JP5736183B2 - Manufacturing method of conductive pattern forming substrate - Google Patents

Description

  The present invention relates to a method for manufacturing a conductive pattern forming substrate provided on the front surface of an image display device, such as a touch panel and an electromagnetic wave shield of a plasma display.

In the touch panel, an input device having a conductive pattern forming substrate in which a transparent conductive film is formed on the surface of a transparent insulating substrate is installed as an electrode sheet on the front surface of an image display device such as a liquid crystal display.
This type of conductive pattern formation substrate includes an image display region (display region) where a transparent conductive film is formed and a low resistance wiring pattern formation region (wiring region) where a wiring line is formed on an insulating substrate. ing. The image display area is visible to the operator of the touch panel, and the low resistance wiring pattern formation area is covered with a decorative panel (frame) or the like and is not visible to the operator.

As a material constituting the transparent conductive film of the conductive pattern forming substrate, tin-doped indium oxide (ITO), π-conjugated conductive polymer (organic conductor) represented by polyethylenedioxythiophene-polystyrenesulfonic acid, or Known are those obtained by dispersing and curing conductive metal nanowires (metal ultrafine fibers) in an insulating resin binder (transparent substrate).
The transparent conductive film is provided with a plurality of conductive conductive parts formed in a wide range and an insulating insulating part formed so as to partition the conductive parts.

  In order to manufacture a conductive pattern forming substrate, first, a conductive base film is formed in the display region and the wiring region on an insulating substrate. Next, the base film is subjected to a photolithography process (resist film formation, etching process, resist film removal), and a portion of the base film corresponding to the insulating portion of the display region and the wiring region are formed. Remove. Next, a wiring line such as silver or copper is formed by printing or vapor deposition on the wiring region on the insulating substrate and a part (end portion) of the conductive portion of the display region (for example, Patent Documents 1 and 2 below). See).

However, the conventional conductive pattern forming substrate has the following problems.
That is, when a portion of the base film corresponding to the insulating portion of the transparent conductive film is removed by a photolithography process, the conductive pattern of the transparent conductive film is changed due to a difference in refractive index between the insulating portion and the conductive portion. It is visually recognized and is not preferable in appearance.

  As a method for producing a conductive pattern forming substrate in which the conductive pattern of the transparent conductive film is difficult to be visually recognized, a transparent conductive film is formed by using a base film in which metal microfibers are dispersed in a transparent substrate and irradiating the base film with laser light There has been proposed a method of cutting (disconnecting) a metal microfiber at a portion corresponding to the insulating portion and a metal microfiber in the wiring region into an electrically insulated state (see, for example, Patent Document 3 below).

However, this manufacturing method has the following problems.
In the base film in which the metal ultrafine fibers are dispersed in the transparent substrate, the metal ultrafine fibers are exposed from the surface, and therefore the metal ultrafine fibers are likely to be deteriorated due to oxidation or the like. And, since it takes a long time to form the insulating portion and the wiring region of the transparent conductive film by irradiating the base film with laser light, the metal microfibers of the base film deteriorate while irradiating the laser light. Therefore, the conductivity of the conductive part of the transparent conductive film that is finally formed is lowered.

JP 2008-83497 A JP 2010-20315 A JP 2010-44968 A

  The present invention has been made in view of such circumstances, and is capable of forming a high-quality transparent conductive film in which a conductive pattern is difficult to be visually recognized, and is capable of suppressing a decrease in conductivity of a conductive portion of the transparent conductive film. It aims at providing the manufacturing method of a pattern formation board | substrate.

In order to achieve the above object, the present invention proposes the following means.
That is, the present invention provides 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 transparent substrate, and the mesh member in the transparent substrate. Manufacturing a conductive pattern forming substrate comprising: a transparent conductive film having an insulating portion in which a void formed by removing a film is disposed; and an insulating protective film provided on the transparent conductive film A method comprising: forming a base film on which the mesh member is disposed in the transparent substrate on the insulating substrate; providing the protective film on the base film; and the protective film And providing the transparent film with the gap by irradiating the base film with laser light.
The protective film is preferably composed of an adhesive material and a resin film, and is provided so that the adhesive material is on the insulating substrate side.
The protective film is preferably a film made of a cured product of a curable resin or a film made of SiO ₂ .

  According to the manufacturing method of the conductive pattern formation board concerning the present invention, while being able to form a high quality transparent conductive film in which a conductive pattern is hard to be visually recognized, the fall of the conductivity of the conductive part of the transparent conductive film is suppressed.

It is a top view which shows the conductive pattern formation board | substrate which concerns on 1st Embodiment of this invention. It is a sectional side view in the XX cross section of FIG. It is an enlarged photograph explaining the state of the electroconductive part of the transparent conductive film of the conductive pattern formation board | substrate which concerns on 1st Embodiment of this invention, and the base film before laser processing. It is an enlarged photograph explaining the insulation part of the transparent conductive film of the conductive pattern formation board | substrate which concerns on 1st Embodiment of this invention. It is a sectional side view explaining the manufacturing method of the conductive pattern formation board | substrate which concerns on 1st Embodiment of this invention. It is a sectional side view explaining the manufacturing method of the conductive pattern formation board | substrate which concerns on 1st Embodiment of this invention. It is a side view explaining an example of the manufacturing apparatus used for manufacture of the conductive pattern formation board concerning a 1st embodiment of the present invention, and a laser beam irradiation method. It is a sectional side view which shows the conductive pattern formation board | substrate which concerns on 2nd Embodiment of this invention. It is a sectional side view explaining the manufacturing method of the conductive pattern formation board | substrate which concerns on 2nd Embodiment of this invention. It is a sectional side view explaining the manufacturing method of the conductive pattern formation board | substrate which concerns on 2nd Embodiment of this invention.

[First Embodiment]
Hereinafter, the manufacturing method of the conductive pattern formation board | substrate which concerns on 1st Embodiment of this invention, and the conductive pattern formation board | substrate produced by this are demonstrated with reference to FIGS.

<Conductive pattern forming substrate>
The conductive pattern forming substrate 10 of the present embodiment is applied to a product in which a wiring 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. can do. The conductive pattern forming substrate 10 is necessary for a capacitance sensor provided on the surface of a three-dimensional molded product or a three-dimensional decorative molded product, such as a capacitance input device attached to a steering wheel of an automobile. It can be used for the purpose of forming an electrode.

  When the conductive pattern forming substrate 10 of this embodiment is used for, for example, a touch panel (input device), the touch panel includes a pair of input members provided so that the conductive pattern forming substrate 10 is stacked in the thickness direction, and the conductive pattern forming substrate. And a detecting means such as an interface circuit that is electrically connected to a conductive portion C and a wiring line 14 of a transparent conductive film 12 (to be described later) and detects an input signal.

  As shown in FIGS. 1 and 2, the conductive pattern forming substrate 10 includes an image display region 13 (display region) in which a transparent conductive film 12 having a conductive portion C and an insulating portion I is formed on a transparent insulating substrate 11. ), And a low resistance wiring pattern forming region 15 (wiring region) in which the wiring lines 14 are formed, and a protective film 16 covering the surface of the image display region 13 and the low resistance wiring pattern forming region 15. The image display area 13 is visible from an operator such as a touch panel, and the low-resistance wiring pattern formation area 15 is covered with a decorative panel (frame) or the like and cannot be viewed from the operator.

In the present embodiment, “transparent” refers to a material having a light transmittance of 50% or more. The conductive pattern forming substrate 10 is transparent.
In FIG. 1, the description of the insulating portion I in the XX cross section is omitted, but actually, the conductive portion C is divided (partitioned) into the rectangular conductive portion C in FIG. Thus, the insulating portion I is formed to extend, for example, in a linear shape, and thereby the adjacent conductive portions C are electrically insulated from each other.

(Insulating base material)
As the insulating substrate 11, it is preferable to use an insulating substrate having an insulating property, capable of forming the transparent conductive film 12 on the surface, and hardly changing appearance under predetermined irradiation conditions with respect to laser processing described later. Specific examples include insulating materials such as glass, polycarbonate, polyester typified by polyethylene terephthalate (PET), and acrylonitrile / butadiene / styrene copolymer resin (ABS resin). As the shape of the insulating substrate 11, a plate-like material, a flexible film-like material, a three-dimensional (three-dimensional) molded product, or the like can be used depending on applications.

  When the conductive pattern forming substrate 10 is used for a transparent touch panel, a glass plate, a PET film, or the like is used for the insulating substrate 11. Further, when the conductive pattern forming substrate 10 is used as an electrode necessary for a capacitance sensor or the like such as a capacitance input device attached to a handle of an automobile, the insulating substrate 11 is a molded product made of ABS resin or the like. Alternatively, a decorative molded product provided with a decorative layer by laminating or transferring the film is used.

  For example, when the conductive pattern forming substrate 10 is used as a transparent touch panel such as a membrane input for bringing the two upper and lower electrode films (transparent conductive film 12) into contact with each other by pressing, the input person side insulating substrate 11 may be an input person. It is preferable to use a material that is flexible with respect to the external force from the side (for example, a transparent resin film). As the insulating substrate 11 on the image display device side opposite to the input user side, a conductive pattern is formed via a dot spacer. It is preferable to use a material having a predetermined or higher hardness that can easily support the substrate 10 (for example, equivalent to or higher than the insulating substrate 11 on the input side).

(Conductive part)
As shown in FIG. 3, the conductive portion C of the transparent conductive film 12 includes a mesh member 3 made of a conductive metal in a transparent base 2 having an insulating property. That is, the conductive portion C of the transparent conductive film 12 is formed in the transparent 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 transparent substrate 2, a transparent thermoplastic resin (polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polymethyl methacrylate, nitrocellulose, chlorinated polyethylene, chlorinated polypropylene, vinylidene fluoride), Examples include cured products of transparent curable resins (unsaturated polyester resins, melamine acrylates, urethane acrylates, epoxy resins, polyimide resins, silicone resins such as acrylic-modified silicates) that cure with heat, ultraviolet rays, electron beams, or radiation. A cured product of a curable resin is preferable because it can be filled (impregnated) between the strands (fibers) of the mesh member 3 in the previous liquid state.
The insulating substrate 11 and the transparent substrate 2 are preferably made of the same material or the same type of resin material. Specifically, for example, when the insulating substrate 11 is a PET film, it is preferable to use a polyester-based resin for the transparent substrate 2.

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

  Thereby, the mesh member 3 constitutes a conductive two-dimensional network on the surface of the insulating substrate 11, and the region where the mesh member 3 is disposed in the transparent base 2 of the transparent conductive film 12 is a conductive portion. C. Further, most of the metal microfibers 4 of the mesh member 3 are disposed under the surface of the transparent conductive film 12 (surface facing away from the insulating substrate 11), but are embedded in the transparent substrate 2. A portion and a portion protruding from the surface of the transparent 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 metal ultrafine fibers 4 described above, that is, fibrous members such as silicon nanowires, silicon nanotubes, metal oxide nanotubes, carbon nanotubes, carbon nanofibers, and graphite fibrils, and metal coated members thereof. While being used, these may be configured to be dispersed and connected.

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

  The gap 5 has a long hole shape (an oblong hole shape) that irregularly extends or is scattered in different directions along the surface direction of the surface of the transparent substrate 2 (the surface facing the side opposite to the insulating substrate 11) or Each has a hole 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 separated 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. Incidentally, only one gap 5 may be formed so as to form a linear shape corresponding to the corresponding position of one metal fine fiber 4.

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 transparent substrate 2, the conductive part C and the insulating part I in the transparent base 2 (transparent conductive film 12) are chemically different from each other. The composition is different. 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 14 electrically connects the conductive portion C of the transparent conductive film 12 to a detection means (not shown) such as an interface circuit that detects an input signal.
Examples of the material of the wiring line 14 include conductive metal materials such as silver and copper.

(Protective film)
The protective film 16 includes an adhesive material 17 and a resin film 18 and is provided so that the adhesive material 17 is on the insulating substrate 11 side.
Examples of the material of the resin film 18 include PET, polyethylene naphthalate, polycarbonate, acrylic resin, and the like.

<Method for producing conductive pattern forming substrate>
Next, the manufacturing method of the conductive pattern formation board | substrate 10 of this embodiment is demonstrated using FIGS. 5 and 6 show a manufacturing process in the XX cross section of FIG.

  The method of manufacturing the conductive pattern forming substrate 10 includes a step of forming a base film a in which the net-like member 3 is disposed in the transparent substrate 2 on the insulating substrate 11 and a protective film 16 on the base film a. And a step of forming the gap 5 by irradiating the base film a with the laser light L and providing the transparent conductive film 12 after providing the protective film 16.

Specifically, the conductive pattern forming substrate 10 is manufactured through the following steps (a) to (f), for example.
(A) A step of forming a base film a on the insulating substrate 11.
(B) A step of forming a resist film 50 on the base film a in the image display region 13.
(C) A step of removing the resist film 50 after removing the base film a in the low resistance wiring pattern forming region 15 by etching.
(D) A step of forming a wiring line 14 electrically connected to the conductive portion C of the transparent conductive film 12 on the insulating substrate 11 in the low resistance wiring pattern forming region 15.
(E) A step of providing the protective film 16 on at least the base film a.
(F) A step of forming the gap 5 by irradiating the base film a with the laser light L and providing the transparent conductive film 12 after providing the protective film 16.

(Process (a))
As shown in FIG. 5, first, a base film “a” in which the mesh member 3 is disposed in the transparent substrate 2 is formed in the image display region 13 and the low-resistance wiring pattern formation region 15 on the insulating substrate 11. The base film a is a conductive coating film having the same configuration as the conductive part C of the transparent 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 transparent base 2 is formed by filling a liquid curable resin between the metal microfibers 4 distributed on the insulating substrate 11 and then curing the resin, and the mesh member 3 is a transparent base. 2 is fixedly arranged.

(Step (b) to Step (c))
Next, a part corresponding to the low resistance wiring pattern formation region 15 is removed from the base film a on the insulating substrate 11 using a process by photolithography.
Specifically, first, as shown in FIG. 5, a resist film 50 is formed at a site corresponding to the image display region 13 on the base film a.
Next, as shown in FIG. 5, a portion of the base film a corresponding to the low resistance wiring pattern formation region 15 is removed by etching, and then the resist film 50 is removed. As the etching, either wet etching or dry etching may be used.

(Process (d))
As shown in FIG. 6, the wiring line 14 electrically connected to the conductive portion C of the transparent conductive film 12 is formed on the insulating substrate 11 in the low resistance wiring pattern forming region 15. Specifically, the wiring line 14 is a paste-like material made of silver or copper on the insulating substrate 11 in the low resistance wiring pattern forming region 15 and a part (periphery edge) on the conductive part C of the transparent conductive film 12. It is formed by printing a conductive metal material or depositing a conductive metal material made of silver or copper.

(Process (e))
Next, as shown in FIG. 6, an insulating protective film 16 is provided on at least the transparent conductive film 12. In the illustrated example, a resin film 18 is provided on the entire insulating substrate 11 via an adhesive material 17 so as to cover the transparent conductive film 12 and the wiring line 14, and a protective film 16 as a cover film is configured. Yes.

(Process (f))
Next, as shown in FIG. 6, the gap 5 is formed by irradiating the portion of the base film a corresponding to the image display region 13 with laser light L from the protective film 16 side through the protective film 16. In addition, an insulating portion I is formed to form a transparent conductive film 12 including the insulating portion I and a conductive portion C that is a portion other than the insulating portion 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 a YVO ₄ laser is used, a widely used 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 in the image display region 13 with a laser beam L, which is a short pulse laser beam, in a predetermined pattern is used.

As shown in FIG. 7, 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 insulating substrate 11 having the base film a and the protective film 16 formed thereon is placed.
Then, the laser beam L is irradiated from the laser light generating means 41 through the condenser lens 42 to the base film a from the protective film 16 side, thereby forming 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 transparent base 2 made of resin between the fibers (elementary wires) of the net-like member 3 made of, for example, the metal ultrafine fibers 4 and is made of an insulating resin made of a transparent resin film When provided on the substrate 11, the metal ultrafine fibers 4 embedded in the transparent substrate 2 of the base film a can be reliably removed from the transparent substrate 2 by the above setting. Therefore, the gap 5 is surely formed corresponding to the desired shape of the insulating portion I. For example, it is a pattern that cannot be insulated unless it is set to a large R conventionally, such as a corner portion of a linear pattern. 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 formed of a member having 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 insulating substrate 11 is placed on the upper surface of the stage 43 so that the base film a and the protective film 16 are 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. A portion of the condensed laser light L where the spot diameter has passed past the focal point F is irradiated to the base film a through the protective film 16. 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.
When the energy density / irradiation energy is set to a value smaller than the above 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

  In addition, although the focus F mentioned above demonstrated the case where the aberration was sufficiently small by the condensing means 42, such as a lens, for example, a spherical lens with a short focal distance, an element that increases aberration such as a protective glass, etc. When present, the focal point F is defined as the position where the energy density of the focal 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 above numerical range, it is possible to reliably remove the metal microfibers 4 (formation of the gap 5) in the insulating portion I and to form an insulating pattern (conductive pattern) having high electrical reliability. 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 transparent substrate 2 irradiated with the laser beam 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, the insulating part I is formed by removing at least a part of the mesh member 3 in the transparent base 2, and the insulating part I and the transparent base 2 are formed. A conductive pattern including a conductive portion C in which the mesh member 3 is disposed. That is, the base film a is patterned to form the transparent conductive film 12 having a conductive pattern composed of the conductive part C and the insulating part I.

  In the above description, the insulating substrate 11 having the base film a is placed on the movable stage 43 such as an XY stage for patterning. However, 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 focusing system member is relatively moved, a method in which the laser light L is scanned and scanned using a galvano mirror, or the like described above Patterning can be performed by combining them.

(Function and effect)
As described above, according to the method for manufacturing the conductive pattern forming substrate 10 according to this embodiment, first, the entire surface (the image display region 13 and the low-resistance wiring pattern forming region 15) on the insulating substrate 11 in the initial stage of manufacturing. The base film a is formed. On the insulating substrate 11, the low resistance wiring pattern formation region 15 that is not visually recognized by the operator is removed from the base film a in a wide range and quickly using a photolithography process, so that workability is good.

  On the other hand, on the insulating substrate 11, the image display region 13 visually recognized by the operator is formed with a transparent conductive film 12 by forming a conductive pattern by irradiating the laser beam L. Specifically, in the transparent substrate 2 of the transparent 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. Has been. 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 the conventional transparent conductive film, the mesh member 3 made of metal nanowires dispersed in the transparent substrate 2 and electrically connected to each other remains not only in the conductive part C but also in the insulating part I (insulation) Since the part of the mesh member 3 in the divided state is positively left in the part I so that the pattern is difficult to be visually recognized), it is difficult to reliably insulate the insulating part I.
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 insulated reliably, the electrical characteristic (performance) in the transparent 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 (wiring pattern) is not visually recognized.

  Further, since the mesh member 3 is composed of metal ultrafine fibers 4 dispersed in the transparent substrate 2 and electrically connected to each other, the mesh member 3 is made of metal ultrafine fibers 4 such as commercially available metal nanowires and 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, it becomes possible to draw an insulating pattern with a large line width on the base film a at once, so that the so-called filling process is facilitated and the width of the insulating pattern can be increased. 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 transparent conductive film 12 and the conductive pattern forming substrate 10 having a conductive pattern with excellent visual characteristics and good appearance can be obtained.

  Further, when the transparent 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 beam L in the transparent base 2 of the base film a and the absorbance of the laser beam L in the insulating substrate 11 are substantially the same, a sufficient energy density of the laser beam L in the base film a is ensured. 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 (transparent conductive film 12) is easily firmly bonded onto the insulating substrate 11.

  Further, the net-like 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. . In addition, by filling the liquid transparent substrate 2 (liquid member) between the metal ultrafine fibers 4 dispersed and arranged on the insulating substrate 11 in this way and then curing, the mesh member 3 is placed in the transparent substrate 2. Since it is held, 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. In addition, since the mesh member 3 is stably held by the transparent substrate 2, the above-described electrical characteristics extend the life.

  In addition, since the wiring line 14 is formed by printing or vapor-depositing a conductive metal material, the wiring line 14 reliably connects the conductive portion C of the transparent conductive film 12 and the external circuit with a low resistance. Reliability is ensured. In addition, since the wiring line 14 can be visually confirmed, it is possible to easily and quickly find out abnormalities during manufacturing.

  Moreover, since the insulating protective film 16 is provided at least on the transparent conductive film 12, the transparent conductive film 12 does not come into contact with the outside air and moisture, and migration and deterioration due to this contact are ensured. Can be prevented. When the protective film 16 is provided over the entire area on the insulating substrate 11 as in the present embodiment, it is more preferable because migration and deterioration of the wiring line 14 as well as the transparent conductive film 12 can be prevented.

  And after providing the protective film 16 on the base film a, since the space | gap 5 was formed by irradiating the base film a with the laser beam L, and it is set as the transparent conductive film 12, it exposed from the surface of the base film a The time during which the metal microfibers 4 are exposed to the outside air can be shortened as much as possible. Therefore, the metal ultrafine fiber 4 of the base film a is not deteriorated by the outside air while the laser beam L is irradiated, and the decrease in the conductivity of the conductive portion C of the finally obtained transparent conductive film 12 is suppressed.

  As described above, according to the method of manufacturing the conductive pattern forming substrate 10 of the present embodiment, the low resistance wiring pattern forming region 15 does not require time and effort, and the manufacturing is easy. It is possible to form a high-quality transparent conductive film 12 that is difficult to be visually recognized and has an excellent appearance, and the insulation of the insulating portion I of the transparent conductive film 12 is sufficiently ensured to improve the electrical reliability. A decrease in the conductivity of the conductive portion C of the film 12 can also be suppressed.

[Second Embodiment]
Next, a method for manufacturing a conductive pattern forming substrate according to the second embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same member as above-mentioned embodiment, and the description is abbreviate | omitted.

<Conductive pattern forming substrate>
As shown in FIG. 8, the conductive pattern forming substrate 10 includes an image display region 13 (display region) in which a transparent conductive film 12 having a conductive portion C and an insulating portion I is formed on a transparent insulating substrate 11; A low resistance wiring pattern formation region 15 (wiring region) in which the wiring lines 14 are formed, and a protective film 19 that covers the surface of the image display region 13 and the low resistance wiring pattern formation region 15 are provided.

(Protective film)
Examples of the protective film 19 include a film made of a cured product of a curable resin having a property of being cured by ultraviolet rays, heat, electron beam, radiation, and the like, a film made of SiO ₂ and the like.
By providing the protective film 19, the transparent conductive film 12 does not come into contact with the outside air or moisture as in the protective film 16 described above, and migration and deterioration due to this contact can be reliably prevented.

<Method for producing conductive pattern forming substrate>
The method of manufacturing the conductive pattern forming substrate 10 includes a step of forming a base film a on which the mesh member 3 is disposed in the transparent substrate 2 on the insulating substrate 11, and a protective film 19 on the base film a. And a step of forming the gap 5 by irradiating the base film a with the laser light L and providing the transparent conductive film 12 after providing the protective film 19.

Specifically, the conductive pattern forming substrate 10 is manufactured through the following steps (a) to (f), for example.
(A) A step of forming a base film a on the insulating substrate 11.
(B) A step of forming a resist film 50 on the base film a in the image display region 13.
(C) A step of removing the resist film 50 after removing the base film a in the low resistance wiring pattern forming region 15 by etching.
(D) A step of forming a wiring line 14 electrically connected to the conductive portion C of the transparent conductive film 12 on the insulating substrate 11 in the low resistance wiring pattern forming region 15.
(E) A step of providing a protective film 19 on at least the base film a.
(F) A step of forming the gap 5 by irradiating the base film a with the laser light L and providing the transparent conductive film 12 after providing the protective film 19.

(Process (a))
As shown in FIG. 9, first, a base film “a” in which the mesh member 3 is disposed in the transparent substrate 2 is formed in the image display region 13 and the low resistance wiring pattern forming region 15 on the insulating substrate 11.

(Step (b) to Step (c))
Next, a part corresponding to the low resistance wiring pattern formation region 15 is removed from the base film a on the insulating substrate 11 using a process by photolithography.
Specifically, first, as shown in FIG. 9, a resist film 50 is formed at a site corresponding to the image display region 13 on the base film a.
Next, as shown in FIG. 9, the portion corresponding to the low resistance wiring pattern formation region 15 in the base film a is removed by etching, and then the resist film 50 is removed.

(Process (d))
Next, as shown in FIG. 10, the wiring line 14 is formed on the insulating substrate 11 in the low resistance wiring pattern forming region 15 so as to be electrically connected to the conductive portion C of the transparent conductive film 12.

(Process (e))
Next, as shown in FIG. 10, an insulating protective film 19 is provided on at least the transparent conductive film 12.
The protective film 19 made of a cured product of a curable resin can be formed by, for example, applying a liquid curable resin on the transparent conductive film 12 and curing it.
Protective film 19 made of SiO _2, for example, the transparent conductive film 12 on, can be formed by sputtering a SiO _2.

(Process (f))
Next, as shown in FIG. 10, the gap 5 is formed by irradiating the portion of the base film a corresponding to the image display region 13 with the laser light L from the protective film 19 side through the protective film 19. In addition, an insulating portion I is formed to form a transparent conductive film 12 including the insulating portion I and a conductive portion C that is a portion other than the insulating portion 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.

(Function and effect)
According to the manufacturing method of the conductive pattern formation substrate 10 of this embodiment, the same effect as 1st Embodiment mentioned above is acquired.

Other Embodiment
In addition, 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, in the above-described embodiment, the insulating substrate 11 is transparent. However, the insulating substrate 11 may be colored with a certain degree of transparency.

  Further, although the net member 3 is composed of a plurality of metal ultrafine fibers 4 dispersed in the transparent substrate 2 and electrically connected to each other, the present invention is not limited to this. That is, the net member 3 may be a wire grid formed by forming a conductive metal film in a grid pattern by etching or the like.

In addition, functional layers such as adhesive, antireflection, hard coat, and dot spacer may be optionally added to the conductive pattern forming substrate 10.
In particular, when using a laser having a wavelength of about 1000 nm, such as a fundamental wave of a YAG laser or a YVO ₄ laser, and using an acrylic polymer material as the functional layer, it functions after laser irradiation from the viewpoint of appearance characteristics. It is preferable to provide a layer.

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

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. However, the type of the laser processing apparatus is not limited to the above. That is, any laser processing apparatus other than the YAG laser and the YVO ₄ laser may be used as long as the gap 5 can be formed by irradiation with the laser beam L.

  Further, the protective film 16 and the protective film 19 are not limited to those described in the above embodiment. For example, the protective film 16 and the protective film 19 may be used as a hard coat layer.

  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.

[Production Example 1]
On a 75 μm-thick PET film (Lumirror S10 # 75, manufactured by Toray Industries, Inc.), an Ohm (trade name) ink from Cambrios (a mixed solution containing silver fibers having a wire diameter of about 50 nm and a length of about 15 μm) is applied. After drying, a UV curable polyester resin ink was overcoated, followed by drying and UV treatment. Thereby, the base film a having a conductive two-dimensional network made of silver fibers was formed on the PET film. Furthermore, a 50 μm-thick PET film with an adhesive material 17 was stuck on the base film a to obtain a precursor substrate A.

[Example 1]
In this example, a YVO ₄ fundamental wave laser processing machine (manufactured by Keyence Corporation, MD-V9920) equipped with a galvanometer mirror was used as the laser beam irradiation apparatus.
Precursor substrate A of Production Example 1 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 focal point to precursor substrate A: 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 electric resistance between the adjacent conductive parts C was 1 MΩ or more, and the insulation of the insulating part I was sufficiently ensured. Moreover, the electrical resistance in the conductive part C was 100Ω or less, and the conductivity of the conductive part C was sufficiently ensured.

DESCRIPTION OF SYMBOLS 2 Transparent base | substrate 3 Net-like member 4 Metal microfiber 5 Space | gap 10 Conductive pattern formation board | substrate 11 Insulation board | substrate 12 Transparent conductive film 16 Protective film 19 Protective film a Base film C Conductive part I Insulating part L Laser beam

Claims (3)

An insulating substrate;
A conductive portion provided on the insulating substrate, in which a mesh member made of conductive metal is disposed in an insulating transparent substrate, and the mesh member in the transparent substrate is removed. A transparent conductive film having an insulating part in which a gap is disposed;
An insulating protective film provided on the transparent conductive film;
A method for producing a conductive pattern forming substrate comprising:
Forming a base film on the insulating substrate on which the mesh member is disposed in the transparent substrate;
Providing the protective film on the base film;
Forming the voids by irradiating the base film with laser light after providing the protective film, thereby forming the transparent conductive film;
The manufacturing method of the conductive pattern formation board | substrate which has this. The manufacturing method of the conductive pattern formation board | substrate of Claim 1 with which the said protective film consists of an adhesive material and a resin film, and the said adhesive material is provided so that it may become the said insulating substrate side. The protective film is a film made of a cured product of a curable resin or SiO ₂ The manufacturing method of the conductive pattern formation board | substrate of Claim 1 which is a film | membrane consisting of.