JP2013120590A - Structural material for touch panel and touch panel structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure for a capacitive touch panel, capable of being adapted to a large-size screen.SOLUTION: A set of two to six thin conductive metal wires each having a width of 1 to 10 μm is formed in a wave shape with intervals of 1.0 to 3.0 mm therebetween and in parallel with each other, thereby configuring a conductive line on one surface of a transparent film. The conductive metal wires of each set are electrically connected with each other in each conductive line, and the conductive lines compose an electrode substrate [A] in which a large number of conductive lines form a net-like pattern. In the same way, an electrode substrate [B] is configured on one surface of another transparent film. The electrode substrate [A] and the electrode substrate [B] are affixed with each other through an insulating transparent adhesive in such a manner that the surfaces of the substrates with the conductive metal wires formed face each other and that the direction in parallel with the wave shape of the conductive metal wires of one of the substrates is orthogonal to that of the other substrate. The conductive line of each set on the electrode substrate [A] and the electrode substrate [B] is electrically connected to a terminal at its end.

Description

  The present invention relates to a structural material for a touch panel. More specifically, the present invention relates to a structural material that can be advantageously used for a capacitive touch panel. The present invention also relates to a capacitive touch panel structure.

The touch panel has a relatively simple structure and is inexpensive, allows finger input, and the market is expanding due to its convenience. Various types of touch panels such as a resistance film type, a capacitance type, and an optical type have been proposed. Of these, the resistance film type and the capacitance type are dominant.
In particular, the capacitance type is rapidly increasing in the market centering on mobile phones, since multi-input is relatively easy. However, the capacitive touch panel currently on the market has a small display surface, and a large screen has not yet spread. One of the reasons is that the structural material suitable for the capacitance type is not sufficient to cope with a screen having a large electric characteristic.

  As a result of research conducted for the purpose of providing a touch panel structure material excellent in transparency and conductivity and suitable for a large screen, in particular, a touch panel structure material suitable for a capacitance type, the present inventor has obtained the present invention. It has been reached.

In light of the fact that it has recently become relatively possible to obtain an electrode substrate formed by arranging a large number of fine lines of conductive metal on the surface of a transparent film, the present inventor As a result of various investigations and researches on the shape and thinness of the lines and the arrangement of a large number of fine lines, a certain number of fine lines are arranged in parallel in a plurality of waveforms at regular intervals and 2 to 6 adjacent lines. It has been found that a plurality of conductive lines arranged as a set can be advantageously used as a structural material for a capacitive touch panel, particularly as a structural material for a large screen.
The present invention has been achieved on the basis of such investigation facts, and according to the present invention, the following structural materials for touch panels and capacitive touch panel structures [I] to [XII] are provided.

[I] (1) On one side of the transparent film (A), (a-1) a large number of conductive metal wires are formed in parallel with a waveform at intervals of 1.0 to 3 mm, (a-2) The conductive metal wire has a width of 1 to 10 μm, and (a-3) each conductive metal wire is a set of two to six adjacent conductive lines, forming a number of conductive lines, (A-4) The electrode substrate [A] and the transparent film in which each set of conductive lines has a meshed pattern of conductive metal wires so that the conductive metal wires are electrically connected to each other in each set (B-1) A large number of conductive metal wires are formed in parallel with the waveform at intervals of 1.0 to 3.0 mm on one side of (B), and (b-2) each conductive metal wire has a width (B-3) Each conductive metal wire is a set of two to six adjacent conductive lines, and a number of conductive lines are formed. (B-4) An electrode substrate in which each set of conductive lines has a meshed pattern with conductive metal wires such that the conductive metal wires are electrically connected to each other in each set [ B],
(2) The electrode substrate [A] and the electrode substrate [B] face each other on the surface on which the respective conductive metal wires are formed, and the directions parallel to the waveforms of the respective conductive metal wires are orthogonal to each other. So that it is bonded through an insulating transparent adhesive layer,
(3) The structural material for a touch panel, wherein the conductive lines in each set of the electrode substrate [A] and the electrode substrate (B) are electrically connected to terminals from the terminals of each set.

[II] The structural material according to [I], wherein the conductive metal wires in the conductive line are formed in a waveform and in parallel at equal intervals.
[III] The structural material according to [I], wherein the conductive metal wire has a width of 2 to 8 μm.
[IV] The structural material according to [I], wherein the conductive metal wire has a thickness of 0.1 to 5 μm.
[V] The structural material according to [I], wherein 3 to 5 adjacent conductive metal lines form a set of conductive lines.

[VI] The conductive metal wire is formed of a structure in which Cu, Ni, Al, Ag, Cr, an alloy composed of two or more of these, or a multilayer of these two or more metals is laminated. The structural material described.
[VII] The structural material according to [I], wherein the insulating transparent adhesive layer has a thickness of 50 to 300 μm.
[VIII] The structural material according to [I], wherein the transparent film is a polyethylene terephthalate film having a thickness of 50 to 300 μm.
[IX] The structural material according to [I], wherein the meshed conductive metal wire (netted wire) is corrugated and formed in a direction perpendicular to the direction of the parallel conductive metal wire.
[X] The structural material according to the above [I], which has an aperture ratio of 85% or more.
[XI] A capacitive touch panel structure formed of the structural material described in [I].
[XII] A static structure having a structure in which the surface of the touch panel structure composed of the structural material described in [I] is protected with a glass plate having a thickness of 0.5 to 4 mm or a transparent resin sheet having a thickness of 0.5 to 2 mm. Capacitive touch panel structure.

  In the structural material according to the present invention, a large number of fine conductive metal wires are formed on a surface of one side of a transparent film in a wavy shape and in parallel at regular intervals. Forming a line. Therefore, it has excellent transparency as a whole, and even if breakage or disconnection occurs in a part of the conductive metal wire, one conductive line is formed by a plurality of the metal wires, and the plurality of the metal wires are reticulated by the metal wires. In this case, the conductive line is not broken and the electrical connection is not broken. In addition, the conductive metal wires are corrugated and formed in parallel, and therefore have the effect of preventing the moire phenomenon. In addition, the fine conductive metal wire formed on the surface of the transparent film is excellent in conductivity and can capture a very small amount of capacitance with high sensitivity, and is therefore suitable as a structural material for a capacitive touch panel. It is particularly suitable for a structural material for a capacitive touch panel having a large screen.

FIG. 1 schematically shows a plan view of an electrode substrate constituting the structural material for a touch panel of the present invention.

Hereinafter, the structural material for a touch panel of the present invention will be described with reference to the drawings.
FIG. 1 schematically shows a plan view of an electrode substrate constituting the structural material for a touch panel of the present invention. In FIG. 1, [A] indicates an electrode substrate [A], and [B] indicates an electrode substrate [B]. As will be described later, the electrode substrates [A] and [B] have substantially the same pattern on one side of the transparent film. However, the two substrates do not have to have the same pattern.

  The electrode substrates [A] and [B] in the present invention are each formed by forming a large number of conductive metal wires in a wavy shape and in parallel on one side of a transparent film. The transparent film may be a resin film that has excellent transparency, and examples thereof include a polyester film, a polycarbonate film, a polyolefin film, and a polycycloolefin film, but a polyester film is preferable. Specifically, a polyethylene terephthalate (PET) film or a polyethylene-2.6-naphthalate (PEN) film is preferable, and a polyethylene terephthalate (PET) film is particularly preferable. A biaxially stretched transparent film is preferably used, and the thickness is suitably 50 to 300 μm, particularly preferably 80 to 250 μm.

  First, the electrode substrate [A] will be described. On the surface of one side of the transparent film (A), a large number of conductive metal wires are formed in a waveform and in parallel. That is, in FIG. 1, a plurality of corrugated conductive metal lines are formed in parallel in the horizontal direction in the drawing. A large number of conductive metal lines adjacent to each other, preferably 2 to 6, preferably 3 to 5, are combined into one set to form one conductive line. In FIG. 1, three conductive metal wires are combined to form one conductive line. A set of conductive lines is indicated by X-1, X-2, X-3, X-4... Xn.

  A large number of conductive metal lines are formed in parallel with the corrugation. The shape of the corrugation will be described below. In one metal line, between the peaks and peaks in the corrugation (that is, two adjacent vertices and apexes). The length of the straight line) is 1 to 12 mm, preferably 2 to 10 mm. Also, the width between peaks and valleys in the waveform (that is, the width of a parallel line formed by connecting a line connecting two adjacent vertices and a line connecting the two adjacent bottom points) is 1 to 6 mm, preferably 1.5 to 5 mm is suitable. Many conductive metal lines are formed in a waveform and in parallel, but it is desirable that the center line of the waveform is formed in a substantially straight line. Further, “formed in parallel with the waveform” means that the shape of each waveform of the conductive metal line is the same in each set of conductive lines.

  Each set of conductive lines forms a mesh pattern with conductive metal lines so that the conductive metal lines are electrically connected to each other in each set. That is, in FIG. 1, the conductive metal wires that are reticulated are indicated by dotted lines for the sake of explanation. Hereinafter, the conductive metal line indicated by the dotted line may be abbreviated as “reticulated line”. In FIG. 1A, the dotted mesh lines are shown only at the left and right ends for the sake of explanation, but are also present in the middle. The reticulated lines are formed in a ladder shape with respect to the directions of a large number of parallel metal lines in FIG. However, although it is preferable that the reticulated line is perpendicular to the arrangement direction of the parallel corrugated metal lines, it is not always necessary. It may be reticulated at a certain angle, and it is necessary that the reticulated wires are electrically connected to each other (conductive lines). It is important that one set is connected to form one conductive line, and one set and the other set are not electrically connected. That is, there is no reticulated line between sets.

The reticulated wires in each set function to maintain the electrical connection of each set of conductive lines when the conductive metal wires are partially or locally damaged or broken . The number of reticulated wires is 1 to 5 wires, preferably 2 to 5 wires per set with respect to 10 mm in the length direction of the conductive metal wires.
The conductive metal wire desirably has a width of 1 to 10 μm, preferably 2 to 8 μm, and a thickness of 0.1 to 5 μm, preferably 0.1 to 4 μm. The width and thickness of the reticulated line are selected from the same range as that of the conductive metal line.
The conductive metal wire and the mesh wire are made of a conductive metal material, specifically, Cu, Ni, Al, Ag, Cr, an alloy composed of two or more of these metals, or a multilayer of these metals. And those formed with different structures. Of these, Cu and Ag are preferable, and Cu is particularly advantageous in terms of workability and price.

The electric board [A] is a set of 2 to 6 conductive metal wires, and one conductive line (X-1, X-2, X-3, X-4,... Xn ) Is formed. It is desirable that the number of conductive metal wires in each group is the same. In FIG. 1, one set of three conductive metal wires is formed. The distance between the conductive metal wires in each set (the distance between the center line of the corrugation and the center line) is 1.0 to 3 mm, preferably 1.5 to 2.5 mm, and is arranged in parallel with the corrugation. . The distance between the conductive metal lines is preferably equal within the above range.
The number of conductive metal lines in each set is desirably the same number, and the distance between the conductive metal lines in each set is preferably the same value. However, it is desirable that the distance between the pair is 1.5 to 10 mm, preferably 2 to 8 mm, and the distance between the pair is equal.

The conductive metal wire and the reticulated wire can be formed on one side of the transparent film by photoresist processing or photo edging processing. For the conductive metal wires formed on the surface of the transparent film, the distance between the metal wires in the set and the interval between the sets are the same value (equal intervals). This is advantageous in terms of control.
Although the electrode substrate [A] has been described with reference to FIG. 1, the electrode substrate [B] also has a conductive metal wire material, a corrugated shape, a line width, as shown in FIG. The thickness, the number and interval of conductive metal wires in a set, and the form and number of meshed wires are selected from the range described in the electrode substrate [A].

In FIG. 1, in the electrode substrate [B], a large number of conductive metal wires are formed in a vertical and corrugated shape in parallel, each set of conductive lines is composed of three conductive metal wires, and each set is Y-1. , Y-2, Y-3, Y-4, and Yn, which are understood as described below when the electrode substrate [A] and the electrode substrate [B] are bonded together. Because.
The electrode substrate [B] may be formed by disposing conductive metal wires and reticulated wires on the transparent film surface independently of the electrode substrate [A].
In the structural material for a touch panel of the present invention, the surfaces of the electrode substrate [A] and the electrode substrate [B] on which the respective conductive metal wires are formed face each other and the respective conductive metal wires are parallel to each other. It is laminated so that the directions are orthogonal (so that the corrugated center line is perpendicular), and both substrates are insulating transparent adhesive layers so that both conductive metal wires do not make direct electrical contact It is pasted through.

Referring to FIG. 1, when the electrode substrate [A] and the electrode substrate [B] are bonded together in a state where they are folded inward and centered around a dot-and-dash line indicated by ZZ ′, the conductive metal of both substrates The parallel arrangement of the lines becomes almost orthogonal.
The touch panel structural material of the present invention has a three-layer structure in which the electrode substrates [A] and [B] are bonded together with an adhesive layer as described above. The terminals of the conductive lines in each set on both boards are electrically connected to the terminals, but the connection lines from the terminals to the terminals are not shown in FIG. Each set is electrically connected to the controller via a terminal.

As the transparent adhesive, an adhesive that is insulative and can adhere a transparent film can be used. Examples thereof include vinyl acetate resin adhesives, ethylene / vinyl acetate resin adhesives, acrylic resin adhesives, synthetic rubber adhesives, and silicone resin adhesives. Of these, an acrylic resin adhesive is preferable, and an adhesive generally called OCA (Optical Clear Adhesive) is advantageously used.
The structural material of the present invention has an aperture ratio of 85% or more, preferably 87 to 98%, particularly preferably 88 to 96%. If the aperture ratio is less than 85%, the light transmittance is undesirably low. Here, the aperture ratio is the total area occupied by the conductive metal wires (including the meshed lines), where 100 is the real area of the region where the conductive metal wires are formed in the plan view of the surface of the structural material. This is the ratio of the area that is excluded.

As described above, the structure of the present invention has a structure in which the electrode substrate [A] / transparent adhesive layer / electrode substrate [B] are stacked in this order. It is preferable that the surface of the structure is further protected with a glass plate or a transparent resin sheet.
The glass plate preferably has a thickness of 0.5 to 4 mm, and the transparent resin sheet has a thickness of 0.5 to 2 mm. Examples of such a transparent resin include polycarbonate, acrylic resin, polyolefin, and polycycloolefin, and polycarbonate is excellent.
The structural material for a touch panel of the present invention is suitable as a member of a capacitive touch panel. In particular, the conductive metal wires formed on the electrode substrates [A] and [B] are excellent in conductivity and are reticulated even if they are fine or partially broken or disconnected, so a set of conductive lines. This is advantageous as a touch panel material for large images.

Claims (12)

(1) On one side of the transparent film (A), (a-1) a large number of conductive metal wires are formed in parallel with a waveform at intervals of 1.0 to 3 mm, and (a-2) each conductive metal The wire has a width of 1 to 10 μm, and (a-3) each conductive metal wire is a set of two to six adjacent conductive lines, forming a number of conductive lines, (a− 4) Each set of conductive lines includes an electrode substrate [A] and a transparent film (B) that form a meshed pattern of conductive metal wires so that the conductive metal wires are electrically connected to each other in each set. (B-1) A large number of conductive metal wires are formed in parallel and corrugated at intervals of 1.0 to 3 mm, and (b-2) each conductive metal wire has a width of 1 to 10 μm. Yes, (b-3) 2-6 adjacent conductive metal wires form a set of conductive lines to form a number of conductive lines. (B-4) Each set of conductive lines is composed of an electrode substrate [B] forming a meshed pattern with conductive metal wires so that the conductive metal wires are electrically connected to each other in each set. ,
(2) The electrode substrate [A] and the electrode substrate [B] face each other on the surface on which the respective conductive metal wires are formed, and the directions parallel to the waveforms of the respective conductive metal wires are orthogonal to each other. And (3) the conductive lines in each group of the electrode substrate [A] and the electrode substrate [B] are electrically connected from the terminals of the respective groups. It is connected to the,
A structural material for touch panels. 2. The structural material according to claim 1, wherein the conductive metal lines in the conductive line are formed in a waveform and in parallel at equal intervals. The structural material according to claim 1, wherein the conductive metal wire has a width of 2 to 8 μm. The structural material according to claim 1, wherein the conductive metal wire has a thickness of 0.1 to 5 μm. The said conductive metal wire is a structural material of the said Claim 1 in which 3-5 adjacent forms the set of conductive lines. 2. The conductive metal wire, Cu, Ni, Al, Ag, Cr, an alloy composed of two or more of these metals, or a structure laminated with a multilayer of these two or more metals. Structural material. The structural material according to claim 1, wherein the insulating transparent adhesive layer has a thickness of 50 to 300 μm. The structural material according to claim 1, wherein the transparent film is a polyethylene terephthalate film having a thickness of 50 to 300 μm. 2. The structural material according to claim 1, wherein the meshed conductive metal wire (meshing wire) is formed in a direction perpendicular to the direction of the conductive metal wire which is corrugated and parallel. The structural material according to claim 1, which has an aperture ratio of 85% or more. A capacitive touch panel structure made of the structural material according to claim 1. A capacitive touch panel having a structure in which the touch panel structure formed of the structural material according to claim 1 is surface protected with a glass plate having a thickness of 0.5 to 4 mm or a transparent resin sheet having a thickness of 0.5 to 2 mm. Structure.

Images