JP2009200312A - Electromagnetic shielding material, its manufacturing method, and filter for display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic shielding material that can increase contrast by using a louver-like protruding pattern for reducing an effect of outside light, a method of manufacturing the electromagnetic shielding material, and a filter for a display that has the electromagnetic shielding material. <P>SOLUTION: An electromagnetic shielding material 10 comprises: a transparent base material 1; a primer layer 2 formed on the transparent base material 1; and a protruding pattern 19 formed in a predetermined pattern on the primer layer 2 and at least including a conductive layer 3. In the primer layer 2, a portion A with the conductive layer 3 has a thickness T<SB>A</SB>larger than the thickness T<SB>B</SB>of a portion B without the conductive layer 3. The cross-sectional area obtained by being cut along a virtual plane parallel to the surface of the transparent base material in the conductive layer 3 constituting the protruding pattern 19 has a decreasing function S(x) of the distance x from the transparent base material 1. In addition, at least side surfaces of the protruding pattern 19 are subjected to blackening treatment. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electromagnetic wave shielding material, a manufacturing method thereof, and a display filter, which can increase the contrast by reducing the influence of external light by a louver-like protruding pattern.

  Examples of display devices (image display devices) such as monitors for televisions and personal computers include cathode ray tube (CRT) display devices, liquid crystal display devices (LCD), plasma display devices (PDP), and electroluminescence (EL) display devices. Are known. Among these display devices, plasma display devices that are attracting attention in the field of large-screen display devices use plasma discharge for light emission. Therefore, unnecessary electromagnetic waves in the 30 MHz to 1 GHz band leak to the outside and other devices ( For example, remote control devices, information processing apparatuses, etc.) may be affected. Therefore, it is common to provide a film-like electromagnetic shielding material for shielding electromagnetic waves that leak from the front side (observer side) of the plasma display panel used in the plasma display device.

Various electromagnetic shielding materials have been studied so far. For example, in Patent Document 1, an electroless plating catalyst paste is silk-screen printed in a mesh pattern on a transparent substrate, and a metal layer is electrolessly plated thereon. An electromagnetic shielding material in which a protruding pattern is formed has been proposed. Patent Document 2 discloses that a conductive ink composition is intaglio offset printed on a transfer body in a mesh pattern, the mesh pattern on the transfer body is transferred onto a transparent substrate, and a metal layer is formed on the mesh pattern on the transparent substrate. An electromagnetic shielding material in which a protruding pattern is formed by electroplating is proposed. Patent Document 3 discloses an electromagnetic wave shielding material in which a conductive ink composition is directly intaglio-printed on a transparent substrate in a mesh pattern, and a metal layer is electroplated on the mesh pattern on the transparent substrate to form a protruding pattern. Has been proposed.
JP 11-170420 A JP 2001-102792 A Japanese Patent Laid-Open No. 11-174174

  However, since the conventional protruding pattern obtained by the method described in each of the above documents cannot increase the cross-sectional height (cross-sectional height / line width) with respect to the line width, it is used as a louver that reduces the influence of external light. However, the effect of improving contrast was hardly expected.

  Specifically, the electromagnetic wave shielding material described in Patent Document 1 forms a mesh pattern by silk screen printing, which is difficult to form a fine pattern, and forms a metal layer by electroless plating with a slow film formation speed and a large amount of sag due to flow. Since the protrusion pattern is provided, the [section height / line width] ratio cannot be sufficiently increased. The electromagnetic shielding material described in Patent Document 2 forms a mesh pattern by intaglio printing, so that a fine pattern can be formed. However, since an offset method is employed, the transfer body is once transferred from the intaglio to the transfer body. To the second transfer to the transparent substrate. Therefore, the original intaglio mesh pattern may not be faithfully transferred to the transparent substrate. As a result, even when the metal layer is electroplated on the mesh pattern, the cross-sectional height of the protruding pattern is not constant. The [height / line width] ratio cannot be made uniform and large. Furthermore, the electromagnetic wave shielding materials described in Patent Documents 2 and 3 have untransferred portions or transfer defects inferior in adhesiveness when transferred (also referred to as transfer) from an intaglio to a transfer body or transparent substrate. In some cases, the [section height / line width] ratio cannot be sufficiently increased, and a protruding pattern cannot be stably formed in the first place. More specifically, as shown in FIG. 15, when the conductive ink composition 103 is applied on the intaglio plate 101 and scraped with a doctor blade 102 to fill the concave ink 104 with the conductive ink composition 103, FIG. As shown in FIG. 15 (B), the conductive ink composition 103 in the recess 104 after scraping with the doctor blade 102 has a recess 105 in the upper part thereof. As shown in FIG. 15C, the dent 105 is then formed when the transparent base 106 is pressure-bonded onto the intaglio 101 and the conductive ink composition 103 in the recess 104 is transferred onto the transparent base 106. This is a factor that hinders adhesion between the transparent substrate 106 and the conductive ink composition 103. As a result, an untransferred portion of the conductive ink composition occurs on the transparent substrate 106, or a transfer failure that is inferior in adhesiveness occurs, so that the protruding pattern cannot be stably formed.

  In addition to this, when printing a high viscosity or low fluidity ink composition such as a conductive ink composition on an intaglio plate having a large [section height / line width] ratio, The ink composition filled in the ink composition does not transfer to the transparent substrate but remains in the recesses of the plate. That is, the transfer rate of the ink filled in the concave portion of the plate (ratio of [the amount of ink transferred onto the transparent substrate / the amount of ink filled in the concave portion of the plate]) becomes low. This phenomenon also causes a reduction in the reproducibility of the intaglio shape and the amount of the conductive ink composition to be transferred.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to transfer an electroconductive composition onto a transparent substrate by intaglio printing to form an electroconductive protruding pattern. An object of the present invention is to provide an electromagnetic wave shielding material and a display filter provided with the electromagnetic wave shielding material, which can reduce the influence of external light by a louver-like protruding pattern and increase the contrast.

  Another object of the present invention is to provide a method of manufacturing an electromagnetic wave shielding material that can form a louver-like protruding pattern with good shape reproducibility, and can reduce the influence of external light by the protruding pattern and increase contrast. There is to do.

  Recently, we have developed an electromagnetic shielding material by intaglio printing method using a fluid primer and a method for producing the same, and have already filed applications (Japanese Patent Application No. 2007-299468, etc.). According to this invention, it is possible to transfer the conductive composition filled in the recesses on the surface of the intaglio onto the substrate with high shape reproducibility and transfer rate. As a result, a mesh-shaped protruding pattern having a desired shape can be stably formed, and the [section height / line width] ratio of the protruding pattern can be increased, and further, the function as a louver. Can be granted. The present invention has been completed based on such development progress.

  That is, the electromagnetic wave shielding material of the present invention for solving the above problems includes a transparent substrate, a primer layer formed on the transparent substrate, and a conductive composition formed in a predetermined pattern on the primer layer. A projecting pattern including at least a conductive layer made of a material, and a thickness of a portion of the primer layer where the conductive layer is formed is a thickness of a portion where the conductive layer is not formed The cross-sectional area of the conductive layer that is thicker than that and cut in a virtual plane parallel to the surface of the transparent substrate is the decreasing function S (x) of the distance x from the transparent substrate, In addition, at least the outermost surface of the protruding pattern is blackened.

  According to this invention, the protruding pattern has a cross-sectional area cut along a virtual plane parallel to the transparent substrate surface, which is a decreasing function S (x) of the distance x from the transparent substrate, and the protruding pattern Since at least the outermost surface of the side surface is blackened, the protruding pattern can function as a louver that blocks external light (hereinafter abbreviated as external light). As a result, the influence of external light can be reduced and the contrast can be increased.

  Furthermore, according to the present invention, the thickness of the portion where the conductive layer is formed in the primer layer provided on the transparent substrate is thicker than the thickness of the portion where the conductive layer is not formed. A primer layer is provided to fill the indicated recess. The primer layer having such a form is formed by filling the recess of the upper part of the conductive composition in the recess of the shaping plate surface after scraping with a doctor blade during the production of the electromagnetic shielding material, and as a result. Thus, an electromagnetic wave shielding material can be provided in which the primer layer adheres closely to the conductive composition without voids and does not cause defects such as disconnection, shape failure, and low adhesion due to poor transfer of the conductive composition. In addition, according to the present invention, since the conductive layer is provided with improved transferability of the conductive composition, the thickness of the conductive composition after the transfer is compared with a method using intaglio such as normal gravure printing. As a result, the conductive layer can be thickened, and the conductivity required for the electromagnetic wave shielding material can be ensured. This is because the conductive composition filled in the recesses on the surface of the intaglio can be transferred as a conductive layer on the base material with high shape reproducibility. As a result, it becomes possible to stably form a mesh-like projecting pattern having a desired shape, and as a result, it is possible to increase the [section height / line width] ratio of the projecting pattern and to provide a function as a louver. It becomes possible.

As a preferable aspect of the electromagnetic wave shielding material of the present invention, when the line width of the protruding pattern is W, the pitch (line interval) of the protruding pattern is L, and the height of the protruding pattern is H, θ = tan ^−1. The angle θ indicated by (((L−W) / 2 + (W / 2)) / H) is configured to be less than 87 °. Here, the height H is represented by a difference in thickness between the protruding pattern forming portion and the protruding pattern non-forming portion. According to the present invention, since θ represented by the above relational expression is less than 87 °, the shadow caused by the protruding pattern covers half of the opening, so that the contrast can be increased.

  As a preferable aspect of the electromagnetic wave shielding material of the present invention, the ratio (W / L) between the line width W of the protruding pattern and the pitch L of the protruding pattern is configured to be less than 0.15. According to the present invention, since the line width is small with respect to the pitch of the protruding pattern, it is possible to maintain a high aperture ratio above a certain level, and it is possible to increase the contrast while preventing a decrease in transmittance.

  In the electromagnetic wave shielding material of the present invention, the protruding pattern may be configured to include a metal layer formed on the surface of the conductive layer.

  In the electromagnetic wave shielding material of the present invention, the primer layer is preferably a layer made of an ionizing radiation curable resin or a thermoplastic resin. Here, the ionizing radiation curable resin is a resin having a property of being cured by irradiation with ionizing radiation such as ultraviolet rays or electron beams.

  In the electromagnetic wave shielding material of the present invention, the resin contained in the conductive layer is preferably a thermoplastic resin, an ionizing radiation curable resin, or a thermosetting resin.

  In the electromagnetic wave shielding material of the present invention, as a preferred first form, the interface between the primer layer and the conductive layer is an interface between the resin constituting the primer layer and the resin or powder constituting the conductive layer. And are configured to be interlaced alternately. As a preferred second embodiment, a region where the primer component contained in the primer layer and the conductive composition are mixed is present in the vicinity of the interface between the primer layer and the conductive layer. Moreover, as a preferable third embodiment, the primer composition contained in the primer layer is present in the conductive composition constituting the conductive layer. Moreover, as a preferable fourth embodiment, the protruding pattern includes a first peak made of the primer layer, and a second peak made of the conductive composition formed above the middle of the first peak. It is configured to be a pattern composed of

  According to the first to third aspects of the invention, since the interface between the primer layer on the transparent substrate and the conductive layer formed in a pattern is not a simple boundary surface structure, the adhesion between both layers In addition, when the electromagnetic wave shielding material is manufactured, the transfer (transfer) of the conductive composition filled in the plate surface to the transparent substrate is reliably performed under a high transfer rate. Further, according to the fourth aspect of the invention, the conductive layer is composed of a projecting pattern composed of the first mountain and the second mountain formed above the middle of the first mountain. The conductive composition constituting the second peak is less likely to drop off from the primer layer constituting the first peak, and the transparent base of the conductive composition filled in the plate surface during the production of the electromagnetic wave shielding material. Transfer (transfer) to the material is reliably performed under a high transfer rate.

  The display filter of the present invention for solving the above-mentioned problems has the electromagnetic wave shielding material according to the present invention and is provided on the front side of the display. According to this invention, since the electromagnetic wave shielding material formed with the protruding pattern that functions as a louver that blocks outside light is provided, it is possible to provide a display filter that reduces the influence of outside light and increases the contrast.

The first aspect of the method for producing an electromagnetic wave shielding material according to the present invention for solving the above problems is an electromagnetic wave shielding material having a protruding pattern including at least a conductive layer formed in a predetermined pattern on one surface of a transparent substrate. A transparent substrate preparing step of preparing a transparent substrate having a primer layer formed on one surface capable of maintaining fluidity until cured, and a plate surface having a concave portion having a predetermined pattern is formed. In addition, a plate-like or cylindrical plate is prepared in which the opening cross-sectional area of the recess cut by a virtual plane parallel to the surface of the plate surface is a decreasing function S (x) of the distance x from the surface. An intaglio plate preparation step, and after applying a conductive composition capable of forming a conductive layer after curing on the plate surface, the conductive composition adhering to a portion other than the inside of the concave portion is scraped off and the conductive composition is put into the concave portion. Filling the conductive Bonding the primer layer side of the transparent base material after the composition filling step and the transparent base material preparation step and the concave side of the plate surface after the conductive composition filling step, the conductivity in the primer layer and the concave portion A pressure-bonding step for closely adhering the conductive composition without gaps, a primer layer curing step for curing the primer layer after the pressure-bonding step but not completely curing the conductive composition, and the transparent group after the primer-layer curing step. A transfer step of peeling the material and the primer layer from the plate surface and transferring the conductive composition in the concave portion onto the primer layer; and after the transfer step, a conductive pattern formed on the primer layer in a predetermined pattern A conductive composition curing step of curing the composition to form a conductive layer, and the protruding pattern is formed by blackening at least the outermost surface of the side surface. The width W, the pitch of the protruding pattern (line spacing) L, the height of the protruding pattern is taken as ^{H, θ = tan -1 ((} (L-W) / 2 + (W / 2)) / The angle θ indicated by H) is less than 87 °.

  In the method for producing an electromagnetic wave shielding material according to the first aspect, the conductive composition in the conductive composition filling step is a composition capable of forming a conductive layer that can be electroplated after curing, and the conductive composition You may comprise so that it may further have the plating process of carrying out the electrolytic plating of a metal layer on the conductive layer formed in the predetermined pattern on the said primer layer after an object hardening process.

The second aspect of the method for producing an electromagnetic shielding material of the present invention is a method for producing an electromagnetic shielding material having a protruding pattern including at least a conductive layer formed in a predetermined pattern on one surface of a transparent substrate. A transparent base material preparation step for preparing a transparent base material having a primer layer formed on one side thereof that can maintain fluidity until it is cured, and a plate surface having a concave portion having a predetermined pattern, and the plate surface An intaglio plate preparation step for preparing a plate-shaped or cylindrical plate, in which the opening cross-sectional area of the recess cut by a virtual plane parallel to the surface of the plate is a decreasing function S (x) of the distance x from the surface; After applying a conductive composition capable of forming a conductive layer after curing on the plate surface, the conductive composition adhering to other than the inside of the concave portion is scraped to fill the concave portion with the conductive composition. Product filling process and before The primer layer side of the transparent substrate after the transparent substrate preparation step and the concave side of the plate surface after the conductive composition filling step are pressure-bonded so that the primer layer and the conductive composition in the concave portion are free from voids. A pressure-bonding step that adheres, a simultaneous curing step of simultaneously curing the primer layer and the conductive composition after the pressure-bonding step, and peeling the transparent substrate and the primer layer from the plate surface after the simultaneous curing step. A transfer step of transferring the conductive composition as a conductive layer onto the primer layer, and the protruding pattern is formed by blackening at least the outermost surface of the side surface, and the line width of the protruding pattern is W, Θ = tan ⁻¹ (((L−W) / 2 + (W / 2)) / H) where L is the pitch (line interval) of the protruding pattern and H is the height of the protruding pattern. Angle θ is less than 87 ° It is characterized by that.

  In the method for producing an electromagnetic wave shielding material according to the second aspect, the conductive composition in the conductive composition filling step is a composition capable of forming a conductive layer that can be electroplated after curing, and after the transfer step. In addition, it may be configured to further include a plating step of electroplating a metal layer on a conductive layer formed in a predetermined pattern on the primer layer.

  According to the first and second aspects of the invention, the primer layer side of the transparent base material on which the primer layer retaining fluidity is formed and the concave side of the plate surface after the conductive composition filling step are pressure-bonded. Therefore, the flowable primer layer is filled in the recess that is likely to be formed on the conductive composition in the recess. As a result, the primer layer adheres to the conductive composition without voids, so that the conductive composition in the recess can be accurately transferred without any untransferred portion on the transparent substrate side. Thus, it is possible to produce an electromagnetic shielding material that does not cause defects such as disconnection, shape failure, and low adhesion due to poor transfer of the conductive composition. Furthermore, since it is possible to transfer the conductive composition filled in the recesses on the surface of the intaglio plate as a conductive layer on the base material with high shape reproducibility, if blackening treatment or the like is performed on the conductive layer, it is desirable A mesh-like protruding pattern consisting of shapes can be formed stably, and as a result, the ratio of the [section height / line width] of the protruding pattern can be increased, and the function as a louver for increasing the contrast. Can be given.

  In the method for producing an electromagnetic wave shielding material according to the first and second aspects of the present invention, the primer layer is a layer made of an ionizing radiation curable resin or a thermoplastic resin, and the fluidity of the primer layer is maintained by ionizing radiation. It is preferable to carry out by non-irradiation or heating.

  In the method for producing an electromagnetic wave shielding material according to the first and second aspects of the present invention, the conductive composition contains a conductive powder and a resin, and the resin is a thermoplastic resin, an ionizing radiation curable resin, or a thermosetting. A resin is preferred. The conductive composition includes a solvent that dissolves the resin as necessary, and is a composition that can form a conductive layer by a curing means such as drying or ionizing radiation irradiation, and the plate surface in the conductive composition filling step It is preferable to have fluidity that can be filled in the recesses.

  In the method for manufacturing an electromagnetic wave shielding material according to the first and second aspects of the present invention, the thickness of the portion of the primer layer to which the conductive composition is transferred after the transfer step is the conductive composition. It is preferable that the thickness is larger than the thickness of the portion where the toner is not transferred. According to the production method of the present invention, by pressing the primer layer side of the transparent substrate on which the primer layer retaining fluidity is formed and the concave side of the plate surface after the conductive composition filling step, Since the primer layer with fluidity is filled in the dent that is likely to be formed on the upper part of the conductive composition, and then the primer layer is cured, the finally obtained form is the primer layer provided on the transparent substrate. The thickness of the portion where the conductive layer is formed is thicker than the thickness of the portion where the conductive layer is not formed (that is, a biting shape). Since the obtained electromagnetic shielding material has such a form, problems such as disconnection, shape failure, and low adhesion due to poor transfer of the conductive layer do not occur.

  According to the electromagnetic wave shielding material of the present invention, since the protruding pattern functions as a louver that blocks outside light, the influence of outside light can be reduced and the contrast can be increased. Furthermore, since the primer layer is provided so as to fill the dent pointed out in the above problem, an electromagnetic wave shielding material that does not cause defects such as disconnection, shape defect, and low adhesion due to poor transfer of the conductive layer is provided. Can do. In addition, the adhesion between the primer layer and the conductive layer has been improved, and the transfer (transfer) of the conductive composition filled in the plate surface to the transparent substrate during the production of the electromagnetic wave shielding material is high. Certainly done at a rate. This is because the conductive composition filled in the recesses on the surface of the intaglio can be transferred as a conductive layer on the base material with high shape reproducibility. As a result, it becomes possible to stably form a mesh-like projecting pattern having a desired shape, and as a result, it is possible to increase the [section height / line width] ratio of the projecting pattern and to provide a function as a louver. It becomes possible.

  Furthermore, according to the electromagnetic wave shielding material of the present invention, since the protruding pattern having the shape represented by the above relational expression is provided, the contrast can be increased, and the contrast can be increased in a state where the transmittance is prevented from being lowered. it can.

  According to the display filter of the present invention, since the electromagnetic wave shielding material formed with the protruding pattern that functions as a louver that blocks outside light is provided, it is possible to provide a display filter that reduces the influence of outside light and increases the contrast. .

  According to the method for producing an electromagnetic wave shielding material of the present invention, as a first effect, since the conductive composition in the recess can be accurately transferred without any untransferred portion on the transparent substrate side, It is possible to manufacture an electromagnetic shielding material that does not cause defects such as disconnection, shape failure, and low adhesion due to poor transfer of the conductive composition. Furthermore, as a second effect, it is possible to transfer the conductive composition filled in the concave portion of the intaglio surface as a conductive layer on the substrate with high shape reproducibility by the first effect. As a result, it becomes possible to stably form a mesh-like protruding pattern having a desired shape, and as a result, it is possible to increase the [section height / line width] ratio of the protruding pattern, and as a louver for increasing contrast. Functions can be added.

  Next, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.

[Electromagnetic wave shielding material]
FIG. 1 is a schematic plan view showing an example of the electromagnetic wave shielding material of the present invention, and FIG. 2 is an enlarged view of the AA ′ cross section in FIG. FIG. 3 is a schematic cross-sectional view showing a part of FIG. 2 further enlarged, (A) is an example in which a metal layer is not provided on the conductive layer, and (B) is on the conductive layer. This is an example in which a metal layer is provided. An electromagnetic wave shielding material 10 according to the present invention includes a protruding pattern 19 including at least a transparent substrate 1, a primer layer 2 formed on the transparent substrate 1, and a conductive layer 3 formed in a predetermined pattern on the primer layer 2. And have. Then, as shown in FIG. 3, of the primer layer 2, the thickness T _A of the portion A conductive layer 3 is formed is thicker than the thickness T _B of the portion B of the conductive layer 3 is not formed, Further, as shown in FIG. 4, the cross-sectional area of the protruding pattern 19 cut by a virtual plane parallel to the transparent substrate surface is a decreasing function S (x) of the distance x from the transparent substrate 1, and At least the outermost surface of the protruding pattern 19 is blackened. Further, as shown in FIGS. 7 and 8, the preferred embodiment of the electromagnetic wave shielding material 10 of the present invention is such that the line width of the protruding pattern 19 is W, the pitch (line interval) of the protruding pattern 19 is L, and the protruding pattern 19 is high. When the height is H, an imaginary line extending from an arbitrary point (for example, the center point Q) of the opening toward the top of the protruding pattern 19 is a line S1 in contact with the protruding pattern 19, and a normal line of the electromagnetic wave shielding material 10 The angle θ with S2 is less than a predetermined value.

  Here, the line width W refers to the height H direction and the longitudinal direction in a cross-sectional shape in which at least the outermost surface of the side surface is cut by a cross section (zx plane in FIG. 4) perpendicular to the longitudinal direction of the shape. This is the width in the direction orthogonal to the direction (z direction in FIG. 4). And as above-mentioned, as for the protrusion pattern 19 in this invention, the cross-sectional area which cut | disconnected the protrusion pattern in the virtual surface parallel to the said transparent base material surface is also the distance x (height H direction distance) from this transparent base material. ) Decrease function S (x). Therefore, the width of the protruding pattern 19 itself is also a decreasing function in the distance x or height H direction. In the present invention, the line width W is defined as the width of the portion of the protruding pattern 19 that is closest to the transparent substrate 1 (also referred to as the maximum width of the protruding pattern).

  Further, “including at least the conductive layer 3” means that the conductive layer is formed regardless of whether or not the metal layer 4 is formed as a layer constituting the protruding pattern 19 as shown in FIGS. 3 is formed. The “predetermined pattern” is a pattern such as a mesh (net or lattice) shape, a stripe (parallel line group or stripe pattern), or a line segment group, which is a general electromagnetic wave shielding pattern of the electromagnetic wave shielding material 10. . In FIG. 1, reference numeral 7 is an electromagnetic shielding pattern portion located at the center and facing the image display area of the display device, and reference numeral 8 is present at least at a part of the peripheral edge of the electromagnetic shielding pattern portion. It is a grounding part. In the grounding portion 8, the grounding ability is preferably as shown in FIG. 1 so as to surround the entire periphery of the peripheral portion of the electromagnetic wave shielding pattern portion 7. Further, the grounding portion 8 may be formed in a pattern having openings such as meshes, but more preferably, as shown in FIG. Conductive layer and metal layer). In the present invention, the grounding portion 8 as shown in FIG. 1 does not have to exist in the peripheral portion, and the whole can be formed into a seamless mesh shape. In this case, continuous formation is possible regardless of the size of the display. Moreover, as shown in FIG. 2, a protective layer 9 (for example, an acrylic photocurable resin layer) may be formed as necessary.

  Hereinafter, the configuration of the present invention will be described in detail.

(Transparent substrate)
The transparent base material 1 is a base material for the electromagnetic wave shielding material 10 and has various thicknesses of various materials in consideration of required transparency such as desired transparency, mechanical strength, adhesiveness with the primer layer 2, and the like. Just choose. The material of the transparent substrate 1 may be a resin substrate or an inorganic substrate such as a glass substrate. Further, the thickness form may be film, sheet or plate. Usually, a resin transparent film is preferably used. As such a transparent film, a film based on an acrylic resin (used here as a concept including a methacrylic resin), a polyester resin, or the like is preferable, but is not limited thereto. Specific resin materials used for the film include cellulose resins such as triacetyl cellulose, diacetyl cellulose, and acetate butyrate cellulose, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), ethylene glycol-terephthalic acid-isophthalate. Acid copolymer, terephthalic acid-ethylene glycol-1,4 cyclohexane dimethanol copolymer, polyester resin such as polyester thermoplastic elastomer, polyolefin resin such as polyethylene, polypropylene, polymethylpentene, cyclic polyolefin, polyvinyl chloride, Halogen-containing resins such as polyvinylidene chloride, polyethersulfone resins, polyacrylic resins, polyurethane resins, polycarbonate resins, styrene resins such as polystyrene Fat, polyamide resins, polyimide resins, polysulfone resins, polyether resins, polyether ketone, (meth) acrylonitrile and the like can be used. Among them, the biaxially stretched PET film is preferable in that it has excellent transparency and durability, and has heat resistance that does not cause thermal deformation even when subjected to ultraviolet irradiation treatment or heat treatment in the subsequent steps. Here, (meth) acryl means acryl or methacryl.

  Further, as the material used for the plate, as the resin, the resin exemplified in the resin film can be used, and as the inorganic material, glass such as soda glass, potassium glass, borosilicate glass, or the like can be used.

  The transparent substrate 1 may be a long film of rolls, tows, or rolls, or may be a sheet film having a predetermined size. Here, the term “roll toe roll” means that a long belt-like base material is supplied in the form of a roll (roll), and the belt-like sheet is unwound from the roll to perform a predetermined process, and thereafter It means a form of use of the film that is wound up, stored and transported again in the form of winding. The thickness of the transparent substrate 1 is usually preferably about 8 μm to 1000 μm, and in the case of a plate, preferably about 500 μm to 5000 μm, but is not limited thereto. The light transmittance of the transparent substrate 1 is ideally 100% for installation on the front surface of the display device, but it is preferable to select a light transmittance of 80% or more. If necessary, an easy-adhesion layer is provided on the surface of the transparent substrate 1 to improve the adhesion between the primer layer 2 and the transparent substrate 1, which will be described later, or corona discharge treatment, plasma treatment, flame treatment, etc. The surface treatment may be performed. As an easily bonding layer, it comprises from resin which has adhesiveness in both the transparent base material 1 and the primer layer 2. FIG. The resin of the easy adhesion layer is appropriately selected from resins such as urethane resin, epoxy resin, polyester resin, acrylic resin, and chlorinated polypropylene.

(Primer layer)
The primer layer 2 is provided on the transparent substrate 1 with good adhesion. A conductive layer 3 is provided on the primer layer 2 with good adhesion. Therefore, the primer layer 2 is preferably a material having good adhesion to both the transparent base material 1 and the conductive layer 3 and, of course, for the installation of the front surface of the display device, it is of course against visible light. And transparent. For example, a layer formed by applying an ionizing radiation curable resin or a thermoplastic resin is preferable. Various additives and modified resins may be used to improve adhesion, durability, and impart various physical properties.

  Examples of the thermoplastic resin include acrylic resins such as polymethyl methacrylate (PMMA), vinyl chloride-vinyl acetate copolymers, polyester resins, and polyolefin resins.

  As the ionizing radiation curable resin, a monomer (monomer) that is polymerized and cured by a reaction such as crosslinking with ionizing radiation, or a prepolymer or an oligomer is used. Examples of the monomer include radically polymerizable monomers, specifically 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate and the like (meta ) Acrylates. Examples of the prepolymer (or oligomer) include radically polymerizable prepolymers, specifically, various (meth) acrylate prepolymers such as urethane (meth) acrylate, epoxy (meth) acrylate, and polyester (meth) acrylate. Examples thereof include polymers and unsaturated polyester prepolymers. Other examples include cationically polymerizable prepolymers such as novolac epoxy resin prepolymers and aromatic vinyl ether resin prepolymers. Here, the notation (meth) acrylate means acrylate or methacrylate.

  These monomers or prepolymers may be used alone or in combination of two or more types of monomers, two or more types of prepolymers, or one type of monomer, depending on the required performance, coating suitability, etc. A mixture of the above and one or more prepolymers can be used.

  As the photopolymerization initiator, in the case of a radical polymerizable monomer or prepolymer, a compound such as benzophenone, thioxanthone, or benzoin is used, and in the case of a cationic polymerization monomer or prepolymer, a metallocene is used. , Aromatic sulfonium-based and aromatic iodonium-based compounds are used. These photopolymerization initiators are added in an amount of about 0.1 to 5 parts by weight with respect to 100 parts by weight of the composition comprising the monomer and / or prepolymer.

  The ionizing radiation is typically ultraviolet rays or electron beams, but other than these, electromagnetic waves such as visible rays, X rays and γ rays, or charged particle rays such as α rays can also be used.

  Additives are added as necessary. Examples of additives include heat stabilizers, radical scavengers, plasticizers, surfactants, antistatic agents, antioxidants, ultraviolet absorbers, infrared absorbers, dyes (colored dyes, colored pigments), extender pigments, Examples thereof include a light diffusing agent.

  In particular, the present invention is characterized in that the primer layer 2 can maintain two states of a fluid state and a cured state. Specifically, the primer layer 2 is provided on the transparent substrate 1 in a state where fluidity can be maintained after coating, and then the conductive composition layer 3 ′ (FIG. 10) is formed on the primer layer 2. When the film is transferred and formed, it must be capable of changing from a fluidized state to a cured state in a short time. By forming such a primer layer 2 on the transparent substrate 1, when the conductive composition layer 3 ′ is transferred onto the primer layer 2, between the conductive composition layer 3 ′ and the primer layer 2. Since transfer can be performed in the absence of voids, it is possible to eliminate the occurrence of a gap between the conductive composition layer 3 ′ and the primer layer 2 that may have occurred in the past, and transfer defects due to the presence of the gap, The problem of poor adhesion does not occur.

  As used herein, “fluidity” or “fluid state” refers to a property or state that flows (deforms) by pressure when the primer layer 2 is pressure-bonded to a printing plate filled with a conductive composition, Thus, it is not necessary to have a low viscosity. Further, it is not always necessary to have Newtonian viscosity, and it may have non-Newtonian viscosity such as thixotropic property or dilatancy property. When the primer layer 2 is a thermoplastic resin after being adjusted to a viscosity suitable for coating and applied on the transparent substrate 1, it may flow (deform) when it is pressure-bonded to the plate surface. It is sufficient that the temperature is such that it flows (deforms) at the time of pressure bonding. In this case, it may be paraphrased as a softened state.

  The viscosity of the primer layer 2 in a fluidized state is usually in the range of 1 mPa · s to 100,000 mPa · s, and preferably in the range of 50 mPa · s to 2000 mPa · s.

  Such a fluid state of the primer layer 2 can be obtained by simply applying an ionizing radiation curable ink on the transparent substrate 1 when an ionizing radiation curable resin is used as the resin composition for the primer layer. . The ionizing radiation curable ink is generally composed of monomers and oligomers having ionizing radiation curable properties as described above. If necessary, a photopolymerization initiator (in the case of ultraviolet curing or photocuring), various additives, and the like are added. It is fluid until it is cured with ionizing radiation. This ink may contain a solvent, but in this case, since a drying step is required after coating, the ink is preferably of a type that does not contain a solvent (so-called non-solvent type).

  Moreover, when a thermoplastic resin composition is used as the primer layer resin composition, the thermoplastic resin composition is applied onto the transparent substrate 1 and is in a fluid state (for example, 50 ° C. or more and 200 ° C. It can be generated by heating to the following extent). If the primer layer 2 in such a fluid state is pressure-bonded to a plate surface filled with a conductive composition, as will be described later, and then cured and transferred by cooling, the conductive composition layer 3 ′ and the primer layer are transferred. 2 can be transferred with no gap between them. Here, as a method of applying the thermoplastic resin composition on the transparent substrate 1, there are a method of applying a solution of the thermoplastic resin composition and then drying, and a method of applying a resin in a hot melt state. The thermoplastic resin composition applied on the transparent substrate 1 may be heated before contacting the plate surface filled with the conductive composition, and a heating roll or the like is used when pressure-bonding to the plate surface. However, in any case, when the conductive composition layer 3 ′ is transferred to the primer layer 2, it needs to be cooled to such an extent that the fluidity of the primer layer is lost.

The thickness of the primer layer 2 is not particularly limited, usually formed such that the degree 1μm or 100μm or less in thickness after curing (numbers were evaluated by the later thickness T _B). In addition, the thickness (T _B ) of the primer layer 2 is usually the sum of the conductive layer 3 and the primer layer 2 (total thickness. In FIG. 3, the top of the conductive layer 3 and the surface of the transparent substrate 1 1% or more and 50% or less). In addition, although it explains in full detail in the description column of a later manufacturing method, electroconductive composition layer 3 'was transcribe | transferred on the primer layer 2, and also the electroconductive composition layer 3' was hardened, and the electromagnetic wave shielding material was manufactured. primer layer 2 after, as shown in FIG. 3, the thickness T _a of the portion a conductive layer 3 is formed, the portion B of the conductive layer 3 is not formed thicker than the thickness T _B. In the primer layer 2, the side edges 5 and 5 of the thick part A are in a form in which the conductive layer 3 wraps around the thin part B.

  In the form shown in FIG. 3, the primer layer 2 in a fluidized state before being cured is pressure-bonded to the conductive composition provided in the intaglio, and then the primer layer 2 is cured, and the primer layer 2 and the conductive composition are cured. The primer layer 2 and the conductive composition are adhered to each other without a gap (when there is a dent 105 as shown in FIG. 15 or a dent 6 as shown in FIG. 13). ), The primer layer 2 is cured, or the primer layer 2 and the conductive composition are simultaneously cured and then transferred. Specifically, as shown in the manufacturing process diagram of FIG. 10 to be described later, the primer layer 2 formed on the transparent substrate 1 is made into a fluid state, and the conductive layer 15 is filled in the concave portion with the primer layer 2. This is caused by pressure bonding to the plate surface and curing the primer layer 2. Excess conductive composition other than the inside of the concave portion is scraped off by the doctor blade on the plate surface. At that time, the concave portion 6 is formed on the upper portion of the conductive composition in the concave portion as shown in the enlarged view of FIG. When the primer layer 2 is pressure-bonded to the plate surface in a state having the recess 6, the fluid primer layer 2 is in the recess 6 as shown in FIGS. 13 (A) and 13 (B). As a result, a form as shown in FIG. 3 is obtained.

(Conductive layer)
The conductive layer 3 is provided on the primer layer 2 in a pattern capable of performing electromagnetic shielding, for example, a mesh or stripe pattern. The conductive composition forming the conductive layer 3 is not particularly limited as long as it is mainly composed of conductive powder and a binder resin and finally becomes a conductive layer after various steps. . The formation pattern of the conductive layer may be a mesh shape or a stripe shape that is usually employed for an electromagnetic wave shielding material, and the line width and the pitch between the lines may be dimensions that are usually employed. For example, the line width can be 5 μm or more and 30 μm or less, and the line-to-line pitch can be 100 μm or more and 500 μm or less. The aperture ratio (ratio occupied by the total area of the openings in the total area of the electromagnetic shielding pattern) is usually about 50% to 95%. In addition to the mesh and stripe-shaped patterns, as shown in FIG. 1, there may be provided a ground pattern such as a frame-like all-solid (non-opening portion) layer adjacent to it while maintaining electrical continuity therewith. Further, although the thickness of the conductive layer 3 varies depending on the resistance value of the conductive layer 3, the central portion (the top of the projection pattern) is selected from the balance between the electromagnetic wave shielding performance and the suitability of adhesion of other members onto the conductive layer. ) Is usually 2 μm or more and 50 μm or less, preferably 5 μm or more and 20 μm or less. Note that the line width and thickness of the formation pattern of the conductive layer 3 are elements that closely affect the form of the protruding pattern 19, and will be described in detail later in the description section of the protruding pattern 19.

  The conductive composition is not particularly limited as long as it has fluidity at the time of filling in the recesses of the plate, and is formed into a desired pattern and exhibits desired conductivity after being cured. Various materials and forms can be used. A typical example is an ink or paste-like material having fluidity containing a conductive powder and a resin, and further containing a solvent for dissolving the resin as necessary. The conductive layer 3 made of the conductive composition is a coating film made of a solid after the conductive composition is dried, cured, or further baked.

  For example, as described later, the viscosity of the conductive composition is such that the primer component in the primer layer 2 penetrates into the conductive composition to increase the viscosity, or the primer layer 2 and the conductive composition are simultaneously cured. However, the range of usable viscosity is generally in the range of several hundred mPa · s to 1 million mPa · s. Preferably, it is in the range of several thousand mPa · s to tens of thousands mPa · s.

  As the binder resin constituting the conductive composition, any of thermosetting resins, ionizing radiation curable resins, and thermoplastic resins can be used. Examples of the thermosetting resin include resins such as melamine resin, polyester-melamine resin, epoxy-melamine resin, polyimide resin, thermosetting acrylic resin, thermosetting polyurethane resin, and ionizing radiation curable resin. Examples of the material for the primer layer include those described above, and examples of the thermoplastic resin include resins such as a polyester resin, a polyvinyl butyral resin, an acrylic resin, a phenol resin, and a thermoplastic polyurethane resin. In addition, when using a thermosetting resin, you may add a curing catalyst as needed. When using an ionizing radiation curable resin such as a photocurable resin, a polymerization initiator may be added as necessary.

  Further, in order to obtain fluidity suitable for filling the concave portion of the plate, these resins are usually used as a varnish dissolved in a solvent. There is no restriction | limiting in particular in the kind of solvent, The solvent generally used for printing ink can be used. The content of the solvent is usually about 10% by weight or more and 70% by weight or less, but is preferably as small as possible within a range where necessary fluidity can be obtained. In addition, when an ionizing radiation curable resin such as a photo-curable resin is used, a solvent is not necessarily required because it originally has fluidity.

  In addition, as the conductive powder constituting the conductive composition, low resistivity metal powder such as gold, silver, platinum, copper, tin, palladium, nickel, aluminum, etc., powder made of materials other than the low resistivity metal (above Powder made by plating low resistivity metal such as gold or silver on the surface of metal powder other than low resistivity metal, resin powder such as acrylic resin and melamine resin, inorganic powder such as silica, alumina, barium sulfate and zeolite) Preferable examples include conductive carbon powders such as graphite and carbon black. Also, conductive ceramics or conductive organic polymer powders can be used. The shape can also be selected from a spherical shape, a spheroid shape, a polyhedron shape, a scale shape, a disk shape, a fiber shape (or needle shape), and the like. These materials and shapes may be appropriately mixed and used. Since the size of the conductive powder is arbitrarily selected according to the type, it cannot be specified unconditionally. For example, in the case of flaky silver powder, the average particle size of the powder is about 0.1 μm to 10 μm. In the case of carbon black powder, those having an average particle size of about 0.01 μm to 1 μm can be used.

  The content of the conductive powder in the conductive composition is arbitrarily selected according to the conductivity of the conductive powder and the form of the powder. For example, among the 100 parts by weight of the solid content of the conductive composition, the conductive powder The powder can be contained in the range of 40 to 99 parts by weight. In the present application, the average particle size refers to a particle size distribution obtained by particle size distribution measurement or a value measured by TEM observation. In the case of an aspherical shape such as a polyhedron shape or a fiber shape, the particle size is usually defined by the diameter of the circumscribed sphere, the diagonal length, or the side length of the longest side.

Further, an appropriate additive may be added to the conductive composition for the purpose of improving the quality. For example, carbon black is not necessary because it is black in itself, but by adding a predetermined amount of black pigment or black dye as necessary, the contrast when an electromagnetic wave shield panel is constructed is improved and visibility is improved. Can be made. Further, in order to prevent reflection on the back surface of the transparent substrate due to the metallic luster of the metal plating layer, which will be described later, and to suppress color unevenness, metal color, etc., it is desirable to contain such a black pigment or black dye. Examples of black pigments include carbon black, Fe ₃ O ₄ , CuO—Cr ₂ O ₃ , CuO—Fe ₃ O ₄ —Mn ₂ O ₃ , and CoO—Fe ₂ O ₃ —Cr ₂ O ₃ that also function as conductive powder. The type and shape are not particularly limited, and a black pigment or black dye having a large coloring power with an average particle diameter of 0.1 μm or less that can be easily dispersed in the binder resin is preferable. In addition, when using carbon black, carbon black for coloring materials such as channel black, furnace black or lamp black, conductive carbon black, acetylene black and the like can be mentioned, and among them, the average particle diameter is 20 nm or less. Is preferably used. As the black dye, a dye such as aniline black can be used. Also, in order to improve the fluidity and stability of the conductive composition, as long as the conductivity and adhesion to the primer layer are not adversely affected, powders, thickeners, surfactants, antioxidants are appropriately used. Etc. may be added.

  As shown in the manufacturing process diagram of FIG. 10 to be described later, the conductive layer 3 is formed by first forming a conductive composition on a plate-like or cylindrical plate surface in which concave portions are formed in a predetermined mesh-like or stripe-like pattern. After coating, the conductive composition adhering to other than the inside of the recess is scraped to fill the recess with the conductive composition. Next, a transparent substrate 1 having a primer layer 2 that retains fluidity formed on one surface is prepared. Further, a plate surface having a concave portion having a predetermined pattern is formed, and the opening cross-sectional area of the concave portion cut by a virtual plane parallel to the surface of the plate surface is a reduction function S (x) of the distance x from the surface. Prepare a plate or cylindrical plate. Next, a conductive composition capable of forming a conductive layer after curing is applied to the plate surface, and then the conductive composition adhering to other than the inside of the concave portion is scraped to fill the concave portion with the conductive composition. Next, the conductive composition and the primer layer 2 are brought into intimate contact with each other by pressure bonding the primer layer 2 side of the transparent substrate 1 and the plate surface filled with the conductive composition in the recess, and the state After the flowability of the primer layer 2 was eliminated (cured), the transparent substrate 1 having the primer layer 2 was peeled off from the plate surface, and the conductive composition in the recesses was transferred onto the primer layer 2, A conductive composition layer 3 ′ having a mesh or stripe pattern is formed. After the conductive composition layer 3 ′ is transferred onto the primer layer 2, a curing process (for example, a drying process, an ultraviolet / electron beam irradiation process, a heating process, a cooling process, etc.) is performed to form the conductive layer 3 It is formed.

  In the present invention, as described above, when excess conductive composition other than the inside of the recess is scraped off by the doctor blade, the fluidity is maintained in the recess 6 formed above the conductive composition in the recess. Since the primer layer 2 is cured while the primer layer 2 is filled and the conductive composition and the primer layer 2 are in close contact with each other without any gap, the conductive composition can be transferred onto the primer layer 2 without transfer failure. .

  In the above, what was mainly comprised with electroconductive powder and resin was demonstrated as an electroconductive composition. Such a conductive composition itself becomes the conductive layer 3, but other conductive compositions may be applied in the present invention. For example, a sol (dispersion) of an organometallic compound is used as a conductive composition, for example, heated and solidified before and after the transfer step, and further baked as necessary to form a conductive layer 3 made of a conductive metal or metal compound. Also good. In this case, it is desirable to select a material (such as a glass plate) that can withstand the firing temperature as the transparent substrate. Further, for example, a known conductive resin such as polythiophene may be used as the conductive composition, and the conductive layer 3 itself may be used.

  FIG. 4 is an explanatory diagram of a cross-sectional area of the conductive layer cut along a virtual plane parallel to the transparent substrate. In the present invention, the conductive layer 3 after transfer has a cross-sectional area cut along a virtual plane P (yz plane) parallel to the surface of the transparent substrate 1 and a decreasing function S (x) of the distance x from the transparent substrate 1. It has become. As shown in FIG. 4B, the distance x from the transparent substrate 1 is not the surface of the primer layer 2 but the direction away from the transparent substrate 1 from the surface of the transparent substrate 1 excluding the primer layer 2. The distance measured toward the top (in FIG. 4 (B), which is also the height direction). The cross-sectional area is compared with the cross-sectional area in the range of the predetermined length y in the line direction (y-axis direction, longitudinal direction) of the conductive layer 3. Actually, for example, as shown in FIG. 4A, a measurement sample piece 30 cut out from the electromagnetic wave shielding material 10 in a range of a predetermined length y (for example, 50 μm) is embedded in a hardened resin for polishing, and FIG. As shown in FIG. 2), the resin is polished so as to be parallel to the transparent substrate 1 after curing, and the cross-sectional area at the virtual plane P is measured by a microscope and evaluated.

  FIG. 5 is a perspective view showing a space shape of the concave portion 64 of the plate surface 63 filled with the conductive composition. The cross-sectional shape of the conductive layer 3 described above is the same as the space shape of the concave portion 64 of the plate surface 63 filled with the conductive composition (however, reverse concavity and convexity). That is, the intaglio plate 62 filled with the conductive composition has a plate surface 63 having a concave portion 64 having a predetermined pattern, and the opening cross-sectional area of the concave portion 64 cut by a virtual plane P parallel to the surface of the plate surface 63 is It is a decreasing function S ′ (x) of the distance x ′ from the surface. As shown in FIG. 5, the distance x ′ from the surface means a distance measured from the surface of the plate surface 63 toward the inside of the plate (downward in FIG. 5). Therefore, the concave portion 64 of the plate surface 63 is filled with the conductive composition, and the conductive composition is transferred onto the primer layer 2 as the conductive layer 3 at a high transfer rate. It is transferred onto the primer layer 2 with the same cross-sectional shape (and reverse irregularities) as the opening cross-sectional shape.

  In the present invention, since the conductive layer 3 faithfully reproduces the shape of the concave portion 64 formed on the plate surface 63, the conductive layer 3 having various cross-sectional shapes can be obtained by changing the shape of the concave portion 64 to various shapes. Can be formed. For example, as the cross-sectional shape orthogonal to the line direction of the conductive layer 3, trapezoid (quadrangle), triangle, polygon (trapezoidal pentagon, hexagon, etc.), semi-elliptical, parabolic, sinusoidal, Any one selected from normal distribution curves and similar shapes can be mentioned. Each of these shapes has a decreasing function S (x) of a distance x from the transparent substrate 1 in a cross-sectional area cut by a virtual plane P parallel to the transparent substrate 1.

(Metal layer)
The metal layer 4 is formed as necessary to further improve the conductivity when the desired conductivity is insufficient with the conductive layer 3 alone. Usually, it is formed on the conductive layer 3 by plating. As plating methods, there are methods such as electrolytic plating, electroless plating, etc. Electrolytic plating can increase the plating rate several times by increasing the amount of electricity compared to electroless plating, and significantly improve productivity. It is preferable because it can be used.

  When the resistance of the conductive layer 3 is high and it is difficult to flow an electrolytic plating current, electroless plating may be performed first to improve conductivity to some extent, and then electrolytic plating may be performed. Moreover, you may complete by electroless plating. In the case of performing electroless plating, the conductive layer 3 does not necessarily have a conductivity that allows electroplating by itself, and a material that can be coated with metal by electroless plating (for example, metal particles, catalyst particles, etc.) ).

  In the case of electrolytic plating, power is supplied to the conductive layer 3 from an electrode such as a current carrying roll brought into contact with the surface on which the conductive layer 3 is formed, but the conductive layer 3 (a metal layer formed by electroless plating is further formed thereon) In this case, since the metal layer) has a conductivity (for example, 100Ω / □ or less) to the extent that electrolytic plating is possible, electrolytic plating can be performed without any problem. Examples of the material constituting the metal layer 4 include copper, silver, gold, chromium, nickel, and tin, which are highly conductive and can be easily plated. The metal layer 4 is generally one or more orders of magnitude smaller in volume resistivity than the conductive layer 3 made of conductive powder and resin as described above. This has the advantage of reducing the amount of conductive material required.

(Blackening treatment)
The blackening process is performed on at least the outermost surface of the protruding pattern side surface that receives extraneous light over a wide area. That is, when there is no metal layer, it is applied directly on the conductive layer 3 or, if necessary, on the metal layer 4 when the metal layer 4 is formed. This blackening treatment is basically a treatment for reducing the reflectance of visible light, and does not aim for complete blackness, but forms an independent layer (blackening layer) on the surface of the conductive layer 3. Including at least the outermost surface blackened (reduced reflectance) by roughening the surface of the conductive layer 3 or chemical changes (for example, copper to cuprous oxide, silver to silver oxide), etc. To do. Specifically, treatments such as blackened nickel plating and copper-cobalt alloy plating can be exemplified on the conductive layer 3. In addition, since the blackening process by metal plating can improve electrical conductivity together, it can serve as said metal layer. The color tone of the blackened surface may be a chromatic or achromatic color having a low brightness such as gray, brown, amber, rosy, dark green, or dark purple in addition to a complete black color.

(Form of protruding pattern)
One of the features of the present invention is that the protruding pattern 19 functions as a louver. The protruding pattern 19 includes at least the conductive layer 3, and the metal layer 4 may not be provided as illustrated in FIG. 3A, or the metal layer 4 may be included in the conductive layer 3 as illustrated in FIG. In any case, the electromagnetic wave shielding material 10 is configured as a protrusion-like pattern whose surface is blackened. In the present invention, since the protruding pattern 19 functions as a louver, the protruding pattern 19 is on the side where the external light is incident on the electromagnetic wave shielding material 10, more specifically, when the electromagnetic wave shielding material 10 is attached to a PDP panel or the like. It is provided so as to protrude to the viewer side (man side).

  FIG. 6 is a schematic view illustrating an aspect in which the protruding pattern blocks outside light. Since the protruding pattern 19 shown in FIG. 6A has a sufficient protruding height, it is incident obliquely from above and is originally on the screen of the opening. This is an example in which the external light 14 that should be reflected is sufficiently blocked to function as a louver, and the protruding pattern 19 ′ shown in FIG. This is an example that cannot be sufficiently blocked. FIG. 7 is a schematic diagram showing an example in which the external light 14 is blocked by the protruding pattern 19 and does not enter the entire surface of the opening. FIG. 8 is a schematic view of the external light 14 blocked by the protruding pattern 19 up to the center point Q of the opening. It is a schematic diagram which shows an example. In each of these drawings, the protruding pattern 19 is formed in a stripe shape or a mesh shape extending at least in the horizontal direction in a plan view, and the external light 14 is incident obliquely from above so as to be orthogonal to the protruding pattern 19. The symbol W in the figure is the line width of the protruding pattern 19, the symbol L is the pitch (line interval) of the protruding pattern 19, and the symbol H is the height of the protruding pattern 19. Further, the symbol θ represents a line S1 where a virtual line extending from an arbitrary point (for example, the center point Q) of the opening toward the top of the protruding pattern 19 is in contact with the protruding pattern 19, and a normal line S2 of the electromagnetic shielding material 10 Is the angle. In other words, the incident angle of the external light 14 with respect to the electromagnetic shielding material 10 is expressed as an angle with respect to the normal line. The external light that can be shielded by more than half of the area ratio has an incident angle of θ or more (90 degrees). It can be said that the following range.

  Here, the line width W is the value of the portion closest to the transparent substrate 1 in the width in the z direction of the protruding pattern 19 in which at least the outermost surface of the side surface is blackened. As described above, the width of the code A shown in FIG. However, if all of the side surfaces of the protruding portion 19 are not blackened, the blackening is not performed and the portion that does not shield the external light 14 is not included. The pitch (line interval) L is the pitch of the protrusion pattern 19 of the electromagnetic shielding material 10. Further, as shown in FIG. 3, the height H is expressed by the difference (distance in the x direction) between the apex of the protruding pattern forming portion and the flat surface of the primer layer 2 which is the protruding pattern non-forming portion. It is. The flat surface here is a surface based on the thinnest portion of the primer layer 2 shown in FIG. 3, and is usually a surface at the center point Q (see FIG. 8) of the opening. Become.

  In addition, when arrange | positioning the electromagnetic wave shielding material 10 in the front surface of a display apparatus, if the electromagnetic wave shielding material 10 is rotated in a surface, naturally the shielding property of the external light 14 by the protrusion pattern 10 will also change. Therefore, the mesh pattern of the present invention defines the shielding property at an angle at which the shielding property of the external light 14 is most improved (specifically, an angle including that in which the line of the protruding pattern 10 is horizontal).

The electromagnetic wave shielding material 10 of the present invention has a protruding pattern such that the angle θ represented by Equation 1 of θ = tan ⁻¹ (((L−W) / 2 + (W / 2)) / H) is less than 87 °. 19 is preferably formed. This equation 1 corresponds to FIG. 8, and the external light 14 can block 50% of the shielding area ratio to the center point Q of the opening, and the protrusion with the minimum value of the incident angle of the external light being 87 ° or less. This corresponds to the pattern 19. For example, in a general usage pattern in which the electromagnetic wave shielding material 10 is mounted on the front surface of the PDP panel, the protrusion pattern 19 having an angle θ of less than 87 ° is formed, thereby increasing the contrast of the PDP and improving the image visibility. be able to. In this case, it is preferable that the angle θ is smaller because the external light 14 incident at various angles can be shielded. A more preferable angle θ is less than 86.2 °, and even more preferably less than 84.3 °. Note that the angle θ can be adjusted by changing each of the L, W, and H parameters constituting the expression 1. Note that the lower limit of the angle θ can be set to about 68.2 ° from the relationship between the limit of the height H of the protruding pattern 19 and the decrease in image transparency when the pitch is made narrow, and is 73.3 °. A degree of about ° is more preferable.

  In the electromagnetic wave shielding material 10 of the present invention, since the conductive layer 3 is provided with improved transferability of the conductive composition, compared to a method using an intaglio such as normal gravure printing, the conductive layer 3 The thickness can be increased, and as a result, the conductive layer 3 can be increased and the conductivity required for the electromagnetic wave shielding material 10 can be ensured. This is because the conductive composition filled in the recesses on the surface of the intaglio can be transferred as the conductive layer 3 on the transparent substrate 1 with a shape reproducibility that is unthinkable in the past. If a blackening process or the like is performed on the layer 3, a mesh-shaped protruding pattern 19 having a desired shape can be stably formed. As a result, the height H of the protruding pattern 19 can be increased. The line width W of 19 can be reduced, and a function as a louver can be provided. For example, the height H of the protruding pattern 19 can be provided with good reproducibility in the range of 2 μm to 50 μm and the line width W in the range of 5 μm to 30 μm. In order to reduce the angle θ and increase the contrast, it is preferable to provide the height in a high range of 10 μm to 50 μm and the line width W in a range of 5 μm to 20 μm.

  For each parameter for specifying the angle θ in Equation 1, when the pitch L of the protruding pattern 19 is reduced to reduce the opening interval, the aperture ratio decreases, for example, the light transmittance from the PDP decreases. Therefore, it is desirable to increase the height H of the protruding pattern 19.

As shown in FIG. 7, it is desirable from the point of increasing contrast that the louver function of the protruding pattern 19 prevents the external light 14 from being incident on the entire surface of the opening at a smaller angle θ. In order to do so, it is necessary to make the height H of the protruding pattern 19 extremely high or to make the pitch L of the protruding pattern 19 extremely narrow. The height H of the protruding pattern 19 has a certain limit, and the pitch L needs to be a certain pitch or more from the viewpoint of transparency. In the present invention, the form of the electromagnetic wave shielding material 10 may be specified by using the angle represented by Equation 2 of θ = tan ⁻¹ (L− (W / 2) / H) as shown in FIG. Although there is no, the form of the electromagnetic wave shielding material 10 is specified by using the above-described formula 1 which is more industrial and realistic. When the angle θ is specified by the above equation 2, it is preferable to adjust each parameter so that the angle θ is less than 88.5 °, and the contrast can be further increased.

  In each parameter constituting the electromagnetic wave shielding material 10, from the viewpoint of transmittance, the ratio (W / L) of the line width W of the protruding pattern 19 to the pitch L of the protruding pattern 19 is less than 0.15. preferable. By setting W / L to less than 0.15, the line width W is relatively small with respect to the pitch L of the protruding pattern 19, so that the aperture ratio of the electromagnetic shielding material 10 can be maintained at a high value above a certain level. The contrast can be increased under the condition that the decrease in transmittance is prevented.

  From the viewpoint of transmittance, a more preferable range of W / L is less than 0.10. Moreover, the minimum of W / L is 0.01 from the reason of ensuring the electroconductivity required for an electromagnetic wave shield, and the intensity | strength of a protrusion pattern.

  Since the protruding pattern 19 has been subjected to the blackening treatment, the surface thereof has light absorption. Therefore, the protruding pattern 19 can effectively absorb the external light 14 and the like, and can enhance the contrast of the image when it is attached to the PDP.

(Form of conductive layer)
Here, the form of the conductive layer 3 formed in a predetermined pattern on the primer layer 2 will be described. Hereinafter, the form is referred to as “conductive layer pattern 16”. FIG. 9 is a schematic cross-sectional view showing two examples of the conductive layer pattern 16. The conductive layer pattern 16 includes a primer layer 2 and a conductive layer 3 formed in a predetermined pattern on the primer layer 2. The conductive layer pattern 16 has a thickness T _A of the primer layer 2 in portions where the conductive layer 3 is formed, larger than the thickness T _B of the primer layer 2 in portions where the conductive layer 3 is not formed Yes. Such a form has the effect derived from the form that the adhesiveness of the primer layer 2 and the conductive layer 3 is excellent compared with the case where the conductive layer 3 is formed on the primer layer 2 which consists of a flat surface. Further, such a form is caused by a manufacturing method described later, and as shown in FIG. 10, when the conductive composition 15 other than the concave portion 64 is scraped off by a doctor blade on the plate surface 63, A recess 6 is likely to be formed on the upper portion of the conductive composition 15 in the recess 64, and the primer layer 2 having fluidity is pressure-bonded to the plate surface 63 with the recess 6, so that the fluid primer layer 2 has the recess 6. This is caused by being filled in and peeled off after curing. Note that the shape of the conductive layer pattern 16 shown in FIG. 9 can be called a bell shape or a sinusoidal shape. This is because the shaping mold for forming the conductive layer pattern is a bell shape or a sinusoidal shape. It is not limited to these shapes.

  The conductive pattern 16 shown in FIG. 9A includes a first peak 17 made of the primer layer 2 and an upper end portion of the flange portion 13 of the first peak 17 or the vicinity thereof (in the first peak 17 as a whole, This is a projecting pattern composed of the second peak 18 made of the conductive layer 3 formed above the middle part. In other words, the conductive layer pattern 16 has a base portion (the ridge portion 13) constituted by the protruding portion of the primer layer 2, and the conductive layer 3 formed on the protruding portion has an upper end ( It is comprised in the aspect provided above the middle of the 1st mountain 17). Therefore, in this conductive layer pattern 16, since the conductive layer 3 is provided above the middle, the conductive layer 3 is not formed on the flange portion 13 below the middle. The conductive layer pattern 16 having such a configuration has good adhesion between the conductive layer pattern 16 formed on the mountain-shaped primer layer 2 which is not a flat surface, and in addition, the first peak 17 as described above. And the second peak 18, the adhesion between them is remarkably high.

  Further, in this embodiment, the first peak 17 may be configured to have a discontinuous portion with an inclined contour surface (an arrow portion in FIG. 9A) in the middle abdomen. Owing to the action of the portion, the conductive layer 3 can be further prevented from falling off. Such a discontinuous portion of the slope of the contour surface is generated when the primer layer 2 flows into the conductive composition layer 3 ′ in the process of the manufacturing method of the present invention (see FIG. 13 and the like). This is a portion where the inclination of the contour surface (outer surface) of the first peak 17 of the layer 2 changes discontinuously. Further, in this embodiment (the same applies to the embodiment of FIG. 9B), the side edge 5 of the conductive layer 3 is at an angle close to the inclination of the ridge portion 13 that rises obliquely. 5 is difficult to peel off from the primer layer 2.

  In the conductive layer pattern 16 shown in FIG. 9B, the interface between the primer layer 2 and the conductive layer 3 is an interface between the resin constituting the primer layer 2 and the resin or powder constituting the conductive layer 3. The interface is alternately formed on the primer layer 2 side and the conductive layer 3 side. In this embodiment, the interface 12 may be configured to be an interface between the resin constituting the primer layer 2 and the resin or powder (conductive powder or non-conductive powder) constituting the conductive layer 3. Further, for example, when the conductive composition does not contain powder and contains a conductive resin or a conductive compound, the primer layer 2 and the conductive layer 3 are caused by the pressure when the primer layer 2 is pressure-bonded in the recess. The interface may be complicated. In addition, in the conductive layer pattern 16 of this form, the complicated interface 12 has a mountain-shaped cross-sectional form with a high center as a whole.

  The conductive layer pattern 16 having such a form has good adhesion between the conductive layer 3 formed on the mountain-shaped primer layer 2 which is not a flat surface, and in addition, the interface 12 as described above is complicated. Due to the so-called anchoring effect, the adhesion between the primer layer 2 and the conductive layer 3 is remarkably increased.

  As a third form other than FIGS. 9A and 9B, for example, a form in which the primer component contained in the primer layer 2 is present in the conductive composition constituting the conductive layer 3 (not shown). Can be mentioned. If an example of this form is demonstrated using the cross-sectional form of FIG. 9 (A), it will be a form in which the primer component increases in the vicinity of the interface 12 in the conductive layer 3 and decreases toward the top. In short, the primer component is present in the conductive layer 3. The primer component may penetrate into the conductive layer 3 to the extent that it is detected from the top of the conductive layer 3 or may be detected to the vicinity of the interface 12.

  In the conductive layer pattern 16 having such a form, as in the case of the two forms described above, since the conductive layer 3 is formed on the mountain-shaped primer layer 2 which is not a flat surface, the adhesiveness between the two is good. Since the components have penetrated to such an extent that they exist in the conductive layer 3, the adhesion between them is remarkably increased.

  Furthermore, as a fourth form other than FIGS. 9A and 9B, for example, in the vicinity of the interface 12 between the primer layer 2 and the conductive layer 3, the primer component contained in the primer layer 2 and the conductive composition The form (not shown) with which the area | region with which the component which comprises layer 3 'mixes exists can be mentioned. If this form is explained using the cross-sectional form of FIG. 9 (A), the interface 12 clearly appears in FIG. 9 (A), but in the actual mixing region (not shown), such an interface 12 clearly appears. Does not appear, and an unclear and ambiguous interface appears. Further, such a mixed region exists so as to sandwich the interface 12 up and down. This is because the primer component (for example, a solvent) in the primer layer 2 and an arbitrary component (for example, a monomer component) in the conductive layer 3 are included. By interpenetrating into both layers. Note that the mixed region may exist above or below the interface 12. The case where the mixed region exists above the interface 12 is a case where the primer component in the primer layer 2 penetrates into the conductive layer 3, and any component in the conductive layer 3 does not penetrate into the primer layer 2. On the other hand, as a case where the mixed region exists below the interface 12, an arbitrary component in the conductive layer 3 enters the primer layer 2, and a primer component in the primer layer 2 does not enter the conductive layer 3. It is. Note that the thickness of the mixed region is not particularly limited.

  As in the case of the two forms described above, the conductive layer pattern 16 of such a form also has good adhesion between the two because the conductive layer 3 is formed on the mountain-shaped primer layer 2 that is not a flat surface. Since the mixed region 14 is present in the vicinity of 12, the adhesion between the primer layer 2 and the conductive layer 3 is remarkably increased.

  In the conductive layer pattern 16 having the third and fourth forms described above, when the primer component in the primer layer 2 penetrates into the conductive layer 3, the primer component is conductive even though it depends on the primer component. The curable composition can be gelled or semi-solidified, or the curable component can enter. As a result, in the transfer step after only the primer layer 2 is cured, the thickened or semi-cured conductive composition can be transferred (transferred) with a transfer rate of almost 100%. Further, in the transfer step after simultaneously curing the primer layer 2 and the conductive composition, the interlayer adhesion between both layers is increased, so that the conductive composition is transferred (transferred) at a transfer rate of almost 100%. Can

  In the conductive layer pattern according to the four forms described above, the interface 12 between the primer layer 2 on the transparent substrate 1 and the conductive layer 3 formed in a pattern is not a simple interface structure. Adhesion is improved and, at the time of manufacturing the electromagnetic wave shielding material 10, the transfer (transfer) of the conductive composition filled in the plate surface to the transparent substrate 1 is ensured under a high transfer rate. Done. The electromagnetic wave shielding material 10 of the present invention has at least one characteristic of the conductive layer pattern 16 in the four forms described above, but may have two or more of those characteristics, and has all four. You may do it. In addition, since the conductive layer pattern 16 according to these four forms can improve the transferability of the conductive composition (conductive layer 3), the conductive layer pattern 16 has a higher conductivity after transfer than a method using intaglio such as normal gravure printing. The thickness of the composition (conductive layer 3) can be increased. Therefore, the conductive layer pattern 16 can be thickened to ensure the conductivity necessary for the electromagnetic wave shielding material, and the height of the protruding pattern 19 can be increased to function as a louver.

  The configuration of the electromagnetic wave shielding material 10 of the present invention has been described above. However, the electromagnetic wave shielding material 10 of the present invention functions as a louver in which the protruding pattern 19 blocks the external light 14, so that the influence of the external light 14 is reduced and contrast is achieved. Can be increased. Further, since the primer layer 2 is provided so as to fill the recess 6 pointed out in the above problem, the electromagnetic wave shielding material 10 that does not cause problems such as disconnection, shape defect, and low adhesion due to transfer failure of the conductive layer 3 does not occur. Can be provided. Further, the adhesion between the primer layer 2 and the conductive layer 3 is improved, and at the time of manufacturing the electromagnetic wave shielding material 10, the conductive composition filled in the plate surface 63 is transferred to the transparent substrate 1 ( (Transfer) is reliably performed under a high transfer rate. This is because the conductive composition filled in the concave portions 64 on the surface of the intaglio can be transferred as the conductive layer 3 on the base material with high shape reproducibility, so that the blackening treatment or the like is performed on the conductive layer 3. , The mesh-shaped protruding pattern 19 having a desired shape can be stably formed, and as a result, the [sectional height H / line width W] ratio of the protruding pattern 10 can be increased. A function as a louver can be given.

  Furthermore, according to the electromagnetic wave shielding material 10 of the present invention, since the protruding pattern 19 having the shape represented by the above relational expression is provided, the contrast of the image in the presence of external light can be increased, and the transmittance can be reduced. Contrast can be increased in a protected state.

[Method of manufacturing electromagnetic shielding material]
FIG. 10 is a process diagram showing an example of a method for producing an electromagnetic wave shielding material of the present invention. Moreover, FIG. 11 is a schematic block diagram of the apparatus which implements the manufacturing method of this invention, and FIG. 12 is a schematic block diagram of the apparatus which implements the transfer process which transcribe | transfers an electroconductive composition on a primer layer. In the present application, “transfer” and “transfer” are used synonymously. Therefore, “transfer” can be replaced with “transfer”, and “transfer process” can be replaced with “transfer process”.

  The manufacturing method of the electromagnetic wave shielding material of the present invention is, as shown in FIGS. 10 to 12, the manufacturing method of the electromagnetic wave shielding material 10 (see FIG. 2) in which the protruding pattern 19 is formed on one surface of the transparent substrate 1. It is.

  The manufacturing method according to the first aspect includes a transparent base material preparation step (not shown) for preparing a transparent base material 1 on which one side of a primer layer 2 capable of maintaining fluidity until cured, and a predetermined pattern. A plate surface 63 having a concave portion 64 is formed, and the opening cross-sectional area of the concave portion 64 cut by a virtual plane P parallel to the surface of the plate surface 63 is a decreasing function S (x) of the distance x from the surface. An intaglio plate preparing step for preparing a plate-like or cylindrical intaglio plate 62 (see FIG. 5 and FIG. 10A), and the conductive composition 15 (which can form the conductive layer 3 after curing on the plate surface 63 ( After applying the fluid composition in an uncured state, the conductive composition adhering to other than the inside of the concave portion is scraped to fill the concave portion 64 with the conductive composition 15 (see FIG. Refer to 10 (b). 64 is formed in the upper part of the conductive composition 15 filled in 64.), the primer layer 2 side of the transparent substrate 1 after the transparent substrate preparation step, and the plate surface after the conductive composition filling step A pressure bonding step (see FIG. 10C) in which the primer layer 2 and the conductive composition 15 in the concave portion 64 are in close contact with each other with no gap, and the primer layer 2 is cured after the pressure bonding step. (Non-fluidized or solidified) The conductive composition 15 is not completely cured by a primer layer curing step (not shown), and the transparent substrate 1 and the cured primer layer 2 are peeled off from the plate surface 63 after the primer layer curing step. A transfer step (see FIG. 10 (d)) for transferring the conductive composition 15 in the recess to the primer layer 2, and a conductive composition layer formed in a predetermined pattern on the primer layer 2 after the transfer step. 3 'is cured and conductive layer A conductive composition cured to form a (not shown), and has at least.

In the manufacturing method according to the first aspect, the outermost surface of at least the side surface of the formed protruding pattern 19 is blackened, the line width of the protruding pattern 19 is W, and the pitch (line interval) of the protruding pattern 19 is set. L, when the height of the protruding pattern 19 is H, the angle θ represented by θ = tan ⁻¹ (((L−W) / 2 + (W / 2)) / H) is less than 87 °. The

  Moreover, the manufacturing method which concerns on a 2nd aspect is a transparent base material preparation process (not shown) which prepares the transparent base material 1 in which the primer layer 2 which can hold | maintain fluidity until it hardens | cures on one surface, predetermined | prescribed A plate surface 63 having a concave portion 64 made of a pattern is formed, and the opening cross-sectional area of the concave portion 64 cut by a virtual plane P parallel to the surface of the plate surface 63 is a decreasing function S (x) of the distance x from the surface. An intaglio plate preparation step (see FIGS. 5 and 10A) for preparing a plate-shaped or cylindrical intaglio plate 62, and a conductive composition 15 capable of forming a conductive layer 3 on the plate surface 63 after curing. The conductive composition filling step of scraping off the conductive composition adhering to the portion other than the inside of the concave portion and filling the concave portion 64 with the conductive composition 15 (which is fluid in an uncured state) ( FIG. 10 (b)) and transparent substrate preparation The primer layer 2 side of the transparent base material 1 and the concave portion 64 side of the plate surface 63 after the conductive composition filling step are pressure-bonded so that the primer layer 2 and the conductive composition 15 in the concave portion 64 are free from gaps. A pressure-bonding step (see FIG. 10C) that adheres (up to here, the same as in the first embodiment), and a simultaneous curing step (FIG. 10C) that simultaneously cures the primer layer 2 and the conductive composition 15 after the pressure-bonding step. )) And the primer layer 2 which has been cured as the conductive layer 3 by peeling off the transparent substrate 1 and the cured primer layer 2 from the plate surface 64 after the simultaneous curing step. And a transfer step (see FIG. 10D) for transferring.

In the manufacturing method according to the second aspect, as in the first aspect, at least the side surface of the formed protruding pattern 19 is blackened, the line width of the protruding pattern 19 is W, and the pitch (line The angle θ represented by θ = tan ⁻¹ (((L−W) / 2 + (W / 2)) / H) is less than 87 °, where L is the interval) and H is the height of the protruding pattern 19. Manufactured by.

  In the method for manufacturing an electromagnetic wave shielding material according to the first and second aspects, the conductive composition 15 may be a conductive composition that can form a conductive layer that can be electroplated after curing. In one mode, it has further a plating process (refer to Drawing 10 (e)) which carries out electroplating of metal layer 4 on conductive layer 3 formed in the predetermined pattern on primer layer 2 after a conductive composition hardening process. You may comprise as follows. Moreover, in the said 2nd aspect, it comprises so that it may further have the plating process of carrying out the electrolytic plating of the metal layer 4 on the hardened conductive layer 3 formed in the predetermined pattern on the primer layer 2 after a transfer process. Also good.

  Hereinafter, each step will be described with reference to the drawings.

(Transparent substrate preparation process)
The transparent base material preparation step is a step of preparing a transparent base material 1 in which a primer layer 2 that can maintain fluidity until cured is formed on one surface. The primer layer 2 is formed by applying a primer layer resin composition on the transparent substrate 1, and since the primer layer resin composition is as described above, the description thereof is omitted here. The transparent substrate 1 having the primer layer 2 may be a purchased product or may be formed by a coating method (coating apparatus) as shown in FIG. 11, but in either case, It is necessary for the primer layer 2 to be in a state in which fluidity is maintained during the crimping process described later.

  For example, when an ionizing radiation curable resin composition is used as the primer layer resin composition, only the solvent in the ionizing radiation curable resin composition is removed by drying in an unirradiated state where no ionizing radiation is irradiated. It is preferable to form a primer layer 2 made of a fluidized state on the transparent substrate 1 as a coating film, and to supply to the pressure-bonding step described later in that state. Of course, when the ionizing radiation curable resin composition used here is a so-called non-solvent type that does not contain a solvent, a drying step when forming the primer layer 2 is not necessary.

  Further, when a thermoplastic resin composition is used as the primer layer resin composition, the primer layer 2 may be heated immediately before the pressure bonding step as long as it is in a fluidized state by heating in the pressure bonding step described later. Alternatively, the heating of the primer layer 2 and the pressure bonding to the plate surface 63 may be performed simultaneously with a hot roll or the like.

  In addition, about the method of apply | coating a primer layer, various coating systems can be used, For example, it can select suitably from various systems, such as a gravure coat, a comma coat, a die coat, and a roll coat.

  The coating method shown in FIG. 11 is an example of a gravure reverse coat, and a film-like transparent substrate 1 wound in a roll shape is introduced between a gravure roll 51 and a backup roll 52 (also referred to as a thick cylinder). This is a method of applying an ionizing radiation curable resin composition for a primer layer. In this case, the gravure roll 51 comes into contact with the ionizing radiation curable resin composition filled container 53 at the lower side, and the ionizing radiation curable resin composition is pulled up and applied to one surface of the transparent substrate 1. At this time, excess ionizing radiation curable resin composition is scraped off by the doctor blade 54. After the ionizing radiation curable resin composition is applied on the transparent substrate 1, the solvent contained in the resin composition is subjected to a drying treatment through a drying zone as necessary. This drying process is, for example, a process in which only the solvent in the ionizing radiation curable resin composition adjusted to a viscosity suitable for the coating apparatus is dried and removed to form a primer layer 2 in a fluid state for use in the subsequent pressure bonding process. is there. When a non-solvent type ionizing radiation curable resin composition having a viscosity suitable for a coating apparatus is used, a drying apparatus is unnecessary. The transparent substrate 1 having the primer layer 2 that retains fluidity is then supplied to the crimping process. In addition, when performing the process for improving the adhesiveness of the transparent base material 1 and the primer layer 2 continuously, it performs with respect to the transparent base material 1 before application | coating of the primer layer 2. FIG.

(Intaglio preparation process)
In the intaglio plate preparation step, as shown in FIGS. 5 and 10A, a plate surface 63 having a concave portion 64 having a predetermined pattern is formed, and the plate surface 63 is cut along a virtual plane P parallel to the surface of the plate surface 63. This is a step of preparing the intaglio 62 in which the opening cross-sectional area of the recess 64 is a decreasing function S (x) of the distance x from the surface. The intaglio 62 may be plate-shaped or cylindrical, and when the plate-shaped intaglio 62 is used, the electromagnetic wave shielding material 10 can be manufactured as a single sheet, and when the cylindrical intaglio 62 is used. The electromagnetic shielding material 10 can be continuously produced by roll-to-roll. The "roll toe roll" is a processing method in which a strip-shaped base material is supplied in a form wound on a roll, unrolled into a strip and continuously processed, and then wound into a roll. I mean.

  Although the intaglio plate 62 has already been described with reference to FIG. 5, the transfer rate of the conductive composition is extremely high (95% to 100%) in the manufacturing method of the present invention. The cross-sectional shape is the same or substantially the same. Therefore, if the concave shape of the intaglio 62 is the same as the shape shown in FIG. 6, the conductive layer 3 having the cross-sectional shape shown in FIG. 6 can be easily obtained with good reproducibility.

  The intaglio 62 is a plate material made of plate or cylindrical metal or ceramics, photo-etched, cut with a processing jig such as a cutting tool, directly drawn and cut using a laser beam, or electric The concave portion 64 having a predetermined shape can be formed by casting or the like. In particular, cutting with a processing jig such as a cutting tool is advantageous in that a concave portion having a predetermined shape can be precisely processed and a concave portion having a high aspect ratio can be obtained.

(Resin filling process)
In the resin filling process, as shown in FIGS. 10A and 10B, the conductive layer 3 is cured after being cured on a plate-like or cylindrical plate surface 63 in which concave portions 64 are formed in a predetermined pattern of mesh or stripe. This is a step of applying the conductive composition 15 in a fluid state that can be formed, and then scraping the conductive composition adhering to other than the inside of the concave portion with a doctor blade or the like to fill the concave portion with the conductive composition 15. In this step, although not originally desired, the dent 6 is inevitably formed on the conductive composition 15 filled in the recess 64. Although the detailed cause is unclear, when the conductive composition other than the concave portion is scraped off with a doctor blade or the like, a dent 6 is generated on the surface due to the rheological behavior of the conductive composition. In the case where the solvent contains a diluting solvent, it is presumed that it is due to volume shrinkage due to volatilization of the diluting solvent or a combined action of both. Since the conductive composition 15 is as described above, the description thereof is omitted here.

  The combination of the conductive composition with respect to the primer layer resin composition is not particularly limited, and the curing treatment of the primer layer resin composition and the curing treatment of the conductive composition may be different. When an ionizing radiation curable resin containing a conductive powder is employed, the primer layer resin composition is also preferably an ionizing radiation curable resin composition. By such a combination, the primer layer 2 is cured and electrically conductive as in the manufacturing method of the second aspect by the ionizing radiation irradiation treatment at the time of the pressure bonding step after the resin filling step and the subsequent curing step of the primer layer. Curing of the composition layer 3 can be performed simultaneously. At this time, since the conductive powder is generally colored, when the ionizing radiation to be irradiated is light or ultraviolet light, it can be cured by selecting an appropriate combination of a photopolymerization initiator and a photocurable resin. it can. Moreover, when irradiating an electron beam, it is not necessary to consider the color of the conductive powder.

  The coating method shown in FIGS. 11 and 12 is an example of a process performed before the transparent base material 1 having the primer layer 2 is pressure-bonded to the intaglio roll 62. Specifically, the pickup roll 61 has a conductive property. The composition filling container 68 is brought into contact with the lower side, and the conductive composition 15 is pulled up and applied to the plate surface 63 of the intaglio roll 62. At this time, the conductive composition 15 is scraped off by the doctor blade 65 so that the conductive composition 15 does not get on the portion other than the concave portion 64 on the plate surface 63.

(Crimping process)
As shown in FIGS. 10 (c) and 12, the crimping step crimps the concave portion 64 side of the plate surface 63 after the resin filling step and the primer layer 2 side of the transparent substrate 1 after the transparent substrate preparation step. In this step, the conductive composition 15 in the recess 64 and the primer layer 2 are closely adhered without a gap. Since the primer layer 2 has fluidity at this point, the primer layer 2 also flows into the recess 6 above the conductive composition 15 filled in the recess 64 of the plate surface, and the recess is also filled. The space between the transparent substrate 1 and the conductive composition 15 is all filled with a primer layer without a gap. The pressure bonding is performed by the nip roll 66 and urged against the intaglio roll 62 with a predetermined pressure. The nip roll 66 is provided with a biasing pressure adjusting means, and the biasing pressure is arbitrarily adjusted according to the fluidity of the primer layer 2.

  When the primer layer 2 is a thermoplastic resin, the nip roll 66 is preferably a heatable roll. In this case, the primer layer 2 is softened and flowable by thermocompression bonding.

  In this crimping step, the primer layer 2 flows into the recess 6 above the conductive composition 15 filled in the recess 64 of the plate surface, the recess 6 is filled, and then the electromagnetic wave passes through a curing step and a transfer step. A shield material is manufactured. In this crimping step, first, the primer component contained in the primer layer 2 enters the conductive composition constituting the conductive layer 3 and then fills the plate surface through a curing step and a transfer step described later. The transfer (transfer) of the conductive composition 15 to the transparent substrate 1 is reliably performed under a high transfer rate. And as for the conductive layer pattern 16 which the obtained electromagnetic shielding material has, as demonstrated with reference to FIG. 9 (A), the interface 12 of the primer layer 2 and the conductive layer 3 does not become a simple interface structure, The adhesion between both layers is improved.

  Second, for example, when conductive powder is contained in the conductive composition, the interface between the primer layer 2 and the conductive composition is pressure-bonded in a complicated manner. By passing through the curing step and the transfer step, the transfer (transfer) of the conductive composition 15 filled in the plate surface to the transparent substrate 1 is reliably performed under a high transfer rate. Then, as described with reference to FIG. 9B, the conductive layer pattern 16 included in the obtained electromagnetic wave shielding material has a form in which the interface 12 between the primer layer 2 and the conductive layer 3 is intricate. Adhesion is improved.

  Third, the primer layer 2 flows into the recess 6 above the conductive composition 15 filled in the recess 64 of the plate surface, and the recess 6 is filled, and then undergoes a curing process and a transfer process. Therefore, as described with reference to FIG. 9A, the obtained conductive layer pattern 16D was formed above the middle of the first peak 17 and the first peak 17 composed of the primer layer 2. A projecting pattern composed of the second peak 18 made of the conductive composition (conductive layer 3) is formed.

(Curing process)
The curing step is a step of curing the primer layer 2 after the pressure-bonding step by the urging force of the nip roll 66, and in a state where the primer layer 2 and the conductive composition 15 are in close contact with each other by performing a curing process after the pressure-bonding. It can be cured. Specifically, when the resin composition for the primer layer is an ionizing radiation curable resin composition, it is irradiated with ionizing radiation in an irradiation zone (in the example of FIG. 12, it is described as a UV zone) and cured. It is processed. In this case, the primer layer 2 is sandwiched between the transparent substrate 1 and the plate surface 63 and is not necessarily inhibited by the oxygen in the air, so that a nitrogen purge device or the like is not necessarily required. The curing treatment is selected in accordance with the types of the primer layer resin composition and the conductive composition, as described above, and is subjected to curing treatment such as ionizing radiation irradiation treatment and cooling treatment.

  In addition, as described above, when both the resin composition for the primer layer and the conductive composition are ionizing radiation curable resins, a simultaneous curing step in which ionizing radiation irradiation treatment is performed during the curing step following the pressure bonding step; You can also

(Transfer process)
In the transfer step, as shown in FIG. 10D, the transparent substrate 1 and the cured primer layer 2 are peeled off from the plate surface 63 of the intaglio roll 62 after the curing step, and the conductive composition 15 in the recess 64 is removed from the primer layer 2. It is a process of transferring to the top. Since the primer layer 2 is cured in the primer layer curing step before this step, the conductive composition 15 adhered to the primer layer 2 is removed from the plate surface 63 of the intaglio roll 62 together with the transparent substrate 1 in the recess. The conductive composition layer 3 ′ is transferred cleanly on the primer layer 2 away from the substrate. As shown in FIGS. 11 and 12, the peeling is performed by a nip roll 67 provided on the outlet side.

  In the transfer process, the conductive composition 15 does not necessarily need to be cured, and can be transferred even when the conductive composition 15 contains a solvent. The reason for this is unknown at present, but the primer layer 2 and the conductive composition 15 are not only in close contact with each other without a gap, but part of the primer layer also penetrates into the conductive composition layer. Are mixed with each other, so that the adhesive force between the primer layer 2 and the conductive composition 15 cured in an intertwined state is electrically connected to the inner wall of the concave portion 64 of the roll-shaped intaglio plate. This is presumably because it is larger than the adhesion strength with the composition 15. In addition to this, particularly when the conductive composition 15 is in an uncured state, a part of the primer layer penetrates into the conductive composition layer to change its fluidity and easily escape from the recess 64. It is also speculated to do.

FIG. 13 is a schematic view showing a form in which the primer layer 2 is filled in the recess 6 of the conductive composition 15 in the recess 64 and the conductive composition 15 is transferred. As shown in FIG. 13C, when the form of the primer layer 2 and the form of the conductive composition layer 3 ′ after the transfer process are observed, the part of the primer layer 2 where the conductive composition layer 3 ′ is transferred. the thickness T _a of a, the conductive composition layer 3 'is greater than the thickness T _B of the portion B which are not transferred. Then, in the side edges 5 and 5 of the thick part A, the conductive composition layer 3 ′ wraps around the thin part B. In such a form, the primer layer 2 side of the transparent substrate 1 on which the primer layer 2 retaining fluidity is formed and the concave portion 64 side of the plate surface 63 after the resin filling step are shown in FIGS. By pressure bonding in this manner, the fluid primer layer 2 flows into and fills the recesses 6 that are likely to be formed above the conductive composition in the recesses 64. Therefore, the form after transfer is as shown in FIG. , the conductive composition layer 3 of the primer layer 2 provided on the transparent substrate 1 'thickness T _a of the portion a is formed conductive composition layer 3' is not formed portion B becomes larger than the thickness T _B of the further side edges 5,5 of the thick portion a in thickness becomes thin portion side conductive composition layer 3 'is wrapping around form of B thicknesses.

Usually, the thickness T _A of the primer layer 2 in the portion A of the conductive composition layer 3 'is formed, as shown in FIG. 3, the thickness becomes thicker enough to go to the center portion of the part. That is, in the cross section of the electromagnetic shielding pattern portion (see, for example, FIG. 3), the cross-sectional shape of the primer layer 2 is a so-called semicircle, semi-ellipse, or the like that is convex toward the direction away from the transparent substrate 1. A bell-shaped shape, a triangular shape, a trapezoidal shape, a pentagonal shape such as a pentagonal shape, or the like is formed.

  Further, the interface 12 between the primer layer 2 and the conductive composition layer 3 ′ to the conductive layer 3 has a form in which the primer layer 2 is merely physically or chemically bonded as described with reference to FIG. 9. In the vicinity of the interface 12, the material of both layers may be dissolved, permeated or diffused with each other. Since this dissolution, permeation, or diffusion is performed before the conductive composition or primer layer 2 is cured, when the conductive composition or primer layer 2 is cured after such a state, the interlayer adhesion is high. It becomes an interface. These forms can be realized by selecting materials for both layers and selecting manufacturing conditions.

  In the electromagnetic wave shielding material produced by the production method of the present invention, the conductive layer pattern 16 having the above-mentioned interface form is formed, so that the interlayer adhesion between the primer layer 2 and the conductive composition layer 3 ′ to the conductive layer 3. The conductive composition filled in the plate recess can be transferred (transferred) with a transfer rate of almost 100%. Further, even when a plate depression having a large aspect ratio (depth / opening width) of 2/10 or more is used, the conductive composition filled in the depression is transferred (transferred) at a transfer rate of almost 100%. Can do. As a result, there is an effect that disconnection, shape failure, adhesion, and the like due to transfer failure of the conductive composition forming the conductive layer 3 do not occur.

  In addition, after a transfer process, a drying process, a hardening process, etc. are performed as needed. Further, if it is necessary to further reduce the resistance, it is subjected to a subsequent plating step. The plating process may be provided in-line as it is, or may be supplied to a separate plating line after being wound up once.

(Plating process)
As shown in FIGS. 10 (e) and 11, the plating process is performed after the transfer process, on the conductive layer 3 formed in a predetermined pattern on the primer layer 2 (the same as the formation pattern of the primer layer 2). This is a step of electroplating the layer 4. Examples of the metal to be plated include copper, silver, gold, nickel, platinum, tin and the like, and copper plating which is low in price and high in conductivity is particularly preferable. As the copper plating solution, commercially available plating solutions such as a copper sulfate bath, a copper bromide bath, a copper pyrophosphate bath, and a copper borofluoride bath can be used. Among them, a copper plating solution with improved uniform plating properties is preferably employed. The In addition, when it uses for a plating process, normal pre-processing (for example, a degreasing process, a washing process, etc.) is given, but it may be supplied in-line from the transfer process as described above, or separately. It may be used for the plating line. The plating conditions such as current density and bath temperature, and the addition of various additives are appropriately set in consideration of the thickness of the desired metal layer, the deposition state of the plating, and the like from a known and conventional range. After the plating step, it is wound as it is after passing through other steps (for example, a blackening treatment step and a rust prevention step of the metal layer 4 and a formation step of the protective layer 9 as shown in FIG. 2) as necessary. Alternatively, it may be cut into a predetermined size to form a sheet.

  In this way, the roll-shaped or sheet-shaped electromagnetic shielding material 10 is manufactured. According to the electromagnetic shielding material manufacturing method of the present invention, first, as a first effect, the primer layer 2 and the conductive layer 3 are provided with a gap between them. Therefore, it is possible to manufacture an electromagnetic wave shielding material that does not cause defects such as disconnection, shape failure, and low adhesion due to transfer failure of the conductive layer 3. Further, since the transfer can be performed at a high transfer rate, the thickness of the conductive layer 3 can be increased, and the electromagnetic wave shielding property can be improved.

  For example, if a plate having a recess having a depth of 20 μm is used, a conductive layer pattern having a thickness of about 20 μm which is almost the same as the shape of the plate can be formed. This is unthinkable when printing intaglio (gravure) a conductive composition containing a large amount of conductive powder. Further, in the method for producing an electromagnetic wave shielding material of the present invention, the conductive composition contains a solvent and is not a binding material that solidifies in a short time, but can be transferred with a high transfer rate even when separate drying is required. it can. Further, when the conductive composition is UV curable, the conductive composition contains a pigment, the pigment is a high-concentration metal-based conductive powder, and the conductive powder shields ultraviolet rays, Even when ultraviolet rays do not reach the intaglio plate holes, they can be transferred with a high transfer rate.

  Furthermore, as a second effect, it is possible to transfer the conductive composition filled in the recesses on the surface of the intaglio plate as a conductive layer on the base material with high shape reproducibility and transfer rate. As a result, a mesh-shaped protruding pattern having a desired shape can be stably formed. As a result, the [section height / line width] ratio of the protruding pattern can be increased, and in the presence of external light. It is possible to provide a function as a louver for increasing the image contrast.

  In addition, in the above, the structure which laminates | stacks the metal layer by electroplating on a conductive composition was demonstrated as a structure of the protrusion pattern of the conductive layer of this invention, and its manufacturing method. However, in the present invention, the protruding pattern of the conductive layer can be configured in other forms. That is, instead of the conductive composition described above, the protruding pattern is formed with a catalyst composition containing a catalyst substance capable of depositing a metal layer by electroless plating, and the metal layer is deposited on the surface by electroless plating. And it can also be laminated. Such a catalyst composition only needs to be capable of electroless plating in a later step, and conductivity is not essential. Specifically, the catalyst material is preferably fine particles or powders of metals such as palladium, tin, gold, silver, and copper. These metal fine particles or powders may be colloidal particles having a particle size of about 1 nm to 100 nm (0.1 μm), or those having a particle size of about 0.1 μm (100 nm) to about 10 μm. Of course, if the same metal and particle size as the conductive powder is used, it is possible to use a catalyst composition containing the same as the conductive composition because of its high conductivity (low resistivity). .

[Filter for display]
FIG. 14 is a schematic cross-sectional view showing an example of the display filter of the present invention. As shown in FIG. 14, the display filter 71 of the present invention has at least the electromagnetic shielding material 10 of the present invention described above, and is provided on the front side (viewer side) of the plasma display device 70. That is, the electromagnetic wave shielding material 10 is provided as a part or all of the display filter 71, and may be used alone as the display filter 71. As shown in FIG. You may combine and use a member.

  As the functional member, conventionally known ones can be applied, for example, neon light absorbing material, ultraviolet absorbing material, near infrared absorbing material, antireflection material, antiglare material, hard coat material, antifouling material, toning material, impact resistance. Materials, antistatic materials, and the like. These functional members are one or more materials selected from, for example, a neon light absorbing material, an ultraviolet absorbing material, an antireflection material, a hard coat material, an antifouling material, and an antiglare material on the electromagnetic shielding material 10. May be formed as a coating composition in a layered form, or may be constituted by containing these materials in a transparent substrate.

  An example shown in FIG. 14 is a transparent base material formed by coating, for example, an AR layer (antireflection layer) 74 on the surface of the electromagnetic wave shielding material 10 on the conductive layer 3 side via an adhesive layer 72 or an adhesive layer. The filter 71 for a display which bonded 73 as a to-be-adhered body is illustrated. The display filter 71 is bonded to the front side (viewer side) of the plasma display panel 76 via an adhesive layer 75 or an adhesive layer. The display filter of the present invention is not limited to the configuration shown in FIG. 14, and may be in various other forms as long as it has part or all of the electromagnetic shielding material 10. By attaching such a display filter 71 to the plasma display panel, a plasma display device can be obtained.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.

Example 1
An electromagnetic wave shielding material was manufactured by the apparatus shown in FIGS. First, as the transparent substrate 1, a long roll wound biaxially stretched polyethylene terephthalate (PET) film having a width of 1000 mm and a thickness of 100 μm subjected to easy adhesion treatment on one side was used. The PET film set in the supply part was drawn out, and a photocurable resin composition for the primer layer was applied and formed on the easy adhesion treatment surface so as to have a thickness of 5 μm. The application method employs a normal gravure reverse coating method, and the photocurable resin composition is a non-hydrophilic monofunctional composition consisting of 35 parts by weight of an epoxy acrylate prepolymer, 12 parts by weight of a urethane acrylate prepolymer, and phenoxyethyl acrylate. 44 parts by weight of acrylate monomer, 9 parts by weight of trifunctional acrylate monomer composed of ethylene oxide-modified isocyanuric acid triacrylate, and 3 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemicals; 1-hydroxy-cyclohexyl-phenyl-ketone) as a photoinitiator The added one was used. The viscosity at this time was about 1300 mPa · s (25 ° C., B-type viscometer), and the primer layer 2 after application showed fluidity when touched, but did not flow down from the PET film.

  Next, a roll-shaped intaglio 62 was prepared. The prepared intaglio plate 62 has concave portions 64 on the plate surface 63 that form a grid-like mesh pattern with a line width of 20 μm, a line pitch of 300 μm, and a plate depth of 10 μm. The concave portion 64 of the intaglio plate 62 was processed by using a lathe and cutting a cutting tool as a cutting tool on a copper layer on the surface of a plate material formed by laminating a copper plating layer on the surface of an iron hollow roll (cylindrical). . The processing is performed so that the opening cross-sectional area of the concave portion 64 obtained by cutting the spatial shape in the concave portion 64 with a virtual plane P parallel to the surface of the plate surface 63 becomes a decreasing function S (x) of the distance x from the surface. It was. Specifically, the shape of the conductive layer 3 after the transfer was changed to the bell shape shown in FIG. Further, electrolytic chromium plating was applied to the entire surface of the intaglio plate 62 after processing so that the shape of the recess portion 64 did not change when the doctor blade 102 was used to scrape off the ink on the excess portion of the plate surface.

  Next, the PET film on which the uncured primer layer 2 is formed is provided to an intaglio roll 62 that performs a transfer process. Prior to that, the conductive composition 15 is applied to the plate surface 63 of the prepared intaglio roll 62. The conductive composition other than the inside of the concave portion 64 was scraped off by the doctor blade 65, and the conductive composition 15 was filled only in the concave portion 64. A PET film on which the primer layer 2 is formed is supplied between the intaglio roll 62 filled with the conductive composition 15 in the recess 64 and the nip roll 66, and the pressing force of the nip roll 66 against the intaglio roll 62 ( The priming force) causes the primer layer 2 to flow into the recess 6 of the conductive composition 15 existing in the recess 64 to bring the conductive composition 15 and the primer layer 2 into close contact with each other, and a part of the primer is The conductive composition 15 in the recess 64 was infiltrated. In addition, the used conductive composition used the silver paste of the following compositions.

<Preparation of conductive composition (silver paste)>
After blending 93 parts by weight of scaly silver powder having an average particle size of about 2 μm as the conductive powder, 7 parts by weight of thermoplastic polyester urethane resin as the binder resin, and 25 parts by weight of butyl carbitol acetate as the solvent, and thoroughly stirring and mixing A conductive composition was prepared by kneading with three rolls.

  Next, the transfer process performed is as follows. First, the PET film on which the primer layer 2 is formed is sandwiched between the intaglio roll 62 and the nip roll 66 with the primer layer 2 facing the plate surface 63 side of the intaglio roll 62. The primer layer 2 of the PET film is pressed against the plate surface 63 between the intaglio roll 62 and the nip roll 66. Since the primer layer 2 has fluidity, the primer layer 2 pressed against the plate surface 63 flows into the recess 64 filled with the conductive composition 15, and the conductive composition generated in the recess 64. 15 dents 6 are filled (see FIG. 13). Thus, the primer layer 2 is in close contact with the conductive composition 15 without a gap. Thereafter, the intaglio roll 62 is further rotated and irradiated with ultraviolet rays by a UV lamp made of high-pressure mercury lamp, and the primer layer 2 made of the photocurable resin composition is cured. Due to the curing of the primer layer 2, the conductive composition in the recess 64 of the intaglio roll 62 comes into close contact with the primer layer 2, and then the film is peeled from the intaglio roll 62 by the nip roll 67 on the outlet side. The conductive composition layer 3 ′ (see FIG. 10) is transferred and formed. The transfer film thus obtained was passed through a drying zone at 110 ° C. to evaporate the solvent of the silver paste and solidified to form a conductive layer 3 having a mesh pattern on the primer layer 2. At this time, the thickness of the pattern portion where the conductive layer 3 is present (thickness difference between the mesh pattern portion where the conductive layer 3 is formed and the other portion) is 9 μm, which is almost equal to the depth of the plate. The silver paste in the concave portion 64 of the plate was transferred with a high transfer rate (90%). When the inside of the concave portion 64 after the transfer was observed, no plate residue of the paste was observed, and no disconnection or shape defect of the mesh pattern was observed.

Subsequently, copper plating was performed with respect to the obtained transfer film. As a copper plating method, the obtained transfer film is immersed in a copper sulfate plating solution, and a current of ² A / dm ² is applied with a mesh-like conductive layer pattern formed on the surface as a cathode and a copper plate as an anode. Electrolytic copper plating was performed. The copper plating film was selectively formed on the conductive layer 3 with a thickness of 2 μm. Next, blackening treatment was performed. The blackening treatment was performed by electroless nickel plating to reduce the reflectance of the protruding pattern 19. Thus, the electromagnetic shielding material of Example 1 according to the present invention was produced. The final projecting pattern 19 had a height H of 11 μm, a line width of 20 μm, and a pitch of 300 μm.

(Examples 2 to 7)
In Example 1, the shaping plate surface 63 of the intaglio roll 62 is prepared so that the line width W, pitch L, and height H of the protruding pattern 19 have the dimensions shown in Table 1. 2 to 7 electromagnetic wave shielding materials 10 were produced.

(Comparative Example 1)
In Example 1, the conductive composition was transferred in the same manner as in Example 1 except that the primer layer was not applied to the easy-adhesion treated surface of the PET film. However, at that time, the transfer of the conductive composition onto the PET film was not sufficient, and disconnection and pattern loss occurred frequently. Further, the pattern thickness after drying was about 1 μm, and the transfer rate was extremely poor. Subsequent electrolytic copper plating could not be evenly plated, and the final protrusion pattern 19 had a height of about 2 μm.

(Comparative Examples 2 to 4)
In Example 1, the shaping plate surface 63 of the intaglio roll 62 is prepared so that the line width W, pitch L, and height H of the protruding pattern 19 are the dimensions shown in Table 1, and the comparative example is the same as in Example 1. 2 to 4 electromagnetic wave shielding materials 10 were produced.

(Contrast evaluation)
The produced electromagnetic shielding material 10 was installed in front of a 50-inch plasma display panel. As for bright room contrast, two 32W fluorescent lamps are lit at a position 1.5m above the display in a dark room where outside light is blocked, and a black and white stripe pattern is displayed at a position 5m from the screen. The contrast between the pattern and the white pattern was visually evaluated. The results are shown in Table 1. On the other hand, with regard to dark room contrast, white brightness was evaluated under the same conditions as the bright room contrast evaluation except that the fluorescent lamp was turned off. The results are shown in Table 1.

  Table 1 shows the parameters of the electromagnetic shielding material together with the contrast results. The evaluation of the overall contrast is a result of comprehensively judging the results of the dark room contrast and the bright room contrast and adopting the lower evaluation. At this time, the evaluation is a pass / fail evaluation by 7 people, “」 ”indicates a case where the pass is 4/7 or more,“ ◯ ”indicates a case where the pass is 0/7, and“ △ ”indicates a pass is 3 / This is a case of 7 or less, and “x” is a case where “No” is 4/7 or more.

(result)
The electromagnetic shielding materials of Comparative Examples 1 to 4 had insufficient contrast in the bright room where the fluorescent lamp was turned on, but the electromagnetic shielding materials of Examples 1 to 7 almost showed a decrease in the bright room contrast visually. I couldn't.

It is a typical top view which shows an example of the electromagnetic wave shielding material of this invention. It is an enlarged view of the A-A 'cross section in FIG. It is typical sectional drawing which expands and shows a part of FIG. It is explanatory drawing of the cross-sectional area of the conductive layer cut | disconnected by the virtual surface parallel to a transparent base material. It is a perspective view which shows the space shape of the recessed part of the printing plate filled with an electroconductive composition. It is a schematic diagram which illustrates the aspect in which a protrusion pattern blocks external light. It is a schematic diagram which shows the example in which external light is blocked | interrupted by the protrusion pattern and does not enter into the opening part whole surface. It is a schematic diagram which shows the example in which external light is interrupted | blocked by the protrusion pattern to the center point of an opening part. It is a schematic diagram which shows the cross-sectional form of a protrusion pattern. It is process drawing which shows an example of the manufacturing method of the electromagnetic wave shielding material of this invention. It is a schematic block diagram of the apparatus which enforces the manufacturing method of this invention. It is a schematic block diagram of the apparatus which implements the transfer process which transfers an electroconductive composition on a primer layer. It is a schematic diagram which shows the form which fills the recessed part of the electroconductive composition in a recessed part with a primer layer, and the electroconductive composition transfers. It is typical sectional drawing which shows an example of the filter for displays of this invention. It is explanatory drawing of the conventional phenomenon which the non-transfer part of an electroconductive ink composition generate | occur | produces on a transparent base material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent base material 2 Primer layer 3 Conductive layer 3 'Conductive composition layer 4 Metal layer 5 Side edge 6 Recess 7 Electromagnetic wave shielding pattern part 8 Grounding part 9 Protective layer 10 Electromagnetic wave shielding material 12 Interface between primer layer and conductive layer 13 Ridge part 14 external light 15 conductive composition 16 conductive layer pattern 17 first peak 18 second peak 19, 19 'protruding pattern 20 one side 30 measurement sample piece 51 gravure roll 52 backup roll 53 resin composition filling container 54 Doctor blade 61 Pickup roll 62 Intaglio roll 63 Plate surface 64 Recess 65 Doctor blade 66 Nip roll 67 Nip roll 68 Filling container A A portion where a conductive layer is formed T _A A thickness B A portion where a conductive layer is not formed T _B B Thickness H Height of protruding pattern W Width of protruding pattern L Pitch length of outgoing pattern P Virtual plane Q Center point S1 A line where an imaginary line extending from an arbitrary point (for example, the center point) of the opening toward the top of the protruding pattern is in contact with the protruding pattern S2 Normal line of electromagnetic shielding material θ S1 Angle between line and S2 line

Claims (18)

An electromagnetic shielding material having a transparent substrate, a primer layer formed on the transparent substrate, and a protruding pattern including at least a conductive layer made of a conductive composition formed on the primer layer in a predetermined pattern Because
Of the primer layer, the portion where the conductive layer is formed is thicker than the portion where the conductive layer is not formed,
The cross-sectional area of the conductive layer constituting the protruding pattern cut by a virtual plane parallel to the surface of the transparent substrate is a decreasing function S (x) of the distance x from the transparent substrate, and the protruding pattern An electromagnetic wave shielding material, wherein at least the outermost surface of the side surface is blackened. When the line width of the protruding pattern is W, the pitch (line interval) of the protruding pattern is L, and the height of the protruding pattern is H, θ = tan ⁻¹ (((L−W) / 2 + (W The electromagnetic wave shielding material according to claim 1, wherein the angle θ indicated by / 2)) / H) is less than 87 ° (the height is a difference in thickness between the protruding pattern forming portion and the protruding pattern non-forming portion. ).   The electromagnetic wave shielding material according to claim 1 or 2, wherein a ratio (W / L) between a line width W of the protruding pattern and a pitch L of the protruding pattern is less than 0.15.   The electromagnetic wave shielding material according to claim 1, wherein the protruding pattern includes a metal layer formed on a surface of the conductive layer.   The electromagnetic wave shielding material according to any one of claims 1 to 4, wherein the primer layer is a layer made of an ionizing radiation curable resin or a thermoplastic resin.   The electromagnetic wave shielding material according to claim 1, wherein the resin contained in the conductive layer is a thermoplastic resin, an ionizing radiation curable resin, or a thermosetting resin.   The interface between the primer layer and the conductive layer is an interface between the resin that constitutes the primer layer and the resin or powder that constitutes the conductive layer, and is interleaved alternately. The electromagnetic wave shielding material according to item 1.   The area | region where the primer component contained in this primer layer and this electroconductive composition exist in the interface vicinity of the said primer layer and the said conductive layer exists, The any one of Claims 1-6. Electromagnetic shielding material.   The electromagnetic wave shielding material according to claim 1, wherein a primer component contained in the primer layer is present in the conductive composition constituting the conductive layer.   The protruding pattern is a pattern composed of a first peak made of the primer layer and a second peak made of the conductive composition formed above the middle of the first peak. The electromagnetic wave shielding material according to claim 1.   A display filter comprising the electromagnetic wave shielding material according to claim 1 and provided on a front side of the display. A method for producing an electromagnetic shielding material having a protruding pattern including at least a conductive layer formed in a predetermined pattern on one surface of a transparent substrate,
A transparent base material preparing step of preparing a transparent base material on which one primer layer capable of maintaining fluidity until cured is formed;
A plate surface having a concave portion having a predetermined pattern is formed, and an opening cross-sectional area of the concave portion cut by a virtual plane parallel to the surface of the plate surface is a decreasing function S (x) of the distance x from the surface. An intaglio plate preparation step for preparing a plate-like or cylindrical plate;
After applying a conductive composition capable of forming a conductive layer after curing on the plate surface, the conductive composition adhering to other than the inside of the concave portion is scraped to fill the concave portion with the conductive composition. A composition filling step;
The primer layer side of the transparent substrate after the transparent substrate preparation step and the concave side of the plate surface after the conductive composition filling step are pressure-bonded, and the primer layer and the conductive composition in the concave portion are void. A crimping process that closely adheres,
A primer layer curing step that cures the primer layer after the crimping step but does not completely cure the conductive composition;
A transfer step of peeling off the transparent substrate and the primer layer from the plate surface after the primer layer curing step, and transferring the conductive composition in the recesses onto the primer layer;
A conductive composition curing step of curing the conductive composition formed in a predetermined pattern on the primer layer to form a conductive layer after the transfer step;
When the protrusion pattern is blackened at least on the outermost surface, the line width of the protrusion pattern is W, the pitch (line interval) of the protrusion pattern is L, and the height of the protrusion pattern is H And θ = tan ⁻¹ (((L−W) / 2 + (W / 2)) / H), wherein the angle θ is less than 87 °. In the conductive composition filling step, the conductive composition is a composition that can form a conductive layer that can be electroplated after curing,
The manufacturing method of the electromagnetic wave shielding material of Claim 12 which has a plating process which electroplats a metal layer on the conductive layer formed in the predetermined pattern on the said primer layer after the said conductive composition hardening process. A method for producing an electromagnetic shielding material having a protruding pattern including at least a conductive layer formed in a predetermined pattern on one surface of a transparent substrate,
A transparent base material preparing step of preparing a transparent base material on which one primer layer capable of maintaining fluidity until cured is formed;
A plate surface having a concave portion having a predetermined pattern is formed, and an opening cross-sectional area of the concave portion cut by a virtual plane parallel to the surface of the plate surface is a decreasing function S (x) of the distance x from the surface. An intaglio plate preparation step for preparing a plate-like or cylindrical plate;
After applying a conductive composition capable of forming a conductive layer after curing on the plate surface, the conductive composition adhering to other than the inside of the concave portion is scraped to fill the concave portion with the conductive composition. A composition filling step;
The primer layer side of the transparent substrate after the transparent substrate preparation step and the concave side of the plate surface after the conductive composition filling step are pressure-bonded, and the primer layer and the conductive composition in the concave portion are void. A crimping process that closely adheres,
A simultaneous curing step of simultaneously curing the primer layer and the conductive composition after the crimping step;
A transfer step of peeling off the transparent base material and the primer layer from the plate surface after the simultaneous curing step and transferring the conductive composition in the recess as a conductive layer onto the primer layer, and
When the protrusion pattern is blackened at least on the outermost surface, the line width of the protrusion pattern is W, the pitch (line interval) of the protrusion pattern is L, and the height of the protrusion pattern is H And θ = tan ⁻¹ (((L−W) / 2 + (W / 2)) / H), wherein the angle θ is less than 87 °. In the conductive composition filling step, the conductive composition is a composition that can form a conductive layer that can be electroplated after curing,
The manufacturing method of the electromagnetic wave shielding material of Claim 14 which has a plating process which electroplats a metal layer on the conductive layer formed in the predetermined pattern on the said primer layer after the said transfer process.   16. The primer layer according to any one of claims 12 to 15, wherein the primer layer is a layer made of an ionizing radiation curable resin or a thermoplastic resin, and the fluidity of the primer layer is maintained by non-irradiation of ionizing radiation or heating. Manufacturing method of electromagnetic shielding material.   The electromagnetic wave shield according to any one of claims 12 to 16, wherein the conductive composition contains a conductive powder and a resin, and the resin is a thermoplastic resin, an ionizing radiation curable resin, or a thermosetting resin. A method of manufacturing the material.   The thickness of the part to which the said conductive composition was transcribe | transferred among the said primer layers after the said transfer process is thicker than the thickness of the part to which the said conductive composition is not transcribe | transferred. 2. A method for producing an electromagnetic wave shielding material according to item 1.

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