JP2009016570A - Method for producing transparent electromagnetic shielding member - Google Patents

Abstract

A method for producing an electromagnetic wave shielding member having a high electromagnetic wave shielding property, which can be used on the front surface of a plasma display, etc., based on a mesh pattern obtained by printing using a conductive ink on a transparent substrate, and To provide an electromagnetic shielding member.
A method for manufacturing an electromagnetic shielding member in which a mesh pattern formed by two-dimensionally arranging line portions surrounding an opening portion in a plane by printing using a conductive ink on a transparent substrate is provided. Thus, there are a method for producing a transparent electromagnetic wave shielding member that performs induction heating treatment by applying a magnetic field in a direction perpendicular to the pattern printing surface, and an electromagnetic wave shielding member obtained by the production method.
[Selection figure] None

Description

  The present invention relates to a method for manufacturing a transparent electromagnetic wave shielding member disposed on the front surface of various displays.

In order to shield electromagnetic waves generated from various image display devices (displays) such as a PDP (plasma display panel) and a CRT (CRT) display, a substantially transparent electromagnetic wave shielding member is disposed on the front surface of the display.
Typical examples of such a substantially transparent electromagnetic wave shielding member include transparent conductive thin films made of sputtered thin films such as silver and ITO (indium tin oxide) (see Patent Document 1), highly conductive metal particles such as copper, and the like. There is a printed conductive ink pattern (see Patent Document 2) formed by printing a conductive ink (conductive paste) made of a binder resin to form a stripe (parallel line group). Of these, the sputtered silver thin film is expensive, and since it covers the entire surface, transparency increases when the film is thickened to increase electromagnetic wave shielding (conductivity), and thinned to increase transparency. Then, on the contrary, the electromagnetic wave shielding property (conductivity) is lowered, and the compatibility between transparency and electromagnetic wave shielding property is inferior.
On the other hand, since the printed conductive ink pattern has an opening, the transparency is high. However, since the electrically insulating binder resin blocks the contact between silver particles of a highly conductive material, there is a problem that the high conductivity inherent to silver is not exhibited.
Also, as a method for improving the decrease in the conductivity of the conductive ink itself due to the binder resin, a conductive ink composed of metal fine particles and a binder resin is applied on a transparent substrate to form a mesh pattern, followed by firing. This method has been used for a long time, and by firing, the binder resin, which is an insulator, is removed and the metal fine particles come into contact with each other. However, since high heat is applied to the transparent base material, it is limited to those using a glass substrate or a heat resistant film as a base material, and the cost is high.
In addition, in a method for improving conductivity by heating conductive ink, as a method for minimizing the influence of heat on the substrate, particles composed of a metal component and an organic component are mainly used on an insulator substrate. A method for producing a conductive coating (see Patent Document 3) is disclosed in which a conductive coating containing metal fine particles formed by applying and drying a metal colloid liquid is energized and sintered by its Joule heat. As an energization method, it is described that an induced current is applicable. However, in reality, this method is effective because a sufficient eddy current flows for a coating film formed with a solid surface (referring to a form covering the entire surface). However, as described above, since the entire surface is not transparent, the inventors of the present application have tried a prototype experiment, and as a result, when trying to apply to a transparent thin line pattern shape as shown in FIG. As described below, it has been found that there is a case where heating by an induced current cannot be performed in principle.
Here, induction heating will be briefly described with reference to FIG. In general, when heating a metal plate having a certain thickness, when a magnetic field parallel to the plate surface is applied as shown in FIG. 1 (a), an eddy current flows around the outer periphery of the cross section of the plate to generate heat. When the thickness of the metal plate is about several tens of μm, the currents flowing on the front and back of the plate cancel each other as shown in FIG. 1B, and heating becomes difficult. Therefore, when heating the metal foil, it is necessary to apply a magnetic field perpendicular to the foil surface as shown in FIG. 1C so that an eddy current flows in the surface of the foil. However, in the case where the conductive ink layer is formed in a thin and thin line like a parallel line group pattern for shielding transparent electromagnetic waves, as shown in FIG. It turned out that there was a problem.

JP-A-5-323101 Japanese Patent No. 3425400 JP 2004-79243 A

  An object of the present invention is to provide a method for producing an electromagnetic shielding member having high conductivity that can be used on the front surface of a plasma display, etc., based on a thin line pattern obtained by printing using a conductive ink on a transparent substrate.

When printing a substantially transparent pattern having a light transmission region composed of fine lines using a conductive ink on a transparent substrate, the present inventors have used a eddy current heating as a printing pattern. In order to form a closed circuit, the line portion surrounding the opening is a structural unit, and a mesh (mesh) structure in which the structural units are arranged in a two-dimensional direction makes it possible to generate eddy currents over the entire printed surface. Inductive heating is performed by applying an alternating magnetic field in a direction perpendicular to the mesh surface so that the ink flows in a uniform distribution, and the conductive ink is concentrated while minimizing the effect of heat on the transparent substrate. In addition, it is possible to heat the entire surface uniformly so that the metal particles are welded to each other at the contact portion, thereby reducing the electric resistance of the conductive material and improving the shielding property, that is, even if the conductive pattern line is thin when viewed microscopically. , Macroscopically and two-dimensionally If a single mesh-like conductive pattern is selected and an eddy current is allowed to flow in the mesh plane, even a mesh structure composed of lines with a line width of several μm to several tens of μm The inventors have found that induction heating is possible and completed the present invention.

That is, the present invention
(1) An electromagnetic shielding member manufacturing method in which a mesh pattern formed by two-dimensionally arranging line portions surrounding an opening portion in a plane by printing using a conductive ink on a transparent substrate is provided. A method of manufacturing a transparent electromagnetic wave shielding member, wherein induction heating treatment is performed by applying a magnetic field in a perpendicular direction to the pattern printing surface,
(2) The method for producing a transparent electromagnetic wave shielding member according to (1), wherein the conductive ink contains metal fine particles of gold, silver, copper, iron, nickel, or aluminum,
(3) On the transparent substrate, printing was performed using conductive ink having a solid content of 20 to 90 mass percent, in which 40 to 99 mass parts of metal fine particles were uniformly dispersed in 100 mass parts of solid content, and the solvent was dried. Thereafter, induction heating treatment is performed, the method for producing a transparent electromagnetic wave shielding member according to (2),
(4) The method for producing an electromagnetic wave shielding member according to any one of (1) to (3), wherein a base layer is present on at least a surface of the transparent substrate to be printed,
(5) Manufacture of the electromagnetic wave shielding member which has transparency in any one of said (1)-(4) which a transparent base material is a resin film, and lets it pass continuously with a roll-to-roll with respect to an induction heating apparatus. Method,
(6) The manufacturing method of the electromagnetic wave shielding member having transparency according to (5), wherein the transparent substrate is a polyethylene terephthalate film, and (7) the manufacturing method according to any one of (1) to (6). An electromagnetic shielding member having transparency obtained in
Is to provide.

By forming a mesh-like conductive pattern using conductive ink containing conductive particles on a transparent substrate, and reducing the electrical resistance by heat treatment by induction heating, transparency and electromagnetic wave shielding And both. In addition, since the production method of the present invention can be instantaneously heated, the preliminary time of the heating device is not required, and since the heat generation efficiency is high, the running cost in the heating process can be suppressed. In addition, since only the conductive ink layer is directly heated, the influence of heat on the transparent substrate can be minimized.

According to the method for producing a transparent electromagnetic shielding member of the present invention, a mesh pattern formed by two-dimensionally arranging line portions surrounding an opening portion in a plane is formed by printing using a conductive ink on a transparent substrate. In this method for producing an electromagnetic wave shielding transparent member, induction heating treatment is performed by applying a magnetic field in a direction perpendicular to the pattern printing surface.
Hereinafter, the present invention will be described in detail.

(Transparent substrate)
As the transparent substrate, a substrate transparent at least in the visible light region can be used. Polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylic such as polymethyl acrylate and polymethyl methacrylate A transparent sheet (or film) or transparent plate made of resin such as resin, polycarbonate (PC), polyimide (PI), or a transparent plate made of soda glass, potassium glass, borosilicate glass, lead glass, or the like can be used. .
As a printing method, a so-called transfer printing method is used in which a conductive pattern with reduced electrical resistance by induction heating is once formed on a releasable substrate and then transferred to another transparent substrate. In this case, the first releasable substrate does not necessarily need to be transparent, and if the heat resistance and releasability are good, a substrate suitable for transfer, such as a normal film or plate, can be used. is there.
Moreover, there may be an underlayer having various functions between the transparent substrate and the printed conductive paste. Examples of the various functions include adhesion improvement by easy adhesion primer coating treatment, durability improvement, printability improvement, heat resistance improvement, solvent resistance improvement and the like.
Furthermore, the transparent substrate preferably has a heat-resistant temperature as high as possible, but a suitable one may be selected in consideration of a necessary processing temperature, a cooling method to be used, costs, and the like.
For example, as a transparent substrate, polyethylene terephthalate (PET) is particularly recommended because of its excellent balance of transparency, mechanical strength, heat resistance, cost, and the like.
The thickness of the transparent substrate is not particularly limited as long as it depends on the application, but when it is made of a transparent resin sheet, it is usually about 10 to 500 μm and is a transparent resin plate or glass plate. In the case, about 1 to 5 mm is usually preferable.

[Conductive ink]
The conductive ink (sometimes referred to as conductive paste) used in the method for producing an electromagnetic wave shielding member of the present invention is obtained by uniformly dispersing conductive fine particles in a solution in which a binder resin is dissolved in a solvent. Is something.
A paste containing conductive particles such as a commercially available silver paste or copper paste can be used, and ink made of so-called nanometer-sized conductive particles that can be fired at a low temperature can also be used.
The conductive particles include gold, silver, platinum, copper, iron, nickel, tin, aluminum alone, or highly conductive metal fine particles or colloids made of an alloy containing these, non-conductive inorganic substances such as silica and alumina. A material in which the surface of the particle is coated with the metal, a material that develops conductivity by a chemical reaction by heating, or the like can be used.
It is preferable that the conductive material is developed to the extent that induction heating is possible immediately after the mesh pattern is formed by printing, but the conductive material may be developed by pretreatment such as electrochemical treatment or chemical treatment. Good. Moreover, you may combine these particle | grains suitably. The size of the particles should be small enough to be pasted (inked). Usually, a particle size of 100 μm or less is preferable, but it is preferably sufficiently smaller than the line width of the mesh pattern, and usually 10 μm or less. Is preferred. Also, the shape is not particularly limited, such as spherical, spheroid, polyhedral, lump, scale, disk, fiber or needle shape, and particles having various shapes, particle sizes, etc. are appropriately mixed and used. Also good. Note that the particle diameter is the maximum long diameter in the case of a spheroid, the diameter of a circumscribed sphere in the case of a polyhedron, or the maximum diagonal length in the case of a shape other than a sphere, or the longitudinal direction (long) in the case of a fibrous or needle shape. Axis length) etc. are evaluated.
When the conductive paste is used, the binder resin may be any resin that has adhesiveness to the conductive fine particles and the transparent substrate, such as an acrylic resin, a polyester resin, an ethylene-vinyl acetate copolymer resin, a urethane resin, and a phenol resin. An epoxy resin, a cellulose resin, or the like can be used.
The solvent is not particularly limited as long as it can dissolve the binder resin. In addition, when fine particles such as silver nanometer size particles are used, a dispersant or the like for suppressing aggregation is added.

The conductive ink used in the present invention is preferably a conductive ink having a solid content of 20 to 90 mass percent in which 40 to 99 mass parts of fine metal particles are uniformly dispersed in 100 mass parts of the solid content.
As the conductive ink (paste) used in the present invention as described above, a commercially available silver paste such as FA-333 (manufactured by Fujikura Kasei Co., Ltd.), ACP-051 (manufactured by Asahi Chemical Laboratory Co., Ltd.), etc. Commercially available copper paste can be used, but to adjust the coating suitability of the conductive ink, the shape and particle size of the conductive fine particles can be adjusted, the binder resin ratio can be adjusted, and the solid content can be adjusted. It is preferable to use it. In addition, these conductive inks include, for example, adjustment of ink coating suitability, improvement of ink stability, improvement of strength of conductive fine particle binders and improvement of adhesion to base materials, adjustment of voids of conductive fine particle binders, A filler (filler or extender pigment) or an additive may be added separately according to various purposes such as color adjustment of the conductive fine particle binder.
The filler can be selected from various shapes such as a spherical shape, a spheroid shape, a polyhedron shape, a truncated polyhedron shape, a lump shape, a scale shape, a disk shape, and a fiber shape. There is no restriction | limiting in particular about the viscosity of electroconductive ink, What is necessary is just to select suitably with the printing method and material to be used.

[Pattern shape]
Since the transparent electromagnetic wave shielding member of the present invention needs to ensure transparency while maintaining conductivity, the conductive ink layer is arranged with a fine line portion interposed between non-transparent non-forming portions. Form in a pattern. However, as described above, as described above, since heating due to eddy current does not effectively occur when the pattern is a group of parallel lines (stripes, stripes), the line portion surrounding the opening is used as a repeating unit. A closed circuit for eddy current is constructed. In addition, the repeating units (unit lattices) may be two-dimensionally arranged (for example, arranged in the vertical and horizontal directions) in a plane to form a mesh pattern shape that covers a desired region on the electromagnetic wave shielding member. With this arrangement, the eddy current flows at least uniformly or substantially uniformly over the entire area of the electromagnetic shielding member, and the conductive ink layer is heated substantially uniformly over the entire surface by the Joule heat of the eddy current. As the pattern shape, the shape of the opening is not particularly limited, and for example, a triangle such as a regular triangle, a square such as a square, a rectangle, a rhombus, a trapezoid, a polygon such as a hexagon, a circle, an ellipse, etc. There are two-dimensionally arranged patterns such as a lattice pattern, a honeycomb pattern, and a random mesh pattern.

In order to heat the conductive ink layer substantially uniformly over the entire surface, in addition to two-dimensionally arranging the unit cells constituting the closed circuit in a plane, the unit cell has a more isotropic shape. It is preferable to do. For example, in the case of a quadrangle, a square is preferable to a rectangle.
From the viewpoint of transparency, that is, light transmittance, it is preferable that the line width is narrower and the aperture ratio is larger.
On the other hand, from the viewpoint of the durability of the pattern, the development of high conductivity (high electromagnetic shielding properties), and the heating efficiency by eddy current, it is preferable that the line width is thick and the aperture ratio is small. In order to achieve both, it is preferable that the line width is 5 μm to 50 μm and the aperture ratio is 60 to 90%.
In order to allow the eddy current to flow uniformly, these patterns have anisotropy depending on the direction in the pattern printing surface as shown by arrows in FIG. 2A, for example, orthogonal coordinates as shown in the pattern surface. When the x-axis and y-axis of oxy are taken, it is necessary that the anisotropy such as line width, shape, period, etc. is small in the x-axis direction and the y-axis direction. This condition is satisfied if the line portion surrounding the opening is a repeating unit and is arranged in a two-dimensional direction (for example, the x-axis direction and the y-axis direction in FIG. 2A). In this way, when an alternating magnetic field is applied in the z-axis (perpendicular to the paper surface in FIG. 2) direction, a sufficient eddy current flows in the pattern surface, and the heating amount by the Joule heat increases. On the other hand, as shown schematically in FIG. 2 (c), even if it is a mesh pattern, if the opening is large, it is difficult for eddy currents to flow. It is preferable to do. In addition, the stripe pattern (parallel line group) shown in FIG. 2B is not formed with a closed circuit, and eddy current does not flow, so that induction heating is difficult.
Here, the pattern printing surface means a surface on which the pattern-printed conductive ink layer is placed and a surface parallel to the surface. When the distribution of the ink thickness (projection height of the pattern) of the conductive ink pattern can be ignored, it substantially matches the envelope surface on the surface of the conductive ink pattern. In FIG. 2, the xy plane corresponds to this. The pattern printing surface is usually a flat surface, but it may be a curved surface.

[Printing method]
The printing method for printing the conductive ink on the transparent substrate in a mesh pattern is not particularly limited, but is appropriately selected depending on the properties of the conductive ink.
When using fine metal particles with a nanometer size, the viscosity of the conductive ink is generally low, and ink jet printing, gravure printing, flexographic printing, etc. are suitable. When using fine metal particles with submicron to micron size, it is generally conductive. The viscosity of the reactive ink is high, and printing methods such as gravure printing, flexographic printing, silk screen printing, and dispensers are suitable. In addition, when the viscosity of conductive ink is low, you may provide a base layer in a base material so that the spreading of the pattern after printing may be suppressed.
After printing, for example, after drying with hot air at about 100 to 150 ° C. to volatilize the solvent, the printed metal is inserted through an induction heating device described later and heated by Joule heat of electromagnetic induction current (eddy current) The fine particles are fused. When the metal fine particles contained in the conductive ink are also ferromagnetic materials such as iron, in addition to heating by eddy current, by selecting a frequency that resonates with the natural frequency of the magnetic domain (magnetic efficiency) It is also possible to use heating due to magnetic domain hysteresis loss.
Alternatively, after the solvent is volatilized to some extent after printing, it is inserted into an induction heating device, and the residual solvent can be volatilized simultaneously while fusing the metal fine particles in the ink by heating with an electromagnetic induction current.

[Induction heating]
In the manufacturing method of the electromagnetic wave shielding member of the present invention, the thickness of the conductive layer by the printed conductive pattern is basically a thin object of about several tens of micrometers at maximum, so as shown in FIG. Therefore, a transverse type heating coil is used for induction heating. Note that the magnetic field transmitted through the pattern printing surface only needs to have a component that is orthogonal to the pattern printing surface to a practically sufficient level. Therefore, the magnetic field and the pattern printing surface do not necessarily have to be completely orthogonal.
The frequency and intensity of the alternating magnetic field to be applied are appropriately selected according to the material and pattern of the conductive ink to be used, the desired degree of heating, and the heating mode (eddy current heating, hysteresis loss heating). In addition, in order to prevent unnecessary heating of the transparent substrate, a frequency that does not induce heat generation due to dielectric loss of the substrate (dielectric material) is selected (usually, the frequency band of induction heating and dielectric heating is often different).
The frequency of the alternating magnetic field during induction heating is usually about 50 Hz to 1 MHz.
Only the conductive pattern itself generates heat during heating, but part of this heat is also conducted to the base material. Therefore, when thermal damage to the base material becomes a problem, the base material is appropriately cooled (heat radiation). . There is no particular restriction on the cooling method, and it is sufficient to cool by air cooling or contact with liquid / solid, but it is necessary not to be affected by or not affected by the magnetic field during induction heating. Not suitable for use. In addition, in order to heat uniformly, it is preferable to pass the base material to be heated through a magnetic field generated by a transverse heating coil at a constant speed by means such as roll-to-roll. The roll-to-roll referred to here is a material to be processed (in the present invention, a transparent base material, an electromagnetic wave shielding member, etc.) prepared in the form of a belt-like sheet and wound up on a roll (roll). A processing method of storing and transporting in a form, unwinding a belt-like sheet from the winding during processing, performing predetermined processing (in this invention, printing, induction heating, etc.), winding up again, transporting and storing To tell.
Moreover, in order to generate an induced current effectively, the surface resistance of the pattern before heating is preferably small, and is preferably 10Ω / □ or less. If the surface resistance is too high, the induced current is reduced and the heat generation efficiency is significantly reduced.

Since the method for producing an electromagnetic wave shielding member of the present invention causes the conductive pattern itself to generate heat by induction heating, thermal damage to the substrate can be reduced.
Furthermore, methods such as heating with energized Joule heat have the advantage of being able to heat in a short time, but it is difficult to make uniform contact between the terminals that supply large currents that generate heat and the printed surface of the conductive pattern. In particular, although it is difficult to perform continuous printing such as roll-to-roll, the manufacturing method of the present invention is non-contact heating by induction heating, and the conductive pattern has openings with less anisotropy in the x and y directions in the plane. Since a magnetic field perpendicular to the printing surface is applied to the pattern having the conductive pattern, the conductive pattern can be heated instantaneously.
Furthermore, it is not always necessary to raise the fusion temperature of the conductive material, and the conductivity can be improved even at a lower temperature. Although the detailed mechanism is unknown, the rearrangement of particles by melting and decomposition of the binder resin, etc. and the improvement of the contact property of the particles, the reduction of the contact resistance by removing the coating on the particle surface, the remaining in the binder resin It is conceivable that the particles become dense due to the drying of the residual solvent, or the micro fusion by the current concentrated at the contact point between the particles.
Furthermore, according to the manufacturing method of the present invention, only the conductive pattern on the substrate can be selectively heated instantaneously, and the damage to the substrate can be minimized by using it together with the cooling of the substrate. Can be suppressed. Of course, a heat resistant substrate may be used as the substrate, and after printing and heating a pattern on the heat resistant substrate, it may be transferred onto another transparent substrate using an adhesive or the like. .
In addition, if necessary, a known electrolytic plating or electroless plating is further performed on the electromagnetic wave shielding member whose conductivity is improved by induction heating, and the surface of the conductive ink printing pattern is obtained. On top of this, a highly conductive metal such as copper can be deposited to further improve the conductivity.
In addition, the electromagnetic wave shielding member according to the present invention may be laminated with other filter members such as an antireflection filter, a near infrared absorption filter, a colored filter, and an ultraviolet absorption filter, if necessary, in a display device such as a PDP. Can be installed on the front of the screen.

Hereinafter, the present invention will be described more specifically with reference to examples.
Example 1
A conductive ink (paste) composed of 92 parts by mass of silver particles having an average particle diameter of about 1 μm, 8 parts by mass of a polyester-based binder resin, and ethylene glycol monobutyl ether acetate as a solvent is prepared, and has a thickness of 100 mm and a size of 100 mm × 100 mm. A square lattice mesh pattern as shown in FIG. 2A having a line width of 30 μm, a pitch of 135 μm, a thickness of 25 μm and an aperture ratio of 60.5% is formed on a transparent substrate made of biaxially stretched PET. Formed. Next, this was dried with hot air at 150 ° C. to evaporate the solvent. This mesh-like electromagnetic wave shielding member is substantially transparent. When this is placed on a Bakelite heat sink and heated by induction using a transverse heating coil for 2 seconds under predetermined conditions, the color of the pattern portion instantly appears. The surface resistance was reduced by 42% compared with the electromagnetic wave shielding member before induction heating, and was 0.3Ω / □.

Example 2
In place of the conductive ink (paste) of Example 1, silver nanopaste containing silver particles having an average particle size of 50 nm or less was used, and an ink jet printing method was used on a transparent substrate made of a polyimide sheet having a thickness of 75 μm. A honeycomb-shaped (turtle shell lattice) mesh pattern having a line width of 30 μm, a side of 100 μm, and an aperture ratio of 60.0% was printed. When this base material was induction-heated with a transverse type heating coil for 1 second under predetermined conditions, the pattern portion was instantly discolored, and the volume resistivity of the pattern portion was on the order of 10 ⁻⁶ Ω · cm.

Comparative Example 1
A transparent sheet was formed in the same manner as in Example 1 except that a stripe pattern consisting of parallel line groups having a line width of 30 μm and a pitch of 75 μm running only in the y direction as shown in FIG. Created. Subsequently, when this stripe pattern transparent base material was induction-heated in the same manner as in Example 1, it could not be heated at all. Therefore, the surface resistance could not be reduced.

  In the method for producing an electromagnetic wave shielding member of the present invention, a conductive ink is directly printed on a transparent substrate, and then the conductive pattern is heated by induction heating to fuse the conductive particles. An electromagnetic shielding member with reduced surface resistance can be obtained while reducing thermal damage to the surface, and can be effectively used as a method for producing an electromagnetic shielding member having transparency and disposed on the front surface of various displays, and as an electromagnetic shielding member. .

It is explanatory drawing of the relationship between the direction of the magnetic field with respect to a metal plate, and an eddy current. (A) Side surface of normal thickness metal plate, (b) Side surface of thin metal plate, (c) Vertical surface of thin metal plate, (d) Vertical surface of circuit wiring with narrow line width. It is explanatory drawing at the time of applying a magnetic field perpendicularly | vertically to the printing surface of various mesh patterns from which a shape differs. (A) An example of a uniform mesh pattern in which a mesh pattern is a uniform mesh pattern in which unit cells of a closed circuit surrounded by a line portion are periodically arranged in the x and y directions, and (b) a stripe in which straight portions are arranged only in the x direction. (C) An example of a square lattice, but the aperture ratio is too large and the density of the conductive portion is low.

Claims (7)

  A method for producing an electromagnetic wave shielding member in which a mesh pattern formed by two-dimensionally arranging line portions surrounding an opening portion in a plane by printing using a conductive ink on a transparent substrate, the pattern A method for producing a transparent electromagnetic wave shielding member, wherein induction heat treatment is performed by applying a magnetic field in a perpendicular direction to a printed surface.   The method for producing a transparent electromagnetic wave shielding member according to claim 1, wherein the conductive ink contains metal fine particles of gold, silver, copper, iron, nickel, or aluminum.   On a transparent base material, printing is performed using conductive ink having a solid content of 20 to 90 mass percent, in which 40 to 99 mass parts of metal fine particles are uniformly dispersed in 100 mass parts of solid content, and after the solvent is dried, induction is performed. The method for producing a transparent electromagnetic wave shielding member according to claim 2, wherein heat treatment is performed.   The manufacturing method of the electromagnetic wave shielding member which has transparency in any one of Claims 1-3 in which the base layer exists in the surface at the side by which the transparent base material is printed at least.   The manufacturing method of the electromagnetic wave shielding member which has transparency in any one of Claims 1-4 which a transparent base material is a resin film, and lets it pass continuously with a roll toe roll with respect to an induction heating apparatus.   The method for producing a transparent electromagnetic wave shielding member according to claim 5, wherein the transparent substrate is a polyethylene terephthalate film. The electromagnetic wave shielding member which has the transparency obtained with the manufacturing method in any one of Claims 1-6.

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