Ra) and pencil hardness, a polymethyl propane skeleton such as trimethylolpropane tri (meth) acrylate and ditrimethylolpropane tetra (meth) acrylate is used. It is also preferable to use functional (meth) acrylate monomers as the main component (generally 90% by mass or more, particularly 95% by mass or more).

  The hard coat layer may contain fillers such as metal fine particles used in a high refractive index layer, which will be described later, and fine particles used in a low refractive index.

The high refractive index layer is made of ITO, ATO, Sb ₂ O ₅ , Sb ₂ O ₃ , SbO ₂ , In ₂ O ₃ , SnO ₂ , ZnO, ZrO ₂ , Al in a polymer (preferably UV curable resin). A layer in which conductive metal oxide fine particles (inorganic compounds) such as doped ZnO and TiO ₂ are dispersed is preferable. The metal oxide fine particles preferably have an average particle size of 10 to 10,000 nm, preferably 10 to 50 nm. In particular, ITO (especially having an average particle diameter of 10 to 50 nm) and SnO ₂ —ZrO ₂ —Sb ₂ O ₅ —SiO ₂ mixture (eg, trade name Sun Colloid HX-305M5, manufactured by Nissan Chemical Industries, Ltd.) are preferred. Those having a refractive index of 1.64 or more are suitable. The film thickness is generally in the range of 10 to 500 nm, preferably 20 to 200 nm.

  When the high refractive index layer is a conductive layer, the minimum reflectance of the surface reflectance of the antireflection film should be within 1.5% by setting the refractive index of the high refractive index layer to 1.64 or more. The minimum reflectance of the surface reflectance of the antireflection film can be made to be within 1.0% by setting it to 1.69 or more, preferably 1.69 to 1.82.

  The low refractive index layer is a layer (cured) in which fine particles such as silica and fluororesin, preferably hollow silica, are dispersed in a polymer (preferably UV curable resin) in an amount of 10 to 60% by weight (preferably 10 to 50% by weight). Layer). The refractive index of this low refractive index layer is preferably 1.40 to 1.51. When the refractive index is more than 1.51, the antireflection property of the antireflection film is deteriorated. The film thickness is generally in the range of 10 to 500 nm, preferably 20 to 200 nm.

  As the hollow silica, those having an average particle diameter of 10 to 100 nm, preferably 10 to 50 nm, and a specific gravity of 0.5 to 1.0, preferably 0.8 to 0.9 are preferable.

  The hard coat layer preferably has a visible light transmittance of 85% or more. Both the visible light transmittance of the high refractive index layer and the low refractive index layer are preferably 85% or more.

  When the antireflection layer is composed of the above three layers, for example, the thickness of the hard coat layer is 2 to 20 μm, the thickness of the high refractive index layer is 75 to 200 nm, and the thickness of the low refractive index layer is 75 to 200 nm. Preferably there is. Further, the total visible light transmittance of such three layers is also preferably 85% or more.

  When the low refractive index layer is a functional layer, the specified surface roughness and pencil hardness can be obtained by determining the composition of the low refractive index layer based on the composition of the hard coat layer.

  In order to form each layer of the antireflection layer including the hard coat layer, as described above, the above-mentioned fine particles are blended with a polymer (preferably an ultraviolet curable resin) as necessary, and the obtained coating liquid is applied. Then, it is dried and, if necessary, cured by heat, or after coating, if necessary, dried and irradiated with ultraviolet rays. In this case, each layer may be applied and cured one by one, or all the layers may be applied and then cured together.

  As a specific method of coating, a method of coating a coating solution in which an ultraviolet curable resin containing an acrylic monomer or the like is made into a solution with a solvent such as toluene is coated with a gravure coater, and then dried, and then cured by ultraviolet rays. Can be mentioned. This wet coating method has the advantage that the film can be uniformly formed at high speed at low cost. After this coating, for example, by irradiating and curing with ultraviolet rays, the effect of improving the adhesion and increasing the hardness of the film can be obtained. The conductive layer can be formed similarly.

  In the case of ultraviolet curing, many light sources that emit light in the ultraviolet to visible range can be used as the light source, such as ultra-high pressure, high pressure, low pressure mercury lamp, chemical lamp, xenon lamp, halogen lamp, mercury lamp, carbon arc lamp, incandescent lamp. And laser light. The irradiation time cannot be determined unconditionally depending on the type of lamp and the intensity of the light source, but is about several seconds to several minutes. Moreover, in order to accelerate curing, the laminate may be preheated to 40 to 120 ° C. and irradiated with ultraviolet rays.

  The antireflection layer of the present invention is preferably formed by coating as described above, but may be formed by a vapor phase film forming method. Usually, the high refractive index layer and the low refractive index layer can be formed by physical vapor deposition or chemical vapor deposition. Examples of the physical vapor deposition method include a vacuum vapor deposition method, a sputtering method, an ion plating method, and a laser ablation method, but it is generally preferable to form a film by the sputtering method. Examples of the chemical vapor deposition method include an atmospheric pressure CVD method, a low pressure CVD method, and a plasma CVD method.

  Examples of the combination of the high refractive index layer and the low refractive index layer include the following.

(A) 1 layer each in the order of high refractive index layer / low refractive index layer, laminated in a total of 2 layers, (b) 2 layers of high refractive index layer / low refractive index layer alternately, 4 layers in total (C) One layer each in the order of medium refractive index layer / high refractive index layer / low refractive index layer, laminated in a total of three layers, (d) high refractive index layer / low refractive index layer In this order, each layer is alternately stacked in 3 layers for a total of 6 layers. As the high refractive index layer, ITO (tin indium oxide) or ZnO, a thin film of ZnO, TiO ₂ , SnO ₂ , ZrO or the like doped with Al can be employed. As the low refractive index layer, a thin film having a refractive index of 1.6 or less, such as SiO ₂ , MgF ₂ , Al ₂ O _3, or the like can be used.

  The high refractive index layer, the low refractive index layer, and the like can be formed by physical vapor deposition or chemical vapor deposition. Examples of the physical vapor deposition method include a vacuum vapor deposition method, a sputtering method, an ion plating method, and a laser ablation method, but it is generally preferable to form a film by the sputtering method. Examples of the chemical vapor deposition method include an atmospheric pressure CVD method, a low pressure CVD method, and a plasma CVD method.

  A near-infrared absorption layer is generally obtained by forming a layer containing a pigment or the like on the surface of a transparent film. A near-infrared absorption layer is obtained by, for example, applying a coating liquid containing a pigment and a binder resin or an ultraviolet curable or electron beam curable resin, and if necessary, drying and curing. When used as a film, it is generally a near-infrared cut film, such as a film containing a pigment or the like. The dye generally has an absorption maximum at a wavelength of 800 to 1200 nm. Examples include phthalocyanine dyes, metal complex dyes, nickel dithiolene complex dyes, cyanine dyes, squarylium dyes, polymethine dyes, Examples thereof include azomethine dyes, azo dyes, polyazo dyes, diimonium dyes, aminium dyes, and anthraquinone dyes, and cyanine dyes or squarylium dyes are particularly preferable. These dyes can be used alone or in combination. Examples of the binder resin include thermoplastic resins such as acrylic resins.

  In the present invention, the near-infrared absorbing layer may be provided with a function of adjusting color tone by providing a function of absorbing neon light emission. For this purpose, a neon-emission absorption layer may be provided, but a neon-emission selective absorption dye may be included in the near-infrared absorption layer.

  Examples of selective absorption dyes for neon emission include cyanine dyes, squarylium dyes, anthraquinone dyes, phthalocyanine dyes, polymethine dyes, polyazo dyes, azurenium dyes, diphenylmethane dyes, and triphenylmethane dyes. it can. Such a selective absorption dye is required to have a selective absorption of neon emission near 585 nm and a small absorption at other visible light wavelengths, so that the absorption maximum wavelength is 575 to 595 nm and the absorption spectrum half width is What is 40 nm or less is preferable.

  Also, when combining multiple types of near-infrared or neon luminescent absorbing dyes, if there is a problem with the solubility of the dye, if there is a reaction between the dyes due to mixing, if there is a decline in heat resistance, moisture resistance, etc. All the near-infrared absorbing dyes need not be contained in the same layer, and may be contained in another layer.

  Further, as long as the optical properties are not greatly affected, coloring pigments, ultraviolet absorbers, antioxidants and the like may be further added.

  As a near-infrared absorption characteristic of the optical filter of the present invention, it is preferable that the transmittance at 850 to 1000 nm is 20% or less, and further 15%. Moreover, as selective absorptivity, it is preferable that the transmittance | permeability of 585 nm is 50% or less. Especially in the former case, there is an effect of reducing the transmittance in a wavelength region where malfunction of a remote controller of a peripheral device is pointed out. In the latter case, an orange color having a peak at 575 to 595 nm is color reproducibility. This has the effect of absorbing the orange wavelength, thereby improving the redness and improving the color reproducibility.

  The layer thickness of the near infrared absorbing layer is generally 0.5 to 50 μm.

  The transparent adhesive layer of the present invention is a layer for adhering the optical film of the present invention to a display, and any resin can be used as long as it has an adhesive function. For example, acrylic adhesives, rubber adhesives, SEBS (styrene / ethylene / butylene / styrene) and SBS (styrene / butadiene / styrene) and other thermoplastic elastomers (TPE) as main components TPE-based pressure-sensitive adhesives and adhesives can also be used.

  The layer thickness is generally in the range of 5 to 500 μm, particularly 10 to 100 μm. In general, the optical filter can be equipped by heat-pressing the pressure-sensitive adhesive layer to a glass plate of a display.

  When two transparent films are used in the present invention, for example, ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, acrylic resin (eg, ethylene- (meth) acrylic acid copolymer) Polymer, ethylene- (meth) ethyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, metal ion crosslinked ethylene- (meth) acrylic acid copolymer), partially saponified ethylene-vinyl acetate copolymer Examples thereof include ethylene copolymers such as a polymer, a carboxylated ethylene-vinyl acetate copolymer, an ethylene- (meth) acryl-maleic anhydride copolymer, and an ethylene-vinyl acetate- (meth) acrylate copolymer. ("(Meth) acryl" means "acryl or methacryl"). In addition, polyvinyl butyral (PVB) resin, epoxy resin, phenol resin, silicon resin, polyester resin, urethane resin, rubber adhesive, thermoplastic elastomers such as SEBS and SBS can be used, but good adhesion Acrylic resin adhesives and epoxy resins are easily obtained.

  The layer thickness is generally 10 to 50 μm, preferably 20 to 30 μm. In general, the optical filter can be equipped by heat-pressing the pressure-sensitive adhesive layer to a glass plate of a display.

  When EVA is also used as the material for the transparent adhesive layer, the EVA has a vinyl acetate content of 5 to 50% by weight, preferably 15 to 40% by weight. When the vinyl acetate content is less than 5% by weight, there is a problem in transparency, and when it exceeds 40% by weight, the mechanical properties are remarkably deteriorated and the film formation becomes difficult and the films are easily blocked.

  As the cross-linking agent, an organic peroxide is suitable for heat cross-linking and is selected in consideration of sheet processing temperature, cross-linking temperature, storage stability, and the like. Examples of peroxides that can be used include 2,5-dimethylhexane-2,5-dihydroperoxide; 2,5-dimethyl-2,5-di (t-butylperoxy) hexane-3; -Butyl peroxide; t-butylcumyl peroxide; 2,5-dimethyl-2,5-di (t-butylperoxy) hexane; dicumyl peroxide; α, α'-bis (t-butylperoxyisopropyl) ) Benzene; n-butyl-4,4-bis (t-butylperoxy) valerate; 2,2-bis (t-butylperoxy) butane; 1,1-bis (t-butylperoxy) cyclohexane; , 1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane; t-butylperoxybenzoate; benzoyl peroxide; Luperoxyacetate; 2,5-dimethyl-2,5-bis (tertiarybutylperoxy) hexyne-3; 1,1-bis (tertiarybutylperoxy) -3,3,5-trimethylcyclohexane; 1-bis (tert-butylperoxy) cyclohexane; methyl ethyl ketone peroxide; 2,5-dimethylhexyl-2,5-bisperoxybenzoate; tert-butyl hydroperoxide; p-menthane hydroperoxide; p-chlorobenzoyl Peroxides; tertiary butyl peroxyisobutyrate; hydroxyheptyl peroxide; chlorohexanone peroxide. These peroxides are used singly or in combination of two or more, and are usually used at a ratio of 5 parts by mass or less, preferably 0.5 to 5.0 parts by mass with respect to 100 parts by weight of EVA. .

  The organic peroxide is usually kneaded with EVA using an extruder, a roll mill or the like, but may be dissolved in an organic solvent, a plasticizer, a vinyl monomer or the like and added to the EVA film by an impregnation method.

  Various acryloxy group or methacryloxy group and allyl group-containing compounds can be added to improve EVA physical properties (mechanical strength, optical properties, adhesiveness, weather resistance, whitening resistance, crosslinking speed, etc.). . As the compound used for this purpose, acrylic acid or methacrylic acid derivatives, for example, esters and amides thereof are the most common. As the ester residue, in addition to alkyl groups such as methyl, ethyl, dodecyl, stearyl, lauryl, cyclohexyl groups , Tetrahydrofurfuryl group, aminoethyl group, 2-hydroxyethyl group, 3-hydroxypropyl group, 3-chloro-2-hydroxypropyl group and the like. Further, esters with polyfunctional alcohols such as ethylene glycol, triethylene glycol, polyethylene glycol, trimethylolpropane, and pentaerythritol can also be used. A typical amide is diacetone acrylamide.

  Examples thereof include polyfunctional esters such as acrylic or methacrylic acid esters such as trimethylolpropane, pentaerythritol, glycerin, triallyl cyanurate, triallyl isocyanurate, diallyl phthalate, diallyl isophthalate, diallyl maleate, etc. Examples include allyl group-containing compounds. These are used alone or in combination of two or more, and are usually used in an amount of 0.1 to 2 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of EVA. .

  When EVA is crosslinked by light, a photosensitizer is usually used in an amount of 5 parts by mass or less, preferably 0.1 to 3.0 parts by mass based on 100 parts by mass of EVA instead of the peroxide.

  In this case, usable photosensitizers include, for example, benzoin, benzophenone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, dibenzyl, 5-nitroacenaphthene, hexachlorocyclopentadiene, p-nitrodiphenyl. , P-nitroaniline, 2,4,6-trinitroaniline, 1,2-benzanthraquinone, 3-methyl-1,3-diaza-1,9-benzanthrone, and the like. Alternatively, two or more types can be mixed and used.

  Moreover, a silane coupling agent is used in combination as an adhesion promoter. As this silane coupling agent, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycid Xylpropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-chloropropylmethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- β (aminoethyl) -γ-aminopropyltrimethoxysilane and the like can be mentioned.

  The silane coupling agent is generally used in an amount of 0.001 to 10 parts by mass, preferably 0.001 to 5 parts by mass, based on 100 parts by mass of EVA, and one or more types are mixed and used.

  In addition, the EVA adhesive layer according to the present invention may further contain a small amount of an ultraviolet absorber, an infrared absorber, an anti-aging agent, a coating processing aid, a colorant, and the like. A small amount of a filler such as hydrophobic silica or calcium carbonate may be included.

  For example, after the EVA and the above-mentioned additive are mixed and kneaded with an extruder, a roll or the like, the adhesive layer is formed into a predetermined shape by a film forming method such as a calendar, roll, T-die extrusion, or inflation. Manufactured by.

  A protective layer may be provided on the antireflection layer. The protective layer is preferably formed in the same manner as the hard coat layer.

  The material of the release sheet provided on the transparent adhesive layer is preferably a transparent polymer having a glass transition temperature of 50 ° C. or higher. Examples of such a material include polyesters such as polyethylene terephthalate, polycyclohexylene terephthalate, and polyethylene naphthalate. In addition to polyamide resins such as nylon resins, nylon 46, modified nylon 6T, nylon MXD6, polyphthalamide, ketone resins such as polyphenylene sulfide and polythioether sulfone, and sulfone resins such as polysulfone and polyether sulfone, Mainly composed of polymers such as polyether nitrile, polyarylate, polyether imide, polyamide imide, polycarbonate, polymethyl methacrylate, triacetyl cellulose, polystyrene, polyvinyl chloride That the resin can be used. Of these, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polystyrene, and polyethylene terephthalate can be suitably used. The thickness is preferably 10 to 200 μm, particularly preferably 30 to 100 μm.

  In the optical filter of the present invention, for example, a mesh-like conductive layer, a hard coat layer, an antireflection layer, and the like are sequentially provided on one surface of a long transparent film, and then a near infrared ray is provided on the other surface of the transparent film. It can manufacture by providing an absorption layer and a transparent adhesive layer. The installation of each layer may be performed continuously or in a batch. An optical filter can be obtained by cutting the long laminate thus obtained. As a coating machine used when applying (applying) each layer to a long transparent film, a slit die, a lip direct, a lip reverse, or the like can be used. When both surfaces are applied simultaneously, a double-sided simultaneous coating machine in which lip dies are arranged on both sides is generally used.

  The display optical filter of the present invention thus obtained is used by being bonded to the surface of an image display glass plate of a display such as a PDP.

  Since the PDP display device of the present invention uses a plastic film as the transparent substrate, the optical filter of the present invention can be directly bonded to the surface of the glass plate, so that one transparent film is used. In this case, the PDP itself can contribute to weight reduction, thickness reduction, and cost reduction. Compared with the case where a front plate made of a transparent molded body is installed on the front side of the PDP, an air layer having a low refractive index can be eliminated between the PDP and the PDP filter, so that visible light reflection due to interface reflection can be achieved. Problems such as an increase in rate and double reflection can be solved, and the visibility of the PDP can be further improved.

Therefore, the display having the optical filter of the present invention is excellent in antireflection effect and antistatic property, hardly emits dangerous electromagnetic waves, is easy to see, hardly has dust and the like, and has excellent dimensional stability. .

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to a following example.

[Example 1]
<Preparation of optical filter for display>
(1) Formation of mesh-like conductive layer On an easy-adhesion layer of a long polyethylene terephthalate film (width: 600 mm, length 100 m) having a thickness of 100 μm having an easy-adhesion layer (polyester polyurethane; thickness 100 nm) on the surface, A 20% aqueous solution of polyvinyl alcohol was printed in dots. The size of one dot is a square shape with one side of 234 μm, the interval between the dots is 20 μm, and the dot arrangement is a square lattice. The printing thickness is about 5 μm after drying.

  On top of that, copper was vacuum-deposited to an average film thickness of 4 μm. Next, it was immersed in water at room temperature and rubbed with a sponge to dissolve and remove the dot portion, then rinsed with water and dried to form a mesh-like conductive layer on the polyethylene film.

  The conductive layer on the film surface had a square lattice shape corresponding to the negative pattern of dots accurately, the line width was 20 μm, and the aperture ratio was 77%. The average thickness of the conductive layer (copper layer) was 4 μm. The surface roughness (Ra) was 1.88.

(2) Formation of hard coat layer The following formulation:
Dipentaerythritol hexaacrylate (DPHA; manufactured by Nippon Kayaku Co., Ltd.) 20 parts by mass Bisphenol A diacrylate (A-BPE-4, manufactured by Shin-Nakamura Chemical Co., Ltd.) 80 parts by mass Methyl ethyl ketone 100 parts by mass Toluene 100 parts by mass Irgacure 184 (Ciba Specialty Chemicals) 4 parts by mass

A coating liquid obtained by mixing the above was applied onto the mesh-like conductive layer using a bar coater and cured by ultraviolet irradiation. Thereby, a hard coat layer (refractive index of 1.52) having a thickness of 5 μm was formed on the mesh-like conductive layer.

  Thereby, an optical filter for display was obtained.

[Example 2]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Dipentaerythritol hexaacrylate (DPHA) 50 parts by mass Bisphenol A diacrylate (A-BPE-4, manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass Methyl ethyl ketone 100 parts by mass Toluene 100 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 4 parts by mass

[Example 3]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Trimethylolpropane triacrylate (TMPT) 100 parts by weight Methyl ethyl ketone 100 parts by weight Toluene 100 parts by weight Irgacure 184 (manufactured by Ciba Specialty Chemicals) 4 parts by weight

[Example 4]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Pentaerythritol triacrylate (A-TMM-3; manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass Dipropylene glycol diacrylate (PO2 mol)
(APG-100; manufactured by Shin-Nakamura Chemical Co., Ltd.) 50 parts by mass Methyl ethyl ketone 100 parts by mass Toluene 100 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 4 parts by mass

[Example 5]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Pentaerythritol triacrylate (A-TMM-3; manufactured by Shin-Nakamura Chemical Co., Ltd.) 25 parts by mass Dipropylene glycol diacrylate (PO2 mol)
(APG-100; manufactured by Shin-Nakamura Chemical Co., Ltd.) 25 parts by mass Sun colloid HX-305M5
(SnO ₂ —ZrO ₂ —Sb ₂ O ₅ —SiO ₂ / methanol = 30/70; particle size 15 μm, manufactured by Nissan Chemical Industries, Ltd. 160 parts by mass Methyl ethyl ketone 45 parts by mass Toluene 45 parts by mass Irgacure 184 (Ciba Specialty Chemicals) 4 parts by mass

[Example 6]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Pentaerythritol triacrylate (A-TMM-3; manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Dipropylene glycol diacrylate (PO2 mol)
(APG-100; manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Sun colloid HX-305M5
(SnO ₂ —ZrO ₂ —Sb ₂ O ₅ —SiO ₂ / methanol = 30/70; particle size 15 μm, manufactured by Nissan Chemical Industries, Ltd.) 230 parts by mass Methyl ethyl ketone 20 parts by mass Toluene 20 parts by mass Irgacure 184 (Ciba Specialty Chemical) 4 parts by mass

[Comparative Example 1]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Bisphenol A diacrylate (A-BPE-4, manufactured by Shin-Nakamura Chemical Co., Ltd.) 100 parts by mass Methyl ethyl ketone 100 parts by mass Toluene 100 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 4 parts by mass

[Comparative Example 2]
An optical filter for display was obtained in the same manner as in Example 1 except that the composition of the hard coat layer was changed to the composition as described below.

Formula:
Dipentaerythritol hexaacrylate (DPHA) 100 parts by mass Methyl ethyl ketone 100 parts by mass Toluene 100 parts by mass Irgacure 184 (manufactured by Ciba Specialty Chemicals) 4 parts by mass

[Example 7]
Further, a display optical filter was obtained in the same manner as in Example 1 except that the following layers were provided.

(3) Formation of low refractive index layer The following formulation:
Opstar JN-7212 (manufactured by JSR Corporation) 100 parts by weight Methyl ethyl ketone 117 parts by weight Methyl isobutyl ketone 117 parts by weight

The coating liquid obtained by mixing was applied on the hard coat layer using a bar coater, dried in an oven at 80 ° C. for 5 minutes, and then cured by ultraviolet irradiation. Thereby, a low refractive index layer (refractive index 1.42) having a thickness of 90 nm was formed on the hard coat layer.

(4) Formation of near-infrared absorbing layer (having color tone correction function)
Polymethylmethacrylate 30 parts by mass TP-2 (manufactured by Yamada Chemical Co., Ltd.) 0.4 parts by mass Plast Red 8380 (manufactured by Arimoto Chemical Industry Co., Ltd.) 0.1 parts by mass CIR-1085 (Nippon Carlit Co., Ltd.) Manufactured) 1.3 parts by weight IR-10A (manufactured by Nippon Shokubai Co., Ltd.) 0.6 parts by weight Methyl ethyl ketone 152 parts by weight Methyl isobutyl ketone 18 parts by weight of a coating solution obtained on the back of the polyethylene film It was applied using a bar coater and dried in an oven at 80 ° C. for 5 minutes. As a result, a near-infrared absorbing layer (having a color tone correcting function) having a thickness of 5 μm was formed on the polyethylene film.

(5) Formation of transparent adhesive layer The following formulation:
SK Dyne 1811L (manufactured by Soken Chemical Co., Ltd.) 100 parts by mass Curing agent L-45 (manufactured by Soken Chemical Co., Ltd.) 0.45 parts by mass Toluene 15 parts by mass Ethyl acetate 4 parts by mass Was coated on the near infrared absorbing layer using a bar coater and dried in an oven at 80 ° C. for 5 minutes. This formed a 25-micrometer-thick transparent adhesive layer on the near-infrared absorption layer.

  Thereby, an optical filter for display was obtained.

  The obtained optical filter for display was evaluated as follows.

[Evaluation of optical filter]
(1) Surface roughness The surface roughness (Ra) was determined by using a contact surface roughness meter (Talystep; manufactured by Taylor Hopson Co., Ltd.), and the center line average roughness of the hard coat layers obtained in the examples and comparative examples. Measure (Ra). The center line is the center line in the length direction of the long PET film.

(2) Pencil hardness Pencil hardness is measured based on JIS-K-5600 (2002) about the hard coat layer obtained by the Example and the comparative example.

(3) Curing Shrinkage Ratio The specific gravity before and after curing of the hard coat layer obtained in the examples and comparative examples was measured. The specific gravity is measured according to JIS-K-6833.

And the cure shrinkage rate is
[{(Specific gravity before curing) − (specific gravity before curing)} / {specific gravity before curing}] × 100
Calculated by

  The results are shown in Table 1.

  The PDP filters obtained in Examples 1 to 6 were excellent in both film strength and surface flatness. This is presumed to be because the cure shrinkage is in an appropriate range.

  Further, the optical filter of Example 7 having the hard coat layer of Example 1 and further provided with an antireflection layer, a near-infrared absorbing layer, and the like exhibited excellent electromagnetic shielding properties and high transmittance.

It is a schematic sectional drawing which shows an example of the basic composition of the optical filter of this invention. It is the schematic explaining the formation method of the mesh-shaped electroconductive layer by the printing mesh method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Display optical filter 12 Transparent film 13 Mesh-like electroconductive layer 16 Hard-coat layer 17 Antireflection layer 14 Near-infrared absorption layer 15 Transparent adhesive layer

Claims (18)

An optical filter for display comprising at least one transparent film, a mesh-like conductive layer provided thereon, and a functional layer provided on the mesh-like conductive layer,
An optical filter for display, wherein the surface of the functional layer has a surface roughness (Ra) of less than 0.2.   The optical filter for display according to claim 1, wherein the surface of the functional layer has a pencil hardness of 2H or more.   The optical filter for display according to claim 1 or 2, wherein the functional layer is a hard coat layer.   The optical filter for display according to any one of claims 1 to 3, wherein the functional layer has a curing shrinkage rate in the range of 2 to 10%. An optical filter for display in which a mesh-like conductive layer and a hard coat layer are provided in this order on one surface of a transparent film, and a near-infrared absorbing layer is provided on the other surface,
An optical filter for display, wherein the surface of the hard coat layer has a surface roughness (Ra) of less than 0.2 and a pencil hardness of 2H or more.   The display-use optical filter according to claim 5, wherein the hard coat layer has a curing shrinkage in the range of 2 to 10%.   The optical filter for display according to any one of claims 1 to 6, wherein the mesh-shaped conductive layer has a thickness of 1 to 10 µm.   The optical filter for display according to any one of claims 1 to 7, wherein the mesh-shaped conductive layer includes a metal vapor deposition film.   The optical filter for display according to any one of claims 3 to 8, wherein a low refractive index layer having a refractive index lower than that of the hard coat layer is further formed on the hard coat layer.   The optical filter for a display according to any one of claims 5 to 9, wherein a transparent adhesive layer is provided on the surface of the near-infrared absorbing layer opposite to the transparent film.   The optical filter for display according to any one of claims 5 to 10, wherein the near-infrared absorbing layer has adhesiveness.   The optical filter for display according to claim 1, wherein the transparent film is a plastic film.   The optical filter for a display according to any one of claims 10 to 12, wherein a release sheet is provided on the transparent adhesive layer or the adhesive near-infrared absorbing layer. An optical filter for display comprising at least one transparent film, a mesh-like conductive layer provided thereon, and a functional layer provided on the mesh-like conductive layer,
An optical filter for display, wherein the functional layer has a cure shrinkage in the range of 2 to 10%. An optical filter for display in which a mesh-like conductive layer and a hard coat layer are provided in this order on one surface of a transparent film, and a near-infrared absorbing layer is provided on the other surface,
An optical filter for display, wherein the hard coat layer has a curing shrinkage in the range of 2 to 10%.   It is a filter for plasma display panels, The optical filter for displays of any one of Claims 1-15.   The display optical filter of any one of Claims 1-15 is affixed on the surface of the image display glass plate, The display characterized by the above-mentioned.   A plasma display panel, wherein the display optical filter according to any one of claims 1 to 15 is bonded to a surface of an image display glass plate.

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