JP2005277438A - Manufacturing method for filter used for display unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a low-cost filter having a high visible-region transmission factor and superior in display image visibility, when a conductive mesh layer is used for electromagnetic wave shielding. <P>SOLUTION: A transparent substrate (A) 20, conductive mesh layer (B) 10 for shielding electromagnetic waves, a translucent adhesive material (D) 20 containing a colorant and functional films (C) 40, 50 are laminated. The functional film has at least one function from among hard coating, antireflection properties, light prevention, electrostatic prevention, soil resistance, ultraviolet ray cutting and near-infrared ray cutting properties. After lamination is formed into a C/A/B/D/C layer structure, pressurization is performed on the lamination. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

    The present invention relates to a method for manufacturing a display filter capable of providing functions such as shielding of electromagnetic waves and shielding of near infrared rays when installed on a display screen such as a plasma display.

  Displays are remarkably widespread for televisions, personal computers, and the like, and are becoming thinner and larger. Plasma displays are attracting attention as large thin displays. However, the plasma display generates strong leakage electromagnetic fields (electromagnetic waves) and near infrared rays due to its structure and operating principle. Electromagnetic waves are regulated by the Electrical Appliance and Material Control Law and the like, and must be kept within the standard values. In addition, near-infrared light has a problem of causing malfunctions by acting on peripheral electronic devices such as cordless phones, and cuts light in the wavelength range of 800 to 1000 nm, which is the near-infrared region, to a level where there is no practical problem. There is a need.

  To shield electromagnetic waves, it is necessary to cover the display surface with a highly conductive material, such as a metal fiber coated with a synthetic fiber or metal fiber mesh, or etched into a lattice pattern after forming a metal film, for example. A conductive mesh layer made of an etching film can be used.

  Moreover, since the display part of a plasma display generally has low strength, it is necessary to protect it. As a member that protects the display unit and blocks near infrared rays and electromagnetic waves emitted from the plasma display, a plate-shaped plasma display filter, that is, a front filter, is installed on the front of the display with the above performance added. It is necessary to paste on the surface of the plasma display. Further, since the visible light transmittance is remarkably low due to the arrangement on the front surface, or if there is a reflection of illumination or the like, the brightness of the display, the sharpness of the image, and the visibility are deteriorated.

  As described above, the display filter is required to have a plurality of functions, and in order to satisfy them, it is necessary to stack layers having each function. For example, a functional film C such as an antireflection film or a near-infrared absorbing film needs to be bonded to the transparent mesh A of the transparent substrate A having the conductive mesh layer B with a transparent adhesive material D. However, when the functional film is pasted on the main surface of the conductive mesh layer B via the adhesive material D, the conductive mesh layer has irregularities, so that the air bubbles are caught in the concave portions, and there is turbidity. There was a problem that it became a display filter with insufficient translucency. In order to solve this problem, a transparent resin D is embedded in the recesses of the conductive mesh layer B in advance, and a transparent treatment that does not turbidize the air bubbles is performed after bonding, but the number of steps increases. Not only that, but the low yield increases the cost.

  An object of the present invention is to provide a manufacturing method of a display filter that can realize a filter having high visible region transmittance and excellent display image visibility at a low cost when a conductive mesh layer is used for electromagnetic wave shielding. That is.

  As a result of intensive studies to solve the above problems, the present inventors perform pressure treatment after bonding the functional film C onto the conductive mesh layer B via the adhesive material D. Has found a method for producing a display filter that can increase the visible light transmittance of the light-transmitting part of the laminate by 10% or more and can eliminate the transparentization treatment of the conductive mesh layer, and has reached the present invention. .

That is, the present invention provides a transparent substrate (A),
A conductive mesh layer (B) having a thickness of 5 to 15 μm, a mesh pattern portion having a line width of 5 to 20 μm, a pitch of 150 to 400 μm and a surface resistance of 3 Ω / □ or less, for shielding electromagnetic waves;
The thickness of the conductive mesh layer (B) is set to d μm, and the translucent adhesive material (D) having a thickness set in a range of d μm or more and less than (d + 30) μm,
A functional film (C) having at least one of a hard coat property, antireflection property, antiglare property, antistatic property, antifouling property, ultraviolet ray cut property, and near infrared ray cut property is bonded to Forming a laminate having a layer structure of / B / D / C;
The laminate is subjected to a pressure treatment that is held for 10 minutes to 6 hours under a pressure of 0.4 MPa to 2 MPa, and the visible light transmittance of the light-transmitting portion of the laminate is changed by 10% or more before and after the pressure treatment. And a step of increasing the display filter.

The present invention is also characterized in that the second functional film (C) is bonded onto the transparent substrate (A) to form a laminate having a layer structure of C / A / B / D / C. To do.
Moreover, this invention is characterized by the pigment | dye containing at least 1 layer of a laminated body.

In the present invention, the conductive mesh layer (B) is formed with a conductive portion for electrical connection with an external ground.
The present invention is also characterized in that it is for a plasma display.

In the present invention, the transparent substrate (A) comprises a transparent adhesive material (22) and a first polymer film (21),
The conductive part (11) of the conductive mesh layer (B) is formed along the peripheral edge of the mesh pattern part (12).

In the present invention, the functional film (C) has a near-infrared absorber-containing layer (41), a second polymer film (43), and an antireflection material having hard coat properties, antistatic properties and antifouling properties. And a layer (42).
Moreover, this invention is a filter for a display obtained with the said manufacturing method.

  As described above in detail, according to the present invention, when a conductive mesh layer is used for shielding electromagnetic waves, a filter having high visible region transmittance and excellent display image visibility can be realized at low cost.

  Moreover, since a near-infrared shielding function and a toning function can be provided by containing a pigment | dye, it can be used conveniently as a display filter, such as a plasma display.

  The present invention can increase the visible light transmittance of the translucent part by 10% or more by performing pressure treatment after laminating the functional film on the conductive mesh layer via an adhesive material. It is characterized by a method for producing a display filter having excellent translucency and low cost.

(Transparent substrate)
Examples of the transparent substrate (A) for forming the conductive mesh layer (B) include inorganic compound molded products such as glass and quartz, and transparent organic polymer molded products. The transparent substrate (A) can be subjected to various known pretreatments necessary before forming the conductive mesh layer. For example, the transparent substrate (A) is printed with a colored frame such as black on the periphery of the display filter. Also good.

  When a glass plate is used for the transparent substrate (A), it is desirable to use a semi-tempered glass plate or a tempered glass plate that has been subjected to chemical strengthening processing or air-cooling strengthening processing in order to add mechanical strength. Considering the weight, the thickness is preferably about 1 to 4 mm.

  Since the polymer molding is light and difficult to break, it can be suitably used as a transparent substrate. The polymer molding may be transparent in the visible wavelength region, and specific examples thereof include polyethylene terephthalate, polyethersulfone, polystyrene, polyethylene naphthalate, polyarylate, polyetheretherketone, polycarbonate, polyethylene, Examples include, but are not limited to, polypropylene. These transparent polymer molded products may be in the form of a plate (sheet) or a film as long as the main surface is smooth, and may have a hard coat layer or the like. The transparent polymer film has flexibility, and the conductive mesh layer (B) can be continuously formed by a roll-to-roll method. Moreover, by sticking this to the glass of the display surface glass or the glass support of the filter for display, scattering when the glass is broken can be prevented. In this case, the thickness of the film is usually 10 to 250 μm.

  When a polymer film is used for the transparent substrate (A), the main surface opposite to the surface on which the conductive mesh layer (B) is formed is formed via a translucent adhesive or adhesive. It can be bonded to a glass plate or a translucent plastic plate as a support for a display filter. From the standpoint of mechanical strength, lightness, and resistance to cracking, a plastic plate is desirable, but a glass plate can also be suitably used because of its thermal stability with little deformation due to heat. Specific examples of the plastic plate include acrylic resin such as polymethyl methacrylate (PMMA), polycarbonate resin, transparent ABS resin and the like, but are not limited to these resins. In particular, PMMA can be suitably used because of its high transparency in a wide wavelength region and high mechanical strength. The thickness of the plastic plate is not particularly limited as long as it has sufficient mechanical strength and rigidity to maintain flatness without bending, but is usually about 1 mm to 10 mm.

  In this embodiment, when the polymer film on which the conductive mesh layer (B) is formed is bonded to a glass plate or a plastic plate, the glass plate or the plastic plate bonded to the polymer film is put together to form a transparent substrate. This is referred to as (A).

(Conductive mesh layer)
A conductive mesh layer (B) is used for shielding electromagnetic waves. The mesh shape may be a lattice shape or a honeycomb shape, and is not particularly limited. As a method for forming the conductive mesh layer (B) on the transparent substrate (A), a conventionally known method can be used. For example, 1) Conductive ink is screen-printed or gravure printed on the transparent substrate (A). A method of pattern printing by a known printing method, 2) a method of bonding a knitted fabric made of conductive fibers with an adhesive or an adhesive, and 3) an adhesive or an adhesive with a metal foil made of copper, aluminum, nickel, or the like. 4) a method of patterning after bonding through a material, 4) a method of patterning after forming a metal thin film made of copper, aluminum, nickel or the like by various known thin film forming methods such as vapor deposition, sputtering, electroless plating, etc. There is no particular limitation.

  The patterning methods 3) and 4) are not particularly limited, and examples thereof include a photolithography method. Specifically, a photosensitive resist is coated on a metal foil or a metal thin film, or a photosensitive resist film is laminated, a pattern mask is adhered, exposed to light, and then developed with a developer to form a resist pattern. A desired conductive mesh layer (B) is formed by eluting metal other than the pattern portion with an etching solution.

  The thickness of the conductive mesh layer (B) is about 0.5 to 20 μm, and the layer thickness is determined by the required electromagnetic shielding ability, that is, the conductivity, the required aperture ratio, and the method of forming the conductive mesh layer. Is done. The conductivity necessary for shielding electromagnetic waves of the plasma display is 3Ω / □ or less, preferably 1Ω / □ or less, and more preferably 0.3Ω / □ or less in terms of surface resistance. If the thickness of the conductive mesh layer (B) is too thin, the conductivity is insufficient, and if it is too thick, the cost is increased.

  The mesh pattern portion of the conductive mesh layer (B) is suitable because the narrower the line width, the wider the pitch, the higher the aperture ratio, that is, the transmittance, and the less likely to cause visible interference fringes with display pixels. It is. However, if the aperture ratio is increased too much, the conductivity of the conductive mesh layer (B) is insufficient, so that a line width of 5 to 20 μm and a pitch of 150 to 400 μm can be suitably employed. Furthermore, when the mesh pattern portion is, for example, a lattice pattern, the mesh pattern portion has a certain amount of lines with respect to the line where the pixels are arranged so as not to cause visible interference fringes with the pixels of the display arranged side by side. It is important to have an angle (bias angle). The bias angle that does not cause interference fringes varies depending on the pixel pitch and the pitch / line width of the mesh pattern portion, and is not particularly limited.

  When the conductive mesh layer (B) is made of a metal such as copper, aluminum or nickel, a layer containing a black pigment or a black dye at the surface and / or the interface with the transparent substrate (A), or chromium, etc. It is preferable to have a black layer made of the above, whereby reflection by metal can be prevented, and a display filter having excellent contrast and visibility can be obtained.

  The conductive mesh layer (B) must have a mesh pattern portion other than a portion that becomes a light transmitting portion when installed on a display, that is, a portion that is not a display portion or a portion that is hidden by frame printing. Alternatively, these portions may be unpatterned, for example, a solid metal foil layer. In addition, if the solid portion that is not patterned is black, it can be used as frame printing for a display filter as it is.

(Functional film)
In the present invention, the functional film (C) is laminated on the conductive mesh layer (B) formed on the main surface of the transparent substrate (A) through the translucent adhesive (D). Get the body. Here, the functional film (C) has a function selected from one or more of hard coat properties, antireflection properties, antiglare properties, antistatic properties, antifouling properties, ultraviolet ray cut properties, and near infrared ray cut properties. Have.

  The functional film (C) in the present invention may be a transparent polymer film in which one or more functional films having one or more of the above functions are formed, or a transparent polymer film having each function. For the formation of the functional film, in the case of forming an inorganic compound thin film, any of the conventionally known methods such as sputtering, ion plating, vacuum deposition, wet coating, etc. can be adopted. Conventionally known methods such as a method of drying and curing after wet coating such as bar coating method, reverse coating method, gravure coating method, die coating method and roll coating method can be adopted.

  In addition, the functional film (C) is attached to the other main surface of the transparent substrate (A) where the conductive mesh layer (B) is not formed via a translucent adhesive or adhesive. May be combined.

  As a laminated structure, for example, functional film (C) / translucent adhesive material (D) / conductive mesh layer (B) / polymer film / translucent adhesive material / functional film (C), or , Functional film (C) / translucent adhesive (D) / conductive mesh layer (B) / polymer film / translucent adhesive / glass / translucent adhesive / functional film (C ).

  If a display such as a lighting fixture is reflected on the display screen, the display screen becomes difficult to see. Therefore, the functional transparent layer (C) has anti-reflection (AR: anti-reflection) properties for suppressing external light reflection, Alternatively, it preferably has a function of anti-glare (AG: anti-glare) that prevents reflection of a mirror image or anti-glare and anti-glare (ARAG) that has both characteristics. Further, when the visible light reflectance on the display filter surface is low, not only the reflection is prevented but also the function of improving the contrast and the like is achieved.

  The functional film (C) having antireflection properties has an antireflection film, and specifically has a refractive index of 1.5 or less, preferably 1.4 or less in the visible region, and has a high fluorine-based transparency. Molecular resin, magnesium fluoride, silicon-based resin, silicon oxide thin film, etc. formed as a single layer with an optical film thickness of, for example, 1/4 wavelength, metal oxide, fluoride, silicide, nitride with different refractive index There are two or more layers of thin films of inorganic compounds such as sulfides or organic compounds such as silicon resins, acrylic resins, and fluorine resins. The visible light reflectance of the surface of the functional film (C) having antireflection properties is 2% or less, preferably 1.3% or less, more preferably 0.8% or less.

  The functional film (C) having an antiglare property has an antiglare film that is transparent to visible light having a minute uneven surface state of about 0.1 μm to 10 μm. Specifically, acrylic resin, silicon resin, melamine resin, urethane resin, alkyd resin, thermosetting resin such as fluorine resin, photocurable resin, silica, organic silicon compound, melamine, acrylic, etc. Inorganic particles or organic compound particles dispersed in an ink are applied and cured on a substrate. The average particle diameter of the particles is 1 to 40 μm. Alternatively, the antiglare property can also be obtained by applying the above thermosetting or photocurable resin to a substrate and pressing and curing a mold having a desired haze or surface state, but it is not necessarily limited to these methods. It is not something. The haze of the functional film (C) having antiglare property is 0.5% or more and 20% or less, preferably 1% or more and 10% or less. If the haze is too small, the antiglare property is insufficient, and if the haze is too large, the transmitted image sharpness tends to be low.

  In order to add scratch resistance to the display filter, it is also preferable that the functional film (C) has a hard coat property. Examples of the hard coat film include thermosetting or photocurable resins such as acrylic resins, silicon resins, melamine resins, urethane resins, alkyd resins, and fluorine resins. There is no particular limitation. The thickness of these films is preferably about 1 to 50 μm. As for the surface hardness of the functional transparent layer (C) having hard coat properties, the pencil hardness according to JIS (K-5400) is at least H, preferably 2H, more preferably 3H or more.

Furthermore, the display filter is likely to be attached with dust due to electrostatic charging, and may be discharged and receive an electric shock when a human body comes into contact with it, so that an antistatic treatment may be required. Therefore, the functional film (C) may have conductivity in order to impart antistatic ability. The conductivity required in this case may be about 10 ¹¹ Ω / □ or less in terms of surface resistance. Examples of the conductive layer include known transparent conductive films such as ITO, and conductive films in which conductive ultrafine particles such as ITO ultrafine particles and tin oxide ultrafine particles are dispersed.

  Furthermore, it is preferable that the surface of the functional film (C) has antifouling properties so that fingerprints and the like can be easily prevented and removed when they become dirty. As for what has antifouling property, it has non-wetting property with respect to water and / or fats and oils, for example, a fluorine compound and a silicon compound are mentioned.

  Furthermore, in order to prevent the dye contained in the display filter from being deteriorated by the light emitted from the display or the ultraviolet rays contained in the external light, the functional transparent layer (C) has an ultraviolet-cutting property. May be. For example, an antireflection film consisting of a single layer or multiple layers of an inorganic thin film that absorbs ultraviolet rays, or a hard coat film containing an ultraviolet absorber.

(Lamination)
In the present invention, the bonding (lamination) is performed via an arbitrary pressure-sensitive adhesive material D or adhesive that is transparent to visible light. Specifically, acrylic adhesives, silicon adhesives, urethane adhesives, polyvinyl butyral adhesives (PVB), ethylene-vinyl acetate adhesives (EVA), etc., polyvinyl ether, saturated amorphous polyester, melamine resins, etc. As long as it has practical adhesive strength, it may be in the form of a sheet or liquid. The pressure-sensitive adhesive can be suitably used as a pressure-sensitive adhesive. Bonding is performed by laminating each member after applying the sheet-like adhesive material or after applying the adhesive. The liquid material is an adhesive that is cured by being left at room temperature or heated after coating and bonding. Examples of the coating method include a bar coating method, a reverse coating method, a gravure coating method, a die coating method, and a roll coating method, and are selected in consideration of the type of adhesive, viscosity, coating amount, and the like. The thickness of the layer is not particularly limited, but is 0.5 μm to 50 μm, preferably 1 μm to 30 μm. It is preferable that the surface on which the adhesive layer is formed and the surface to be bonded are previously improved in wettability by an easy adhesion treatment such as an easy adhesion coat or a corona discharge treatment.

  In this invention, when bonding a functional film (C) on an electroconductive mesh layer (B), a translucent adhesive material (D) is used especially. Specific examples of the translucent adhesive material (D) are the same as described above, but the thickness is preferably such that the concave portion of the conductive mesh layer (B) can be sufficiently embedded, and the thickness of the conductive mesh layer (B). If the thickness is too thin, a gap is formed due to insufficient embedding, and the transmittance cannot be sufficiently improved even if the processing described later is performed. If the translucent adhesive material is too thick, problems such as an increase in the cost for producing the adhesive material occur. When the thickness of the conductive mesh layer (B) is d μm, the present inventors have a thickness of the translucent adhesive material (D) in the range of (d−2) μm or more and less than (d + 30) μm. I found it preferable.

  As described above, when a film is bonded to the conductive mesh layer (B) having irregularities via an adhesive material, bubbles are trapped in the concave portions due to the irregularities of the conductive mesh layer, causing turbidity and lack of translucency. It becomes a display filter.

  The visible light transmittance of the display filter is preferably 35 to 85%. More preferably, it is 40 to 75%. If it is less than 35%, the luminance is too low and the visibility is deteriorated.

  It is calculated according to JIS (R-3106) from the wavelength dependency of the visible light transmittance in the present invention and the transmittance in the visible light region.

(Pressure treatment)
The present inventors have found that the transmittance of the laminate can be improved by using a translucent adhesive material (D) having a sufficient thickness and performing a pressure treatment. By performing the pressure treatment after bonding, the gas that has entered between the members at the time of bonding can be defoamed or dissolved in an adhesive material, and the turbidity of the laminate can be eliminated.

  The pressure treatment needs to use a method and conditions that can eliminate the turbidity of the laminate due to the entrained bubbles and sufficiently improve the transmittance. It is desirable that the visible light transmittance can be improved by 10% or more. Here, the rate of change is a percentage of the amount of change in the visible light transmittance after the treatment with respect to the visible light transmittance before the pressure treatment.

  Examples of the pressurizing method include a method in which a laminate is sandwiched between flat plates, a method of pressing while pressing between nip rolls, and a method of pressing in a pressure vessel, but are not particularly limited. The method of pressurizing in the pressure vessel is preferable because the entire laminate is uniformly pressurized and there is no unevenness in pressurization, and a plurality of laminates can be processed at a time. An autoclave device can be used as the pressurized container.

  As the pressurizing condition, the higher the pressure is, the more air bubbles can be eliminated, and the processing time can be shortened. .About.2 MPa to 2 MPa, preferably 0.4 to 1.3 MPa, and 0.4 MPa to 2 MPa in the present invention. The pressurization time varies depending on the pressurization conditions and is not particularly limited. However, if the pressurization time is too long, the processing time is increased and the cost is increased. Therefore, the holding time is preferably 6 hours or less under appropriate pressurization conditions. Particularly in the case of a pressurized container, it is preferable to hold for about 10 minutes to 3 hours after reaching the set pressure, and in the present invention, it is 10 minutes to 6 hours.

  Moreover, it may be preferable if it can heat simultaneously at the time of pressurization. By heating, the fluidity of the translucent adhesive material (D) temporarily rises and it becomes easy to defoam the entrained bubbles, or the bubbles easily dissolve in the adhesive material. Depending on the heat resistance of each member constituting the laminate, the heating condition is not less than room temperature and not more than 80 ° C., but is not particularly limited.

  Furthermore, the pressure treatment or the pressure heating treatment is preferable because it can improve the adhesion between the members constituting the laminated body after bonding.

(Toning and optical characteristics)
As described above, since the plasma display generates intense near-infrared rays, it is necessary to cut it to a level where there is no practical problem. It is a wavelength range of 800 to 1000 nm which is a problem, and the transmittance in the wavelength range is required to be 20% or less, preferably 10% or less. In addition, a display filter used in a plasma display is required to have a transmission color of neutral gray or blue gray. This is because it is necessary to maintain or improve the light emission characteristics and contrast of the plasma display, and white color having a slightly higher color temperature than standard white color may be preferred. Furthermore, the color plasma display is said to have insufficient color reproducibility, and it is preferable to selectively reduce unnecessary light emission from the phosphor or discharge gas which is the cause. In particular, the emission spectrum of red display shows several emission peaks ranging from about 580 nm to about 700 nm, and the emission intensity on the short wavelength side is relatively strong and the red emission is not good in color purity close to orange. There is a problem.

  These optical properties can be controlled by using a dye. That is, a desired optical characteristic can be obtained by using a near-infrared absorber for cutting near-infrared light and using a dye that selectively absorbs unnecessary light-emitting for reducing unnecessary light-emitting. As for the color tone of the display filter, a desired color tone can be obtained by using a dye having appropriate absorption in the visible region.

  As a method for containing a dye, (1) a method using a polymer film or a resin plate in which at least one dye is kneaded with a transparent resin, and (2) at least one dye, resin or resin. A method of using a polymer film or a resin plate prepared by a casting method by dispersing and dissolving in a monomer / organic solvent resin concentrate, and (3) adding at least one dye to a resin binder and an organic solvent. There are a method of using a polymer coated on a polymer film or a resin plate as a paint, and (4) a method of using a transparent adhesive material containing at least one pigment, and the method is not limited thereto. The term “inclusion” as used in the present invention means that it is contained in a layer such as a base material or a coating film or an adhesive material, and of course, is applied to the surface of the base material or layer.

  The dye is a general dye or pigment having a desired absorption wavelength in the visible region, or a near-infrared absorber, and the type thereof is not particularly limited. For example, anthraquinone, phthalocyanine, methine, azomethine , Oxazine, azo, styryl, coumarin, porphyrin, dibenzofuranone, diketopyrrolopyrrole, rhodamine, xanthene, pyromethene, dithiol, diiminium compounds, etc. Organic dyes. The type / concentration is determined by the absorption wavelength / absorption coefficient of the dye, the transmission characteristics / transmittance required for the display filter, and the type / thickness of the medium or coating film to be dispersed, and is not particularly limited.

  The plasma display panel has a high temperature on the surface of the panel, and when the environmental temperature is high, the temperature of the display filter provided on the screen also increases. Therefore, the dye has heat resistance that does not deteriorate significantly due to decomposition at 80 ° C., for example. It is suitable. In addition, when the dye is poor in light resistance and deterioration of the light emission of the plasma display or external light due to ultraviolet rays / visible rays becomes a problem, by using a member containing an ultraviolet absorber or a member that does not transmit ultraviolet rays, It is important to use a pigment that does not significantly deteriorate due to ultraviolet rays or visible light. The same applies to humidity and a combined environment in addition to heat and light. When it deteriorates, the transmission characteristics of the display filter change. Furthermore, in order to disperse in a medium or a coating film, solubility and dispersibility in an appropriate solvent are also important.

  Two or more types of pigments having different absorption wavelengths may be contained in one medium or coating film, or two or more media and coating films containing pigments may be included.

  In the present invention, the methods (1) to (4) containing the above-mentioned pigment are, in the present invention, a transparent substrate (A) containing a pigment, a functional film (C) containing a pigment, and a translucent adhesive containing a pigment. It can be used for the display filter of the present invention in any one or more forms of the material (D), a light-transmitting pressure-sensitive adhesive material or an adhesive containing a dye used for bonding.

(Electromagnetic wave shielding function)
For devices that require electromagnetic shielding, a metal layer is provided inside the case of the device, or a conductive material is used for the case to block radio waves. When the display portion needs to be transparent like a display, a window-like display filter is installed. Since the electromagnetic wave induces an electric charge after being absorbed in the conductive layer, if the electric charge is not released by taking the ground, the display filter oscillates again as an antenna and the electromagnetic wave shielding ability is lowered. Therefore, the display filter and the ground portion of the display body must be in electrical contact. Therefore, the above-mentioned transparent adhesive material (D) and functional film (C) need to be formed on the conductive mesh layer (B) leaving a conducting portion for ensuring conduction from the outside. The shape of the conducting portion is not particularly limited, but it is important that there is no gap for electromagnetic wave leakage between the display filter and the display body. Therefore, it is preferable that the conductive portion is provided continuously at the peripheral edge of the conductive mesh layer (B). That is, it is preferable that the conducting portion is provided in a frame shape except for the central portion which is the display portion of the display.

  The conducting part may be a mesh pattern layer or may be an unpatterned layer of metal foil, for example.

  In order to protect the conduction part and to improve electrical contact, it is preferable to form an electrode in the conduction part. The electrode shape is not particularly limited. However, it is preferable that it is formed so as to cover all the conductive portions. For example, when the conductive part is not patterned like a solid metal foil and / or the mechanical strength of the conductive part is sufficiently strong, the conductive part itself can be used as an electrode.

  The material used for the electrode is a single or a combination of two or more of silver, copper, nickel, aluminum, chromium, iron, zinc, carbon, etc. in terms of conductivity, resistance to contact and adhesion to a transparent conductive film. Alternatively, a paste made of a synthetic resin and a mixture of these simple substances or alloys, or a paste made of a mixture of borosilicate glass and these simple substances or alloys can be used. Conventionally known methods can be employed for printing and coating the paste. Moreover, a commercially available conductive tape can also be used conveniently. The conductive tape has conductivity on both sides, and a single-sided adhesive type and a double-sided adhesive type using a carbon-dispersed conductive adhesive can be suitably used. The thickness of the electrode is not particularly limited, but is about several μm to several mm.

  With the above-described configuration, it is possible to realize a display filter having excellent optical characteristics that can maintain or improve the image quality without significantly impairing the luminance of the plasma display. In addition, it excels in electromagnetic shielding ability to block electromagnetic waves that are said to be harmful to health generated from plasma displays, and in addition, it efficiently cuts near-infrared rays near 800 to 1000 nm generated from plasma displays. It is possible to provide a low-cost display filter that does not adversely affect the wavelengths used by the remote control of the device, transmission optical communication, and the like and can prevent malfunctions thereof.

  Next, an embodiment of the present invention will be described in detail. The present invention is not limited by these.

(Example 1)
A biaxially stretched polyethylene terephthalate (hereinafter referred to as PET) film (thickness: 100 μm) 21 in which a 10 μm-thick copper foil that has been blackened on both sides is bonded via an adhesive is used as PET.
The surfaces were bonded to each other and bonded to a glass plate 23 having a thickness of 2.5 mm and an outer dimension of 950 mm × 550 mm through a transparent acrylic adhesive 22. The copper foil layer was patterned into a conductive mesh layer by patterning a lattice pattern having a line width of 12 μm, a pitch of 300 μm, and a bias angle of 60 ° by photolithography, leaving a peripheral edge of 15 mm. FIG. 1 is a plan view showing an example of the mesh pattern portion 12 of the conductive mesh layer. In FIG. 1, the conductive mesh layer (B) 10 includes a conductive portion 11 made of a solid copper having a width of 15 mm along the peripheral portion of the mesh pattern portion 12 and a mesh pattern portion 12 for covering the display screen.

  Next, a reflection made of a 100 μm-thick PET film, an antireflection layer, and a near-infrared absorber-containing layer is formed on the conductive mesh layer inside the peripheral part 20 mm through an acrylic translucent adhesive material having a thickness of 25 μm An infrared absorbing film near the prevention function (trade name Clearus AR / NIR, manufactured by Sumitomo Osaka Cement Co., Ltd.) was bonded. The acrylic light-transmitting pressure-sensitive adhesive layer contained a toning dye (PS-Red-G, PS-Violet-RC manufactured by Mitsui Chemicals) that adjusts the transmission characteristics of the display filter. Further, an antireflection film (trade name Realak 8201 manufactured by Nippon Oil & Fats Co., Ltd.) was bonded to the opposite main surface of the glass plate via an adhesive material to produce a display filter. A cross-sectional view showing an example of the configuration of the display filter is shown in FIG.

  In FIG. 2, a polymer film 21 is provided on the lower main surface of the glass plate 23 via a transparent adhesive material 22 to constitute a transparent substrate (A) 20. Furthermore, a conductive mesh layer (B) 10 including a translucent adhesive 13 is provided on the polymer film 21. Furthermore, a functional film (C) 40 is provided on the conductive mesh layer (B) 10 via a light-transmitting adhesive (D) 30 containing a pigment. The functional film (C) 40 is configured by laminating a near-infrared absorber-containing layer 41, a polymer film 43, and an antireflection layer 42 having hard coat properties, antistatic properties, and antifouling properties in this order. Is done.

  On the upper main surface of the glass plate 23, a functional film (adhesive material 51, polymer film 53, and antireflection layer 52 having hard coat properties, antistatic properties, and antifouling properties are laminated in this order ( C) 50 is provided.

  Next, this display filter was put in an autoclave container and subjected to pressure treatment under conditions of a temperature setting of 40 ° C., a pressure setting of 0.8 MPa, a pressurization time of 30 minutes, and a holding time of 30 minutes.

(Example 2)
A display filter was prepared in the same manner as in Example 1, and this display filter was placed in an autoclave container and subjected to pressure treatment under the conditions of no temperature setting, pressure setting of 0.4 MPa, pressurization time of 20 minutes, and holding time of 1 hour. .
(Comparative Example 1)
A display filter was prepared in the same manner as in Example 1, and no pressure treatment was performed.

  The translucent part of the display filter obtained by the production methods of Examples 1 and 2 and Comparative Example 1 obtained as described above was cut into a 5 cm square sample, and a spectrophotometer (U -3400), the sample was fixed at the sample side entrance of the reflection integrating sphere (light incident angle 6 °), and the total light transmittance of the measurement object at 300 to 800 nm was measured. The results are listed in (Table 1).

  As apparent from Table 1, the visible light transmittance could be surprisingly improved by applying the pressure treatment.

  Moreover, the filter for display obtained in Examples 1 and 2 has an electromagnetic wave shielding ability (surface resistance of 0.1 Ω / □ or less) and a near infrared ray cutting ability (transmittance of 300 to 800 nm of 15% or less) that is not problematic in practice. It had excellent visibility due to the antireflection layers on both sides.

The present invention can be implemented in the following embodiments.
(1) Transparent substrate (A), conductive mesh layer (B) for shielding electromagnetic waves, translucent adhesive (D), hard coat property, antireflection property, antiglare property, antistatic property A laminate having a layer structure of A / B / D / C is formed by laminating with a functional film (C) having at least one function among antifouling property, ultraviolet ray cut property, and near infrared ray cut property. And a process of
And a step of applying a pressure treatment to the laminated body.

  (2) A method for producing a display filter, wherein the visible light transmittance of the light-transmitting portion of the laminate is increased by 10% or more before and after the pressure treatment.

  (3) A method for producing a display filter, wherein the laminate is put into a pressurized container and held for 6 hours or less under a pressure of 0.2 MPa to 2 MPa.

  (4) The display filter, wherein the thickness of the conductive mesh layer (B) is d μm, and the thickness of the translucent adhesive material (D) is set in the range of (d−2) to (d + 30) μm. Manufacturing method.

  (5) The second functional film (C) is laminated on the transparent substrate (A) to form a laminate having a layer structure of C / A / B / D / C. Method for manufacturing a filter for an automobile.

  (6) A method for producing a display filter, wherein at least one layer of the laminate contains a pigment.

  (7) A method for producing a display filter, wherein a conductive portion for electrically connecting the conductive mesh layer (B) to an external ground is formed.

  (8) A method for producing a filter for a display, which is for a plasma display.

The top view which shows an example of the mesh pattern part 12 of the electroconductive mesh layer which concerns on this invention. Sectional drawing which shows an example of a structure of the filter for displays which concerns on this invention.

Explanation of symbols

10 Conductive mesh layer (B)
DESCRIPTION OF SYMBOLS 11 Conductive part 12 Mesh pattern part 13 Translucent adhesive 20 Transparent base | substrate (A)
21 Polymer Film 22 Translucent Adhesive Material 23 Glass 30 Translucent Adhesive Material Containing Dye (D)
40 Functional film (C)
41 Near-infrared absorber-containing layer 42 Antireflection layer having hard coat property, antistatic property and antifouling property 43 Polymer film 50 Functional film (C)
DESCRIPTION OF SYMBOLS 51 Adhesive material 52 Antireflection layer which has hard-coat property, antistatic property, and antifouling property 53 Polymer film

Claims (8)

A transparent substrate (A);
A conductive mesh layer (B) having a thickness of 5 to 15 μm, a mesh pattern portion having a line width of 5 to 20 μm, a pitch of 150 to 400 μm and a surface resistance of 3 Ω / □ or less, for shielding electromagnetic waves;
The thickness of the conductive mesh layer (B) is set to d μm, and the translucent adhesive material (D) having a thickness set in a range of d μm or more and less than (d + 30) μm,
A functional film (C) having at least one of a hard coat property, antireflection property, antiglare property, antistatic property, antifouling property, ultraviolet ray cut property, and near infrared ray cut property is bonded to Forming a laminate having a layer structure of / B / D / C;
The laminate is subjected to a pressure treatment that is held for 10 minutes to 6 hours under a pressure of 0.4 MPa to 2 MPa, and the visible light transmittance of the light-transmitting portion of the laminate is changed by 10% or more before and after the pressure treatment. And a process for increasing the display filter.   The second functional film (C) is bonded onto the transparent substrate (A) to form a laminate having a layer structure of C / A / B / D / C. Manufacturing method of display filter.   The method for producing a display filter according to claim 1 or 2, wherein at least one layer of the laminate contains a pigment.   The method for manufacturing a display filter according to any one of claims 1 to 3, wherein the conductive mesh layer (B) is formed with a conductive portion for electrical connection with an external ground.   It is an object for plasma displays, The manufacturing method of the filter for displays in any one of Claims 1-4 characterized by the above-mentioned. The transparent substrate (A) is composed of a transparent adhesive material (22) and a first polymer film (21),
The method for manufacturing a display filter according to claim 4, wherein the conductive portion (11) of the conductive mesh layer (B) is formed along a peripheral portion of the mesh pattern portion (12). The functional film (C) includes a near-infrared absorber-containing layer (41), a second polymer film (43), an antireflection layer (42) having hard coat properties, antistatic properties, and antifouling properties. The display filter manufacturing method according to claim 6, comprising:   A display filter obtained by the manufacturing method according to claim 1.

Images