JP2012164552A - Method of manufacturing conductive pattern formation substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method in which a conductive pattern formation substrate having a three-dimensional shape can be manufactured without shifting the position of a conductive pattern from a desired position.SOLUTION: The method is used for manufacturing the conductive pattern formation substrate 10 having the three-dimensional shape comprising: an insulating substrate 11; and a conductive film 12 having a conductive part C which is provided on the insulating substrate 11 and has metal-made mesh-like members disposed in a base material, and an insulating part I in which cavities formed by removing the mesh-like members in the base material are disposed. This method includes: a step of obtaining a substrate 18 for molding formed by forming at least a base film a having the mesh-like members disposed in the base material on the insulating substrate 11; a step of making a three-dimensional shaped substrate 20 by molding the substrate 18 for molding into the three-dimensional shape; and a step in which cavities are formed by irradiating the base film a with laser beam L in the three-dimensional shaped substrate 20, thereby making the conductive film 12.

Description

  The present invention relates to a method for manufacturing a conductive pattern forming substrate used as an electrode sheet or the like of a capacitance type or membrane type input device (touch sensor).

  As input devices for home appliances, mobile phones, personal computers, automobiles, etc., instead of conventional mechanical buttons, switches, etc., an approach operation or a contact operation (sliding operation) using an input body such as a user's finger is included. Capacitance type or membrane type input devices, that is, so-called touch sensors, that detect information on the operation and input information based on the operation to an electronic device or the like are attracting attention. As an electrode sheet in the touch sensor, a conductive pattern forming substrate in which a conductive pattern is formed on the surface of an insulating substrate is used.

  By the way, in the touch sensor, in order to make the touch sensor follow the shape of the place where the touch sensor is installed without a gap, or to give the touch sensor the same three-dimensional design as a conventional button or switch, In some cases, the touch sensor is required to have a three-dimensional shape instead of a two-dimensional shape (plane). Therefore, in such a case, it is necessary to shape the conductive pattern forming substrate used for the touch sensor into a three-dimensional shape.

  As a method for manufacturing a three-dimensional conductive pattern forming substrate, a two-dimensional (planar) conductive pattern forming substrate on which a conductive pattern is formed by printing or the like, or a laminate of the conductive pattern forming substrate and a decorative layer A method of three-dimensional molding (vacuum molding or pressure molding) has been proposed (see, for example, Patent Documents 1 and 2).

However, this method has the following problems.
When forming a two-dimensional (planar) substrate into a three-dimensional shape by vacuum forming or pressure forming, the position of the conductive pattern on the three-dimensional conductive pattern forming substrate obtained after the forming becomes a predetermined position on the touch panel. Thus, it is necessary to accurately adjust the position of the substrate with respect to the mold. However, in vacuum forming or pressure forming, it is difficult to accurately adjust the position of the substrate with respect to the mold. Therefore, in the three-dimensional shape conductive pattern forming substrate obtained after forming, the position of the conductive pattern is predetermined on the touch panel. May be displaced from the position.

JP 2010-244776 JP 2010-267607 A

  The present invention provides a method capable of manufacturing a conductive pattern forming substrate having a three-dimensional shape without shifting the position of the conductive pattern from a desired position.

  The conductive pattern forming substrate manufacturing method of the present invention includes an insulating substrate, a conductive portion provided on the insulating substrate, and a conductive member in which a mesh-like member made of a conductive metal is disposed in an insulating base, and the base. A conductive pattern forming substrate having a three-dimensional shape, comprising: a conductive film having an insulating portion in which a void formed by removing the mesh member in the body is disposed, the insulating substrate A step of obtaining a molding substrate having at least a base film on which the mesh member is disposed in the base, a step of three-dimensionally molding the molding substrate to obtain a three-dimensional shape substrate, Forming the voids by irradiating the base film on the three-dimensionally shaped substrate with laser light to form the conductive film.

  According to the method for manufacturing a conductive pattern forming substrate of the present invention, a conductive pattern forming substrate having a three-dimensional shape can be manufactured without shifting the position of the conductive pattern from a desired position.

It is sectional drawing which shows an example of the conductive pattern formation board | substrate in this invention. It is an enlarged photograph explaining the state of the electroconductive part of the electrically conductive film of the electrically conductive pattern formation board | substrate in this invention, and the base film before laser processing. It is an enlarged photograph explaining the insulation part of the electrically conductive film of the conductive pattern formation board | substrate in this invention. It is sectional drawing explaining an example of the manufacturing method of the conductive pattern formation board | substrate of this invention. It is a side view explaining an example of the manufacturing apparatus used for the manufacturing method of the conductive pattern formation board | substrate of this invention, and the irradiation method of a laser beam.

<Conductive pattern forming substrate>
FIG. 1 is a cross-sectional view showing an example of a conductive pattern forming substrate obtained by the manufacturing method of the present invention. The conductive pattern forming substrate 10 includes a dome portion in which a conductive film 12 having a conductive portion C and an insulating portion I is formed on an insulating substrate 11, a wiring connection portion in which a wiring line (not shown) is formed, and at least The decoration layer 14 which coat | covers the surface of the electrically conductive film 12 of a dome part, and the protective film 16 which coat | covers the surface of at least the decoration layer 14 are provided.

(Insulating base material)
As the insulating substrate 11, a substrate that can be molded by three-dimensional molding is used. Further, as the insulating substrate 11, it is preferable to use a substrate that has insulating properties, can form the conductive film 12 on the surface, and hardly changes in appearance under predetermined irradiation conditions with respect to laser processing described later. Specific examples include insulating materials such as polycarbonate, polyester typified by polyethylene terephthalate (PET), and acrylonitrile / butadiene / styrene copolymer resin (ABS resin). The insulating substrate 11 may be transparent or colored.

(Conductive part)
As shown in FIG. 2, the conductive portion C of the conductive film 12 includes a net member 3 made of a conductive metal in a base 2 having an insulating property. That is, the conductive portion C of the conductive film 12 is formed in the substrate 2 by holding the mesh member 3 which is an inorganic network member developed so as to extend along the surface direction perpendicular to the thickness direction.

As an insulator constituting the substrate 2, thermoplastic resin (polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polymethyl methacrylate, nitrocellulose, chlorinated polyethylene, chlorinated polypropylene, vinylidene fluoride), heat, ultraviolet light , Cured products of curable resins (unsaturated polyester resins, melamine acrylates, urethane acrylates, epoxy resins, polyimide resins, acrylic-modified silicates, etc.) that cure with electron beams, radiation, etc. A cured product of a curable resin is preferable because it can be filled (impregnated) between the metal ultrafine fibers 4 of the mesh member 3 in the state.
The insulating substrate 11 and the base 2 are preferably made of the same material or the same series of resin materials. Specifically, for example, when the insulating substrate 11 is a PET film, it is preferable to use a polyester-based resin for the base 2.

The net-like member 3 is composed of a plurality of metal microfibers 4 dispersed in the base 2 and electrically connected to each other.
Specifically, these metal microfibers 4 irregularly extend in different directions along the surface direction of the surface of the insulating substrate 11 (surface on which the conductive film 12 is formed), and at least a part thereof. These are arranged so densely that they overlap each other (contact each other), and are electrically connected (connected) to each other by such an arrangement.

  As a result, the mesh member 3 forms a conductive two-dimensional network on the surface of the insulating substrate 11, and a region where the mesh member 3 is disposed in the base 2 of the conductive film 12 is a conductive portion C. ing. Further, most of the metal microfibers 4 of the mesh member 3 are disposed below the surface of the conductive film 12 (surface facing away from the insulating substrate 11), but the portion embedded in the base 2. And a portion protruding from the surface of the substrate 2.

  Specific examples of the metal ultrafine fibers 4 include metal nanowires and metal nanotubes made of copper, platinum, gold, silver, nickel, and the like. In the present embodiment, metal nanowires (silver nanowires) mainly composed of silver are used as the metal microfibers 4. The metal ultrafine fibers 4 are formed, for example, with a diameter of about 0.3 to 100 nm and a length of about 1 μm to 100 μm.

  In addition, as the mesh member 3, there are ultrafine fibers other than the above-described metal ultrafine fibers 4, that is, fibrous members such as silicon nanowires, silicon nanotubes, metal oxide nanotubes, carbon nanotubes, carbon nanofibers, graphite fibrils, and the metal-coated members thereof. While being used, these may be configured to be dispersed and connected.

(Insulation part)
In the base 2 of the conductive film 12, at least a part of the mesh member 3 is removed to form an insulating portion I. That is, as shown in FIG. 3, a plurality of voids 5 are formed in the base 2 by removing the metal microfibers 4 of the mesh member 3, and regions where the voids 5 are densely arranged are formed. Insulating part I.

  The gap 5 has a long hole shape (an oblong hole shape) or a hole that irregularly extends or is scattered in different directions along the surface direction of the surface of the substrate 2 (the surface facing the side opposite to the insulating substrate 11). Each has a shape (round hole shape), and has a portion opening on the surface. Specifically, the gap 5 is disposed so as to correspond to the position where the removed metal microfiber 4 is disposed, and has a diameter (inner diameter) substantially equal to the diameter of the metal microfiber 4. It is formed below the length of the metal ultrafine fiber 4.

  More specifically, one metal microfiber 4 is completely evaporated / removed, or at least a part thereof is evaporated / removed so that the metal microfiber 4 is divided in the extending direction, A plurality of gaps 5 are formed at intervals. That is, a plurality of gaps 5 that are spaced apart from each other are formed so as to extend or be scattered so as to form a linear shape as a whole corresponding to the corresponding positions of the metal microfibers 4. Note that only one gap 5 may be formed so as to correspond to a corresponding position of one metal microfiber 4 so as to form a linear shape.

In the insulating portion I, by forming these voids 5, the metal microfibers 4 that are conductors are removed, and the mesh member 3 that is the conductive two-dimensional network is removed (disappeared). )
Thus, in the insulating part I, since the metal microfibers 4 are removed from the base 2, the conductive part C and the insulating part I in the base 2 (conductive film 12) have different chemical compositions. ing. Nevertheless, since the gap 5 corresponding to a corresponding position exists in the metal microfiber 4, the optical characteristics are not greatly different from each other, and it is possible to satisfy the two conditions of insulation and invisibility.

(Wiring line)
The wiring line (not shown) electrically connects the conductive portion C of the conductive film 12 to a detecting means (not shown) such as an interface circuit that detects an input signal.
Examples of the material for the wiring line include conductive metal materials such as silver and copper.

(Decoration layer)
The decoration layer 14 is formed by forming a decorative pattern, characters, figures, symbols, and the like on the surface of a film substrate by a known printing method.
Examples of the film substrate include PET, polyethylene naphthalate (PEN), polycarbonate, acrylic resin, and the like. The film substrate may be transparent or colored.

(Protective film)
The protective film 16 is made of a transparent material, and protects the surface of the decorative layer 14 and the wiring connection portion (not shown).
The protective film 16 includes a transparent adhesive material and a transparent film substrate; a film made of a cured curable resin having a property of being cured by ultraviolet rays, heat, electron beam, radiation, etc .; a film made of SiO ₂ A molded product having a plate shape or a three-dimensional shape made by injection molding or the like; and other known hard coat layers.
Examples of the film substrate include PET, PEN, polycarbonate, acrylic resin and the like.

(Other embodiments)
In addition, the conductive pattern formation board | substrate in this invention is not limited to the conductive pattern formation board | substrate 10 of the example of illustration, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, when the conductive pattern forming substrate 10 is used for a transparent touch panel, the decoration layer 14 may not be provided.
Further, the decorative layer 14 may be omitted, and the insulating substrate 11 may be printed, or the decorative layer may be provided on the insulating substrate 11 by lamination, transfer, or the like.

  Moreover, although the net-like member 3 is composed of the plurality of metal ultrafine fibers 4 dispersed in the base 2 and electrically connected to each other, the present invention is not limited to this. In other words, the net member 3 may be a wire grid formed by forming a conductive metal film in a lattice shape by etching or the like.

Moreover, you may add functional layers, such as adhesion, antireflection, a hard coat, and a dot spacer, to the conductive pattern formation board | substrate 10 arbitrarily. In the laser processing described later, when a laser having a wavelength such as a fundamental wave of a YAG laser or a YVO ₄ laser is around 1000 nm and an acrylic polymer is used as a functional layer, the functional layer is irradiated after laser irradiation from the viewpoint of appearance characteristics. Is preferably provided.

(Use)
Examples of the use of the conductive pattern forming substrate 10 include an electrode sheet in a capacitance sensor (such as a capacitance input device attached to a handle of an automobile) provided on the surface of a three-dimensional molded product.

  When the conductive pattern forming substrate 10 is used as a capacitance sensor, the capacitance sensor is connected to the conductive pattern forming substrate 10 (electrode sheet) and the conductive portion C of the conductive pattern forming substrate 10 via a wiring line (not shown). And detecting means electrically connected to each other. The detecting means applies a predetermined voltage as a detection signal to the conductive portion C at a predetermined cycle, and conducts the input body and the conductive material when an approaching operation or a contact operation is performed on the surface of the protective film 16 by the input body. And a detection circuit that detects a change in capacitance with the part C as a change in the waveform of the detection signal.

  Further, when the decorative layer 14 is not provided and the insulating substrate 11 is transparent, since the conductive film 12 is transparent, the entire conductive pattern forming substrate 10 is also transparent. As an application of the conductive pattern forming substrate 10 in such a case, for example, a conductive pattern is formed in a transparent portion such as a transparent input device such as a transparent antenna, a transparent electromagnetic wave shield, a capacitance type or a membrane type transparent touch panel. Article to be used. In the present embodiment, “transparent” refers to a material having a light transmittance of 50% or more.

  When the conductive pattern forming substrate 10 is used for a membrane-type touch panel, the touch panel includes a pair of input members provided so that the conductive pattern forming substrate 10 (electrode sheet) is laminated in the thickness direction, and the conductive pattern forming substrate 10. And a detection unit such as an interface circuit that detects an input signal and is electrically connected to the conductive part C of the conductive film 12 via a wiring line (not shown).

<Method for producing conductive pattern forming substrate>
Next, the manufacturing method of the conductive pattern formation board | substrate of this invention is demonstrated using FIG. 4 and FIG.

  The method of manufacturing the conductive pattern forming substrate 10 includes a step of obtaining a molding substrate 18 in which at least a base film a on which the mesh member 3 is arranged in the base 2 is formed on the insulating substrate 11, and a molding substrate 18. A method comprising a step of three-dimensionally forming a three-dimensionally shaped substrate 20 and a step of forming a gap 5 by irradiating the base film a in the three-dimensionally shaped substrate 20 with a laser beam L to form a conductive film 12. It is.

Specifically, the conductive pattern forming substrate 10 is manufactured through the following steps (a) to (h), for example.
(A) A step of forming a base film a on the insulating substrate 11 to obtain a molding substrate 18.
(B) A step of forming a resist film (not shown) on the base film a in the region corresponding to the dome.
(C) A step of removing the resist film (not shown) after removing the base film a of the wiring connection portion (not shown) by etching.
(D) A step of forming a wiring line (not shown) electrically connected to the base film a (the conductive part C of the conductive film 12) on the insulating substrate 11 of the wiring connection part (not shown).
(E) A step of forming the three-dimensional shaped substrate 20 by three-dimensionally forming the forming substrate 18 and forming a dome portion.
(F) The process of forming the space | gap 5 by irradiating the base film a of a dome part with the laser beam L, and setting it as the electrically conductive film 12. FIG.
(G) The process of providing the decoration layer 14 on the electrically conductive film 12 at least.
(H) The process of providing the protective film 16 on the decoration layer 14 at least.

(Process (a))
As shown in FIG. 4, first, a base film “a” in which the mesh member 3 is disposed in the base 2 is formed in a region corresponding to the dome portion on the insulating substrate 11 and a wiring connection portion (not shown). The base film a is a conductive coating film having the same configuration as the conductive part C of the conductive film 12 shown in FIG. For example, the net member 3 is formed by dispersing and arranging the metal microfibers 4 on the insulating substrate 11 through a process of applying ink (liquid) including the metal microfibers 4 on the insulating substrate 11. The base 2 is formed by filling a liquid curable resin between the metal ultrafine fibers 4 dispersedly arranged on the insulating substrate 11 and then curing the resin, and the mesh member 3 is formed in the base 2. Fixedly arranged.

(Step (b) to Step (c))
Next, a portion corresponding to the wiring connection portion (not shown) in the base film a on the insulating substrate 11 is removed using a process by photolithography.
Specifically, first, a resist film 50 is formed in a region corresponding to the dome portion on the base film a.
Next, after removing a portion of the base film a corresponding to the wiring connection portion (not shown) by etching, the resist film 50 is removed. As the etching, either wet etching or dry etching may be used.

(Process (d))
A wiring line (not shown) electrically connected to the base film a (the conductive part C of the conductive film 12) is formed on the insulating substrate 11 of the wiring connection part (not shown). Specifically, the wiring line prints a paste-like conductive metal material made of silver or copper on the insulating substrate 11 in the wiring connecting portion (not shown) and on a part of the base film a (peripheral edge). Alternatively, it is formed by depositing a conductive metal material made of silver or copper.

(Process (e))
Next, as shown in FIG. 4, the region corresponding to the dome portion of the molding substrate 18 is three-dimensionally formed to form the dome portion, thereby forming the three-dimensional shape substrate 20.
As the three-dimensional molding method, there is a so-called thermoforming method in which the molding substrate 18 is heated to be in a soft state and then pressed against a mold. Examples of the thermoforming method include a vacuum forming method and a pressure forming method.

(Process (f))
Next, as shown in FIG. 4, by irradiating the base film a of the dome portion of the three-dimensional shape substrate 20 with the laser light L, the gap 5 and the insulating portion I are formed. The conductive film 12 includes a conductive part C that is a part other than the insulating part I. When the insulating substrate 11 is transparent, the base film a may be irradiated with the laser light L from the insulating substrate 11 side through the insulating substrate 11.

More specifically, these gaps 5 evaporate and remove the metal microfibers 4 by irradiating the region of the mesh member 3 where the metal microfibers 4 are disposed with a laser beam L which is a pulsed laser of a short pulse as a laser beam. It is formed by doing.
By irradiating the mesh member 3, which is a two-dimensional network made of the metal microfibers 4, with the laser light L that is a short pulse laser, it is possible to efficiently insulate only by destroying a small number of portions of the mesh member 3. In addition, it is possible to form the insulating portion I having a plurality of gaps 5 that are separated from each other corresponding to the corresponding positions of the metal microfibers 4 by irradiation with the laser light L.

The short pulse means that the pulse width is set to 300 nsec or less, and preferably the pulse width is set to 70 nsec or less.
As this pulsed laser, for example, a YAG laser or a YVO ₄ laser can be used. When a YAG laser or YVO ₄ laser is used, a machine widely used as a processing machine having a pulse width of about 5 to 300 nsec can be used.

Here, the manufacturing apparatus 40 which irradiates the laser beam L and the irradiation method of the laser beam L will be described in detail with reference to FIG.
In the present embodiment, a method of irradiating the base film a of the dome with laser light L, which is a pulsed laser with a short pulse, in a predetermined pattern is used.

As shown in FIG. 5, the manufacturing apparatus 40 used for manufacturing the conductive pattern forming substrate 10 of the present embodiment includes a laser light generating unit 41 that generates the laser light L and a condensing unit that collects the laser light L. A condensing lens 42 such as a convex lens, and a stage 43 on which the three-dimensional substrate 20 having the base film a formed on the upper surface is placed.
Then, the laser light L is irradiated from the laser light generating means 41 to the base film a through the condenser lens 42 to form the insulating portion I and the conductive pattern on the base film a.

  As the laser light generating means 41 in the manufacturing apparatus 40, one that generates laser light (visible light or infrared laser light) having a wavelength of less than 2 μm and a pulse width of less than 200 nsec is used. When the laser beam L having a pulse width of 1 to 200 nsec is used, it is easy to obtain the apparatus and reduce the equipment cost, which is preferable.

  The focal point F of the condenser lens 42 is set at a position away from the base film a. Specifically, the condenser lens 42 is disposed so that the focal point F of the laser light L is located between the base film a and the condenser lens 42. That is, in the manufacturing method of the conductive pattern forming substrate 10 of the present embodiment, the focal point F of the condenser lens 42 (laser light L) is disposed between the base film a to be processed and the condenser lens 42.

  The condensing lens 42 preferably has a low numerical aperture (NA <0.1). That is, by setting the numerical aperture of the condenser lens 42 to NA <0.1, it becomes easy to set the irradiation condition of the laser light L. In particular, the focal point F of the laser light L is between the base film a and the condenser lens 42. It is possible to prevent energy loss and diffusion of the laser light L due to the air plasma at the focal point F due to being positioned in between.

  Further, the base film a is formed by filling (impregnating) the base 2 made of resin between the fibers (element wires) of the net-like member 3 made of, for example, the metal ultrafine fibers 4, and the insulating substrate 11 made of a resin film. When provided above, the metal ultrafine fibers 4 embedded in the base 2 of the base film a can be reliably removed from the base 2 by the above setting. Accordingly, the gap 5 is surely formed corresponding to the desired shape of the insulating portion I. For example, a pattern such as a corner portion of a linear pattern that cannot be insulated unless it is conventionally set to a large R. However, the insulation process can be reliably and easily realized with a small R setting (or without providing R).

The stage 43 is configured to be movable two-dimensionally in the horizontal direction. The stage 43 is preferably composed of a member having at least a transparent upper surface or a member having light absorption.
When the insulating substrate 11 is transparent and the output of the laser beam L exceeds 1 W, the stage 43 is preferably made of a nylon-based or fluorine-based resin material or a silicone rubber-based polymer material.

A method of irradiating the base film a with the laser beam L using the manufacturing apparatus 40 having such a configuration is as follows.
First, the three-dimensionally shaped substrate 20 is placed on the upper surface of the stage 43 so that the base film a is disposed above the insulating substrate 11.

  Next, the laser beam L is emitted from the laser beam generator 41, and the laser beam L is collected by the condenser lens 42. The base film a is irradiated with a portion of the condensed laser light L where the spot diameter has passed through the focal point F. At that time, the stage 43 is moved so that the irradiation of the laser beam L has a predetermined pattern.

The energy density and the irradiation energy per unit area of the laser beam L irradiating the base film a vary depending on the pulse width of the laser.
For example, in a laser having a pulse width of 1 to 100 nsec (YAG laser or YVO ₄ laser), the energy density is 1 × 10 ^{11 to} 7 × 10 ¹³ W / m ² , and the irradiation energy per unit area is 1 × 10 ⁴ to 1. × 10 ⁶ J / m ² is preferable, and 1 × 10 ^{5 to} 3 × 10 ⁵ J / m ² is more preferable.
If the energy density / irradiation energy is set to a value smaller than the numerical range, the insulation of the insulating portion I may be insufficient. Moreover, when it is set to a value larger than the above numerical range, processing traces become conspicuous, which may be inappropriate for applications such as a transparent touch panel and a transparent electromagnetic wave shield.

These values are defined by dividing the output value of the laser beam in the processing area by the condensing spot area of the processing area. For convenience, the output is converted into the output value from the laser oscillator by the optical system. It is obtained by multiplying by the loss factor.
The spot diameter area S is defined by the following formula.
S = S ₀ × D / FL
S ₀ : Beam area of laser focused by lens FL: Focal length of lens D: Distance between surface (upper surface) of base film a and focal point

  The focal point F has been described by taking as an example a case where the light condensing means 42 such as a lens has sufficiently small aberration. However, for example, there is a spherical lens having a short focal length, an element that increases the aberration, such as a protective glass. In this case, the focal point F is defined as a position where the energy density of the condensing point is the highest.

  Here, the distance D is set within a range of 0.2% to 3% of the focal length FL. Preferably, the distance D is set within a range of 0.5% to 2% of the focal length FL. More preferably, the distance D is set within a range of 0.7% to 1.5% of the focal length FL. By setting the distance D within the numerical range, the metal ultrafine fibers 4 in the insulating portion I can be reliably removed (the formation of the gap 5) and an insulating pattern (conductive pattern) having high electrical reliability can be formed. In addition, it is possible to reliably prevent processing traces resulting from damage to the insulating substrate 11.

  Moreover, in the point which forms a highly accurate conductive pattern, it overlaps with adjacent spot positions by irradiating the pulsed laser beam L several times intermittently, moving the spot position on the base film a. It is preferable to form a part. Specifically, it is preferable to irradiate intermittently 3 to 500 times, and more preferably 20 to 200 times. If the irradiation is performed three times or more, the insulation can be more reliably performed. If the irradiation is performed 500 times or less, the portion of the substrate 2 irradiated with the laser light L can be prevented from being removed by dissolution or evaporation.

  In this way, by irradiating the base film a with the laser light L, an insulating portion I is formed by removing at least a part of the mesh member 3 in the base 2, and the insulating portion I and the base 2 are formed in the insulating portion I. The conductive pattern includes a conductive portion C on which the net member 3 is disposed. That is, the base film a is patterned to form the conductive film 12 having a conductive pattern composed of the conductive part C and the insulating part I.

(Process (g))
Next, as shown in FIG. 4, a decoration layer 14 is provided on at least the conductive film 12.
The decorative layer 14 is, for example, a decorative film in which a decorative pattern, characters, figures, symbols and the like are formed on the surface of the film base by a known printing method, by a known method such as vacuum pressure bonding, It is provided by laminating on the conductive film 12.

(Process (h))
Next, as shown in FIG. 4, a protective film 16 is provided on at least the decorative layer 14. The protective film 16 is preferably provided on the entire insulating substrate 11 of the wiring connection portion (not shown) so as to cover the wiring line (not shown) of the wiring connection portion (not shown).
The protective film 16 made of a film substrate can be provided, for example, by laminating a transparent film substrate on the conductive film 12 via a transparent adhesive material.
The protective film 16 made of a cured curable resin can be formed by, for example, applying a liquid curable resin on the conductive film 12 and curing it.
Protective film 16 made of SiO _2, for example, on the conductive film 12 can be formed by sputtering a SiO _2.

(Function and effect)
As described above, according to the method for manufacturing the conductive pattern forming substrate 10 according to the present embodiment, first, the entire surface (the region corresponding to the dome portion and the wiring connection portion) on the insulating substrate 11 is based on the initial stage of manufacture. A film a is formed. On the insulating substrate 11, the wiring connection portion (not shown) has a good workability because the base film a is removed extensively and rapidly using a photolithographic process.

  On the other hand, on the insulating substrate 11, a conductive pattern is formed on the dome portion by irradiating the laser beam L to form a conductive film 12. Specifically, in the base 2 of the conductive film 12, the arrangement region of the conductive mesh member 3 is the conductive portion C, and the arrangement region of the gap 5 formed by removing the mesh member 3 is the insulating portion I. Yes. That is, in the conductive part C, conduction is ensured by the mesh member 3 made of metal, and in the insulating part I, an electrical insulation state is reliably obtained by the gap 5 formed by removing the mesh member 3. It is supposed to be.

That is, in a conductive film using conventional metal nanowires or the like, the net-like member 3 made of metal nanowires or the like dispersed in the substrate 2 and electrically connected to each other remains not only in the conductive part C but also in the insulating part I. Therefore, it is difficult to reliably insulate the insulating portion I because the divided mesh member 3 is actively left in the insulating portion I so that the pattern is difficult to be visually recognized. It was.
On the other hand, according to the configuration of the present embodiment, the mesh member 3 (metal microfiber 4) of the insulating portion I is removed so as to replace the gap 5, and the insulating portion I and the conductive portion C have a chemical composition with each other. Is different. Thereby, since the insulation part I is reliably insulated, the electrical characteristic (performance) in the electrically conductive film 12 is stabilized, and the reliability as a product (input device) is improved.

  Further, in the insulating portion I, the mesh member 3 is removed to form a void 5 having a shape corresponding to (corresponding to) the mesh member 3 (metal microfiber 4). That is, since the gap 5 is formed, the conductive portion C and the insulating portion I are similar in color tone and transparency to each other and are not discriminated (viewed) from each other by the naked eye. . Therefore, even if the width of the insulating portion I is increased, the conductive pattern is not visually recognized.

  Further, since the mesh member 3 is composed of metal ultrafine fibers 4 dispersed in the substrate 2 and electrically connected to each other, the mesh member 3 uses commercially available metal nanofibers or metal nanotubes 4 such as metal nanotubes. And can be formed relatively easily.

  Further, as in this embodiment, when the metal fine fiber 4 having silver as a main component is used, the metal fine fiber 4 can be obtained relatively easily and used as the mesh member 3. Moreover, when removing the mesh member 3 (metal fine fiber 4) of the insulating part I by laser processing, a commercially available general laser processing machine can be used. Further, the metal microfiber 4 mainly composed of silver is more preferable because it can form a colorless and transparent conductive pattern having a high light transmittance and a low surface resistivity.

Specifically, according to the method for manufacturing the conductive pattern forming substrate 10, a general pulsed laser such as a YAG laser or a YVO ₄ laser is used as the laser light L, for example. An excellent conductive pattern forming substrate 10 can be easily manufactured.

  In laser processing of the base film a, the focal point F of the condenser lens 42 (laser light L) is provided at a position away from the base film a. Specifically, the focal point F is set to the base film a and the condenser lens 42. Since the laser beam L is radiated between them, the spot diameter of the laser beam L hitting the insulating substrate 11 becomes larger than the spot diameter of the laser beam L hitting the base film a. Thereby, the energy density of the laser beam L is ensured in the base film a and the insulating portion I is reliably formed, while the energy density of the laser beam L is reduced in the insulating substrate 11 to damage the insulating substrate 11. Can be prevented.

  Further, since the irradiation spot irradiated with the laser beam L on the base film a is formed in a planar shape instead of a spot shape, an irradiation energy density that does not affect the insulating substrate 11 while processing the base film a. This control becomes easier as compared with the conventional method. Furthermore, since it becomes possible to draw an insulating pattern with a large line width on the base film a in a lump, so-called filling processing becomes easy and the width of the insulating pattern can be increased, so that the insulating portion The insulating property of I is improved.

  In addition, the laser beam L is intermittently irradiated a plurality of times while moving the position of the spot on the base film a, and the insulating portion I is formed by overlapping the positions of adjacent spots. The conductive film 12 and the conductive pattern forming substrate 10 provided with a conductive pattern having excellent visual characteristics and good appearance can be obtained.

  Further, when the base 2 of the base film a and the insulating substrate 11 are made of the same material or the same type of resin material, the following effects are obtained. That is, since the absorbance of the laser light L in the base 2 of the base film a and the absorbance of the laser light L in the insulating substrate 11 are substantially the same, the energy density of the laser light L in the base film a is sufficiently secured. However, the energy density of the laser light L in the insulating substrate 11 can be reduced, and the above-described effects can be obtained with certainty. In addition, the base film a (conductive film 12) is easily firmly bonded onto the insulating substrate 11.

  Further, the net-like member 3 is formed by disposing and arranging the metal microfibers 4 on the insulating substrate 11 through a process of applying an ink (liquid) containing the metal microfibers 4 on the insulating substrate 11. . Further, the net member 3 is held in the substrate 2 by filling the liquid substrate 2 (liquid member) between the metal microfibers 4 dispersedly arranged on the insulating substrate 11 and then curing the substrate. Therefore, the following effects are produced. That is, the mesh member 3 can be easily provided in the base film a on the insulating substrate 11, and the metal microfibers 4 constituting the mesh member 3 are electrically and reliably connected to each other, so that the conductive portion C The electrical characteristics of are stable. Further, since the mesh member 3 is stably held by the base body 2, the above-described electrical characteristics extend the life.

  In addition, since the wiring line (not shown) is formed by printing or vapor-depositing a conductive metal material, the wiring line (not shown) reliably connects the conductive portion C of the conductive film 12 and the external circuit with low resistance. Connected to ensure electrical reliability. Further, since the wiring line (not shown) can be visually confirmed, it is possible to easily and quickly find out an abnormality or the like during manufacturing.

  Further, since the protective film 16 is provided at least on the conductive film 12, the conductive film 12 does not come into contact with the outside air and moisture, and migration and deterioration due to this contact can be reliably prevented. When the protective film 16 is provided over the entire area on the insulating substrate 11 as in this embodiment, it is more preferable because migration and deterioration of not only the conductive film 12 but also the wiring line (not shown) can be prevented.

  Then, after three-dimensionally forming the forming substrate 18 on which the base film a is formed on the insulating substrate 11, the gap 5 is formed by irradiating the base film a with the laser light L to form the conductive film 12. The position corresponding to the part I can be accurately irradiated with the laser light L. Therefore, the position of the conductive pattern does not deviate from the desired position.

  Thus, according to the method of manufacturing the conductive pattern forming substrate 10 of the present embodiment, it is easy to manufacture without forming the wiring connection portion, and the conductive pattern is not easily visible in the dome portion, and the appearance is excellent. In addition, a high-quality conductive film 12 can be formed, insulation of the insulating portion I of the conductive film 12 is sufficiently ensured, electrical reliability is improved, and the position of the conductive pattern is shifted from a desired position. There is no.

(Other embodiments)
In addition, the manufacturing method of the conductive pattern formation board | substrate of this invention is not limited to the above-mentioned embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.

  For example, when the decorative layer 14 is not provided, a transparent protective film 16 may be provided on the surface of the base film a before the three-dimensional molding (step (e)). In this case, in the laser processing (step (f)), the base film a may be irradiated with the laser beam L from the protective film 16 side through the protective film 16, and if the insulating substrate 11 is transparent, the insulating film 11 is insulated. The base film a may be irradiated with the laser light L from the substrate 11 through the insulating substrate 11.

  In the above-described embodiment, the focal point F of the laser beam L is arranged between the base film a and the condenser lens 42 in the laser processing (step (f)), but the present invention is not limited to this. is not. That is, it is only necessary to form the gap 5 by removing the mesh member 3 in the substrate 2 by irradiation with the laser beam L. Therefore, if the condition is satisfied, for example, the focal point F is focused on the base film a. You may arrange in.

In the above-described embodiment, the base film a is irradiated with the laser light L using a YAG laser or a YVO ₄ laser, but the type of the laser processing apparatus is not limited to the above. That is, any laser processing apparatus other than YAG laser and YVO ₄ laser may be used as long as the gap 5 can be formed by irradiation with the laser beam L.

  In the above-described embodiment, the patterning is performed by placing the insulating substrate 11 having the base film a on the movable stage 43 such as an XY stage, but the present invention is not limited to this. That is, for example, a method in which the insulating substrate 11 having the base film a is fixed and the condensing system member is relatively moved, a method in which the laser light L is scanned and scanned using a galvanomirror, or the like It is possible to perform patterning in combination.

  In addition, you may combine suitably the component demonstrated by the above-mentioned embodiment etc. of this invention. In addition, the above-described components can be replaced with well-known components without departing from the spirit of the present invention.

  Examples are shown below. The present invention is not limited to these examples.

[Example 1]
A 75 μm-thick PET film (Lumirror S10 # 75, manufactured by Toray Industries, Inc.) was coated with Cambrios's Ohm (trade name) ink (mixed solution containing silver fibers having a wire diameter of about 50 nm and a length of about 15 μm) and dried. After that, an ultraviolet curable polyester resin ink was overcoated, followed by drying and ultraviolet treatment. As a result, a base film a having a conductive two-dimensional network made of silver fibers was formed on the PET film, and a molding substrate 18 was obtained.

The forming substrate 18 was three-dimensionally formed into a dome shape as shown in FIG. 4 using a vacuum forming apparatus to obtain a three-dimensional shape substrate 20.
As a laser beam irradiation device, a YVO ₄ fundamental wave laser processing machine (manufactured by Keyence Corporation, MD-V9920) equipped with a galvanometer mirror was prepared.
The three-dimensionally shaped substrate 20 was placed on a polyacetal stage having a thickness of 5 mm, and irradiated with laser light L under the following irradiation conditions to provide an insulating pattern.
Distance from the focal point to the three-dimensional shape substrate 20: 0 mm
Output: 30%
Movement speed: 600mm / sec Oscillation frequency: 100kHz

  Thereby, the conductive pattern formation board | substrate with which the insulation part I was invisible was obtained. The conductive pattern was formed at a desired position. The electric resistance between the adjacent conductive parts C was 10Ω or more, and the insulation of the insulating part I was sufficiently ensured.

2 Substrate 3 Net member 4 Metal microfiber 5 Gaps 10 Conductive pattern forming substrate 11 Insulating substrate 12 Conductive film 18 Molding substrate 20 Three-dimensional substrate a Base film C Conducting portion I Insulating portion L Laser beam

Claims (1)

An insulating substrate;
A conductive portion provided on the insulating substrate, in which a mesh member made of a conductive metal is disposed in an insulating base, and a void formed by removing the mesh member in the base. A conductive film having an insulating portion to be disposed;
A method of manufacturing a conductive pattern forming substrate having a three-dimensional shape comprising:
Obtaining a molding substrate in which at least a base film on which the mesh member is disposed in the base is formed on the insulating substrate;
Three-dimensionally molding the molding substrate to form a three-dimensional shape substrate;
Forming the gap by irradiating the base film in the three-dimensional shape substrate with a laser beam to form the conductive film;
The manufacturing method of the conductive pattern formation board | substrate which has this.