TW201314532A - Touch panel and method of fabricating touch panel - Google Patents

Abstract

A touch panel includes a plurality of first transparent conductive patterns extending along a first direction, a plurality of second transparent conductive patterns extending along a second direction perpendicular to the first direction, a plurality of first peripheral wirings electrically connected to each of the first transparent conductive patterns, and a plurality of second peripheral wirings electrically connected to each of the second transparent conductive patterns. The first and the second peripheral wirings, and the first and the second transparent conductive patterns are electrically connected through a U-shaped insulation film having one side opened. The first and the second transparent conductive patterns cover all of exposed parts of the first and second peripheral wirings exposed from the insulation film. By this way, the following touch panel is provided that good contacts (conductive) to the peripheral wirings can be achieved even in a contact area through a through hole formed in the insulation film, and further corrosion of the peripheral wirings can be prevented.

Description

Touch panel and touch panel manufacturing method

The present invention relates to a touch panel and a touch panel manufacturing method, and more particularly to a touch panel using a transparent conductive pattern including a binder and a conductive fiber.

Touch panels are attracting attention in recent years. The touch panel is mainly applied to a small-sized person such as a personal digital assistant (PDA) or a mobile phone, but it is considered to be large-sized by being applied to a display for a personal computer or the like.

As the transparent electrode of the touch panel, Indium Tin Oxide (ITO) was used. However, there is a problem that the price of indium which is a raw material of ITO is high and stable supply is limited, and a vacuum process is required to produce a film, which causes a high manufacturing cost, and the ITO film is brittle and has poor bending resistance.

Therefore, as a transparent electrode of a touch panel, a transparent conductive film containing metal thin wires (conductive fibers) has been studied. Patent Document 1 discloses that a transparent conductive film which is suitably manufactured by transferring a transparent conductive fiber layer onto a transparent film substrate, and which has high conductivity and good, is suitably used for a touch panel or the like. Transparency.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2009-231029

In an electronic device such as a touch panel, the electrode wires are electrically connected to each other via a through hole formed in the insulating film. However, in Patent Document 1, In the case of the described method, there is a problem in that contact between the electrode wires is insufficient in the contact region, and contact failure is not obtained to cause conduction failure.

The present invention has been made in view of such problems. An object of the present invention is to provide a touch panel which can be sufficiently integrated with a peripheral wiring in a contact region formed through a via hole formed in an insulating film even when a transparent conductive film is formed by transfer. Contact and good contact (conduction) with the surrounding wiring, thereby preventing corrosion of the surrounding wiring.

A touch panel according to one aspect of the present invention includes: a transparent substrate; a plurality of first transparent conductive patterns formed on the transparent substrate in a first direction and containing a binder and a conductive fiber; and a plurality of second transparent a conductive pattern formed on the transparent substrate in a second direction orthogonal to the first direction and including a binder and a conductive fiber; and a plurality of first peripheral wires formed on the transparent substrate and The end portions of the first transparent conductive patterns are electrically connected to each other, and the plurality of second peripheral wirings are formed on the transparent substrate and electrically connected to end portions of the second transparent conductive patterns. The first connection structure is And connecting the first transparent conductive patterns and the first peripheral wirings; and the second connection structure, wherein the second transparent conductive patterns and the second peripheral wirings are connected; the first connection structure includes the first periphery a U-shaped first insulating film formed on the first peripheral wiring and having an opening for exposing a part of the first peripheral wiring, and an upper surface of the exposed first peripheral wiring The first transparent conductive pattern, and a ratio of a thickness of the first insulating film to an opening length of the first insulating film (opening length of the first insulating film / first insulating) The film thickness of the film is 25 or more.

Further, in the touch panel of one aspect of the present invention, preferably, the second connection structure includes the second peripheral wiring, and is formed on the second peripheral wiring and has a portion for the second peripheral wiring a U-shaped second insulating film having an exposed opening, and a second transparent conductive pattern covering the exposed second peripheral wiring, and a thickness of the second insulating film and an opening length of the second insulating film The ratio (the opening length of the second insulating film / the film thickness of the second insulating film) is 25 or more.

It is preferable that the ratio of the film thickness of the first transparent conductive pattern to the film thickness of the first insulating film (the thickness of the first insulating layer / the film thickness of the first transparent conductive pattern) is 5 or more, 20 or less, and / The ratio of the film thickness of the second transparent conductive pattern to the film thickness of the second insulating film (the thickness of the second insulating layer / the film thickness of the second transparent conductive pattern) is 5 or more and 20 or less.

Preferably, the conductive fiber is a silver nanowire.

Preferably, the first peripheral wiring and the second peripheral wiring are formed of a metal film.

Preferably, the conductive fiber has a short axis of 50 nm or less.

According to another aspect of the present invention, a method of manufacturing a touch panel includes the steps of: forming a plurality of first peripheral wirings and a plurality of second peripheral wirings on a transparent substrate; and forming the first peripheral wirings on the first peripheral wirings a U-shaped first insulating film that opens an opening of a part of the first peripheral wiring, and/or a U-shaped opening having an opening for exposing a part of the second peripheral wiring to each of the second peripheral wirings a second insulating film having a shape; a conductive layer containing a binder and a conductive fiber formed on the transfer substrate; and transferring the conductive layer on the transfer substrate to the transparent substrate And covering the exposed portion of the first peripheral wiring and/or the second peripheral wiring, electrically connecting the first peripheral wiring and the second peripheral wiring to the conductive layer, and patterning the conductive layer And forming a plurality of first transparent conductive patterns extending in the first direction and a plurality of second transparent conductive patterns extending in the second direction orthogonal to the first direction.

Preferably, when the conductive layer on the transfer substrate is transferred onto the transparent substrate, the transparent substrate has a temperature range of 90 ° C or more and 120 ° C or less.

Preferably, when the conductive layer on the transfer substrate is transferred onto the transparent substrate, the transfer pressure is in a range of 0.4 MPa or more and 0.8 MPa or less.

According to the present invention, even when the transparent conductive film is formed by transfer, sufficient contact with the peripheral wiring can be achieved in the contact region, so that good contact (conduction) between the peripheral wiring and the transparent conductive film can be formed. Further, corrosion of the peripheral wiring can be prevented.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present invention has been described with reference to the preferred embodiments described below. However, other embodiments of the present embodiment can be utilized without departing from the scope of the invention. Accordingly, all changes that come within the scope of the invention are included in the scope of the patent application.

Hereinafter, the wiring structure and the touch panel of the present embodiment will be described with reference to FIGS. 1 to 3.

The touch panel 10 includes a transparent substrate 20 and is formed on the transparent substrate 20 The plurality of first transparent conductive patterns 30 and the plurality of second transparent conductive patterns 40. Each of the first transparent conductive patterns 30 is disposed along the first direction, and each of the second transparent conductive patterns 40 is disposed along a second direction orthogonal to the first direction.

The first transparent conductive pattern 30 includes a plurality of first sensing portions 32 and a first connecting portion 34 that electrically connects the plurality of first sensing portions 32 . The first sensing unit 32 has a rhombus shape having a large width, and the first connecting portion 34 has a reed shape having a small width. In the first transparent conductive pattern 30, the first sensing portion 32 and the first connecting portion 34 are integrally formed.

The second transparent conductive pattern 40 includes a plurality of second sensing portions 42 and a second connecting portion 44 that electrically connects the plurality of second sensing portions 42 . The second sensing unit 42 has a rhombus shape having a large width, and the second connecting portion 44 has a narrow strip shape having a small width. The second connection portion 44 is formed on the insulating film 50 formed on the first connection portion 34. In other words, an insulating film 50 having substantially the same shape as that of the first connecting portion 34 is formed on the first connecting portion 34 having a narrow strip shape, and a second connecting portion having a narrower width than the insulating film 50 is formed on the insulating film 50. 44. In the second transparent conductive pattern 40, the second sensing portion 42 and the second connecting portion 44 are formed independently. Furthermore, transparency is required for the insulating film 50. Therefore, as the material of the insulating film 50, SiO ₂ , SiO x , SiN x , and SiO x N y (wherein X and Y are each an arbitrary integer) can be considered as the inorganic material, and as the organic material, an acrylic resin or the like can be considered.

The first transparent conductive pattern 30 and the second transparent conductive pattern 40 are arranged such that the first sensing unit 32 and the second sensing unit 42 do not overlap each other in a plan view. On the other hand, the first connecting portion 34 and the second connecting portion 44 are arranged to intersect each other in plan view. However, the first connection portion 34 and the second connection portion 44 are electrically separated by the insulating film 50.

By arranging the first transparent conductive pattern 30 and the second transparent conductive pattern 40 as described above, a so-called regularly arranged diamond pattern is formed. Each of the first transparent conductive pattern 30 and the second transparent conductive pattern 40 includes a transparent conductive film containing a conductive fiber and a binder.

The structure of the conductive fiber is not particularly limited and may be appropriately selected depending on the purpose, but is preferably any of a solid structure and a hollow structure. Here, a fiber having a solid structure may be referred to as a wire, and a fiber having a hollow structure may be referred to as a tube.

Conductive fibers with an average minor axis length of 5 nm to 1,000 nm and an average major axis length of 1 μm to 100 μm are sometimes referred to as "nano wires".

In addition, the average short-axis length is 1 nm to 1,000 nm, and the average long-axis length is 0.1 μm to 1,000 μm, and the conductive fiber having a hollow structure is called a "nanotube".

The material of the conductive fiber is not particularly limited as long as it has conductivity, and may be appropriately selected according to the purpose, but is preferably at least one of a metal and carbon. Among these, the conductive fiber is preferably at least one of a metal nanowire, a metal nanotube, and a carbon nanotube.

From the viewpoint of transparency and haze, the average minor axis length is preferably 50 nm or less.

The binder may be appropriately selected from the group consisting of an alkali-soluble resin which is an organic high molecular polymer and which has at least one promoting base in a molecule (preferably a molecule having an acrylic copolymer as a main chain). A soluble group (e.g., a carboxyl group, a phosphoric group, a sulfonic acid group, etc.).

As a material of the transparent substrate 20, for example, a transparent glass substrate such as an alkali-free glass or a soda glass, or a polyethylene terephthalate (PET) or a polyethylene naphthalate (PEN) can be used. ), a transparent synthetic resin substrate such as polyether sulfone (PES), or the like. From the viewpoint of transparency and dimensional stability, it is preferred to use alkali-free glass or PET.

The sensor region S is formed on the transparent substrate 20 by the plurality of first transparent conductive patterns 30 and the plurality of second transparent conductive patterns 40. A plurality of first peripheral wirings 60 and a plurality of second peripheral wirings 70 are formed in the outer peripheral region of the sensor region S on the transparent substrate 20. One end of the first peripheral wiring 60 is electrically connected to one end of the first transparent conductive pattern 30. The other end of the first peripheral wiring 60 is electrically connected to an external connection terminal (not shown). The first peripheral wiring 60 includes a wire portion 60a having a small width, and includes a pad portion 60b having a large width with respect to the wire portion 60a at one end, and a pad 60c having a large width with respect to the wire portion 60a at the other end.

One end of the second peripheral wiring 70 is electrically connected to one end of the second transparent conductive pattern 40. The other end of the second peripheral wiring 70 is electrically connected to an external connection terminal (not shown). The second peripheral wiring 70 includes a line portion 70a having a small width, and includes a pad portion 70b having a width larger than that of the line portion 70a at one end, and a pad 70c having a width larger than the line portion 70a at the other end.

The first peripheral wiring 60 and the second peripheral wiring 70 are formed of a metal film. The metal film contains, for example, a material such as Al, Ag, Cu, Mo, Ti, Cr, or the like. The metal film may also comprise a laminate film of a plurality of materials. For example, it may also be composed of Mo (or Mo alloy) / Al (or Al alloy) / Mo (or A laminated film of Mo alloy).

One end of the first transparent conductive pattern 30 includes a connection portion 36 having a large width electrically connected to the pad portion 60b. The connection portion 36 is electrically connected to the pad portion 60b via a U-shaped insulating film 38.

One end of the second transparent conductive pattern 40 includes a connection portion 46 having a large width electrically connected to the pad portion 70b. The connection portion 46 is electrically connected to the pad portion 70b via the U-shaped insulating film 48.

Fig. 2A is an enlarged plan view showing the pad portion 60b (70b) and the insulating film 38 (48) in the contact region. Fig. 2B is a cross-sectional view taken along line A-A. A line portion 60a (70a) having a small width is formed on a transparent substrate (not shown), and a pad portion 60b (70b) having a large width with respect to the line portion 60a (70a) is formed at one end of the line portion 60a (70a). On the pad portion 60b (70b), a U-shaped insulating film 38 (48) having an opening for exposing a part of the pad portion 60b (70b) is formed. In the present embodiment, the contact hole for connecting the upper and lower wirings is formed of a U-shaped insulating film 38 (48) which is open on the lower side in plan view. On the other hand, a normal contact hole is formed of an insulating film that surrounds the entire periphery in a plan view. In the present embodiment, the shape of the insulating film is different from the previous one.

The U-shaped insulating film 38 (48) has a predetermined opening length L (distance between the opposing insulating films 38). The U-shaped insulating film 38 (48) has a predetermined film thickness t1.

Fig. 3A is an enlarged plan view showing the pad portion 60b (70b), the insulating film 38 (48), and the connecting portion 36 (46) in the contact region. Fig. 3B is a cross-sectional view taken along line B-B of Fig. 3A. The connecting portion is formed so as to cover all of the pad portion 60b (70b) exposed from the opening of the U-shaped insulating film 38 (48). 36 (48).

As shown in FIG. 3B, the U-shaped insulating film 38 (48) is opened on one side, so that the connecting portion 36 (46) and the pad portion 60b (70b) are reliably electrically connected (contacted).

According to the connection structure of the present embodiment, even when the transparent conductive film (the connection portion 36 and the connection portion 46) is formed by transfer, since the insulating film 38 (48) has a U-shaped shape that is open on one side, The transparent conductive film (the connection portion 36 and the connection portion 46) can be surely electrically connected (contacted) to the peripheral wiring (the pad portion 60b and the pad portion 70b).

In addition, the transparent conductive film (the connection portion 36 and the connection portion 46) is formed so as to cover the entire exposed portions of the peripheral wiring (the pad portion 60b and the pad portion 70b). As a result, corrosion of the peripheral wiring can be prevented.

Further, the ratio of the film thickness t1 of the insulating film 38 (48) to the opening length L of the insulating film 38 (48) (the opening length L of the insulating film / the thickness t1 of the insulating film) must be 25 or more. With this range, the transparent conductive film containing the conductive fiber and the binder is not electrically disconnected, and can be reliably electrically connected (contacted) to the peripheral wiring.

The insulating film thickness t1 is preferably 0.2 μm or more and 3.0 μm or less, and the opening length L is preferably 50 μm or more.

Further, when the film thickness of the connecting portion 36 (46) is t2, the ratio of the film thickness t2 of the connecting portion 36 (46) to the thickness t1 of the insulating film 38 (48) (thickness t1/connection portion of the insulating film) The film thickness t2) is preferably 5 or more and 20 or less. With this range, the insulation other than the connection portion is good, and the transparent conductive film containing the conductive fiber and the binder is not electrically disconnected, and can be reliably electrically connected (contacted) to the peripheral wiring.

<Transparent Conductive Film>

The transparent conductive film contains at least a binder and a conductive fiber. The binder is not particularly limited, but preferably contains a photosensitive compound and further contains other components as necessary.

[conductive fiber]

The material of the conductive fiber is not particularly limited as long as it has conductivity, and may be appropriately selected according to the purpose, but is preferably at least one of a metal and carbon. Among these, the conductive fiber is preferably At least one of a metal nanowire, a metal nanotube, and a carbon nanotube.

<<Metal nanowire>> -material-

The material of the above metal nanowire is not particularly limited and may be appropriately selected depending on the purpose.

-metal-

Examples of the metal include copper, silver, gold, platinum, palladium, nickel, tin, cobalt, rhodium, ruthenium, iron, osmium, iridium, manganese, molybdenum, tungsten, rhenium, tantalum, titanium, and rhodium. , bismuth, lead, or alloys of these. Among these, silver and an alloy with silver are preferable from the viewpoint of excellent electrical conductivity.

Examples of the metal used in the alloy with silver include gold, platinum, rhodium, palladium, rhodium, and the like. These may be used alone or in combination of two or more.

-shape-

The shape of the above metal nanowire is not particularly limited. It can be selected according to the purpose, for example, it can be cylindrical, rectangular, or profiled. Any shape such as a columnar shape of a polygon. In applications requiring high transparency, a cross-sectional shape in which a corner of a columnar or cross-sectional polygon is rounded is preferable.

The cross-sectional shape of the above-mentioned metal nanowire can be investigated by applying a metal nanowire aqueous dispersion onto a substrate, and then observing the cross section by a transmission electron microscope (TEM).

- average short axis length and average long axis length -

The average minor axis length (sometimes referred to as "average short axis diameter" and "average diameter") of the above-mentioned metal nanowire is preferably 1 nm to 50 nm, more preferably 10 nm to 40 nm, and thus more preferably It is from 15 nm to 35 nm.

When the average minor axis length is less than 1 nm, the oxidation resistance is deteriorated and the durability is deteriorated. When the thickness exceeds 50 nm, scattering due to the metal nanowire occurs, and sufficient transparency cannot be obtained. Happening.

The average short-axis length of the above-mentioned metal nanowire was observed by a transmission electron microscope (TEM; manufactured by JEOL Ltd., JEM-2000FX), and 300 metal nanowires were observed, and the metal naphthalene was obtained based on the average value thereof. The average short axis length of the rice noodle. Further, the short axis length when the short axis of the metal nanowire is not circular is the shortest length.

The average major axis length (sometimes referred to as "average length") of the above metal nanowire is preferably 1 μm to 50 μm, more preferably 5 μm to 45 μm, still more preferably 10 μm to 40 μm.

If the average long axis length is less than 1 μm, it is difficult to form a tight network, and sufficient conductivity cannot be obtained. If it exceeds 50 μm, the metal nanowire is too long and is manufactured. Wounds and the formation of aggregates during the manufacturing process.

The average major axis length of the above-mentioned metal nanowire is observed by, for example, a transmission electron microscope (TEM; manufactured by JEOL Ltd., JEM-2000FX), and 300 metal nanowires are observed, and the metal is obtained based on the average value thereof. The average long axis length of the nanowire. Further, when the metal nanowire is bent, a value calculated from the radius and the curvature is taken as a long axis length in consideration of a circle in which the metal nanowire is an arc.

-Production method-

The method for producing the above-mentioned metal nanowire is not particularly limited, and it can be produced by any method. However, it is preferred to heat the metal ion while heating in a solvent in which a halogen compound and a dispersion additive are dissolved. Restore to make.

In addition, as a method of manufacturing a metal nanowire, Japanese Patent Laid-Open Publication No. 2009-215594, Japanese Patent Laid-Open No. 2009-242880, Japanese Patent Laid-Open No. 2009-299162, and Japanese Patent Laid-Open No. 2010-84173 The method described in Japanese Laid-Open Patent Publication No. 2010-86714, and the like.

<<Metal nanotube tube>> -material-

The material of the metal nanotube is not particularly limited, and may be any metal, for example, a material of the above-described metal nanowire.

-shape-

The shape of the metal nanotube may be a single layer or a plurality of layers. However, from the viewpoint of excellent conductivity and thermal conductivity, a single layer is preferred.

- average short axis length, average long axis length, thickness -

As the thickness (the difference between the outer diameter and the inner diameter) of the above metal nanotube, it is preferably It is 3 nm to 80 nm, more preferably 3 nm to 30 nm.

When the thickness is less than 3 nm, the oxidation resistance is deteriorated and the durability is deteriorated. When the thickness exceeds 80 nm, scattering due to the metal nanotube may occur.

The average long axis length of the above metal nanotube is preferably from 1 μm to 40 μm, more preferably from 3 μm to 35 μm, and even more preferably from 5 μm to 30 μm.

<<Carbon nanotubes>>

The carbon nanotube (CNT) is a coaxial tubular material in which a graphite-like carbon atom surface (graphene sheet) becomes a single layer or a plurality of layers. The above-mentioned single-layer carbon nanotube tube is called a Single-Wall Nanotube (SWNT), and the above-mentioned multi-layer carbon nanotube tube is called a Multi-Wall Nanotube (MWNT), especially The 2-layer carbon nanotube tube is also called Double-Wall Nanotube (DWNT). In the conductive fiber used in the present invention, the carbon nanotubes may be a single layer or a plurality of layers, but from the viewpoint of excellent conductivity and thermal conductivity, a single layer is preferred.

- aspect ratio -

The aspect ratio of the conductive fiber is preferably 10 or more. The above aspect ratio generally means a ratio of a long side to a short side of a fibrous substance (ratio of an average major axis length to an average minor axis length).

The method for measuring the aspect ratio is not particularly limited, and may be appropriately selected depending on the purpose, and examples thereof include a method of measuring by an electron microscope or the like.

When the aspect ratio of the conductive fiber is measured by an electron microscope, the conductivity can be confirmed by one field of view of an electron microscope. Whether the aspect ratio of the fiber is 10 or more. Further, by measuring the major axis length and the minor axis length of the above-mentioned conductive fibers, the aspect ratio of the entire conductive fiber can be estimated.

Further, when the conductive fiber has a tubular shape, the outer diameter of the tube is used as a diameter for calculating the aspect ratio.

The aspect ratio of the conductive fiber is not particularly limited as long as it is 10 or more, and may be appropriately selected depending on the purpose, but is preferably 50 to 1,000,000, more preferably 100 to 1,000,000.

When the aspect ratio is less than 10, the conductive fibers are not formed into a network, and the conductivity cannot be sufficiently obtained. When the ratio is more than 1,000,000, the conductive fibers may be formed at or after the formation of the conductive fibers. In the treatment, since the conductive fibers are entangled and aggregated before film formation, a stable liquid cannot be obtained.

- ratio of conductive fibers having an aspect ratio of 10 or more -

The ratio of the conductive fibers having an aspect ratio of 10 or more is preferably 50% or more, more preferably 60% or more, and particularly preferably 75% or more in terms of volume ratio of all the conductive compositions. Hereinafter, the ratio of these conductive fibers may be referred to as "the ratio of conductive fibers".

When the ratio of the above-mentioned conductive fibers is less than 50%, the conductive material contributing to conductivity is reduced to cause a decrease in conductivity, and since a close network cannot be formed, voltage concentration and durability are generated. The situation of decline. Further, particles having a shape other than the conductive fibers are not preferable because they do not contribute much to the conductivity and have absorption. Especially in the case of a metal, when the plasmon absorption of a sphere or the like is strong, there is a case where the transparency is deteriorated.

Here, regarding the ratio of the above-mentioned conductive fibers, for example, when the conductive fibers are silver nanowires, the ratio of the conductive fibers can be obtained by filtering the silver nanowire aqueous dispersion to silver The nanowire was separated from the other particles, and the amount of silver remaining on the filter paper and the amount of silver permeating through the filter paper were measured using an Inductively Coupled Plasma (ICP) luminescence analyzer. The conductive fibers remaining on the filter paper were observed by TEM, and the short axis lengths of 300 conductive fibers were observed, and the distribution thereof was examined, thereby confirming that the short axis length was 200 nm or less and the long axis length was 1 Conductive fibers of more than μm. In addition, it is preferable that the filter paper is measured for the longest axis of particles other than the conductive fibers having a short axis length of 200 nm or less and a long axis length of 1 μm or more in the TEM image, and the length is the longest axis. It is a filter paper which is twice or more and is the shortest length of the long axis of the conductive fiber.

Here, the average minor axis length and the average major axis length of the conductive fiber can be obtained by observing a TEM image or an optical microscope image, for example, using a transmission electron microscope (TEM) and an optical microscope. In the meantime, the average minor axis length and the average major axis length of the conductive fibers were observed by a transmission electron microscope (TEM), and were determined based on the average value of 300 conductive fibers.

In the following, the conductive layer further containing a conductive fiber and a binder (photosensitive resin) is described, but the photosensitive layer (patterning material) containing the photosensitive resin may not necessarily be integrated with the conductive layer containing the conductive fiber. Patterning is performed by laminating a conductive layer and a photosensitive layer (patterned layer), or transferring a conductive layer onto a transfer target, and then transferring a photosensitive layer (patterned layer) or a screen printing resist material Use a mask.

<<Binder>>

The binder may be appropriately selected from the group consisting of an alkali-soluble resin which is an organic polymer and which has at least one promotion in a molecule (preferably a molecule having an acrylic copolymer as a main chain). An alkali soluble group (e.g., a carboxyl group, a phosphate group, a sulfonic acid group, etc.).

Among these, an alkali-soluble resin which is soluble in an organic solvent and which can be developed by a weakly basic aqueous solution is preferable, and it is particularly preferable to have an acid-dissociable group and to act on an acid-dissociable group by an acid. When dissociated, it becomes an alkali-soluble alkali-soluble resin.

Here, the above acid dissociable group means a functional group which can be dissociated in the presence of an acid.

For the production of the above binder, for example, a method using a known radical polymerization method can be applied. The polymerization conditions such as the temperature, the pressure, the type and amount of the radical initiator, and the type of the solvent when the alkali-soluble resin is produced by the above-described radical polymerization method can be easily set by a person skilled in the art, and conditions can be experimentally specified.

The organic polymer is preferably a polymer having a carboxylic acid in a side chain (a photosensitive resin having an acidic group).

Examples of the polymer having a carboxylic acid in the side chain include, for example, JP-A-59-44615, JP-A-54-34327, JP-A-58-12577, and JP-A-54- Methacrylic acid copolymer, acrylic acid copolymer, itaconic acid copolymer, and croton described in each of the publications of Japanese Laid-Open Patent Publication No. Sho 59-53836 Crotonic acid copolymer, maleic acid copolymerization a compound, a partially esterified maleic acid copolymer, or the like, an acidic cellulose derivative having a carboxylic acid in a side chain, an acid anhydride added to a polymer having a hydroxyl group, and the like, and further, a side chain A high molecular polymer having a (meth)acryloyl group is preferred as the polymer.

Among them, particularly preferred are benzil (meth)acrylate/(meth)acrylic copolymer, and benzyl (meth)acrylate/(meth)acrylic acid/other monomer. Multicomponent copolymer.

Further, a polymer having a (meth)acryl fluorenyl group in a side chain or a (meth)acrylic acid/glycidyl (meth)acrylate/other monomer may be mentioned. Multicomponent copolymers are useful polymers. The polymer can be used in combination in any amount.

In addition to the above, a 2-hydroxypropyl (meth) acrylate/polystyrene macromonomer/benzyl methacrylate/A group as described in Japanese Laid-Open Patent Publication No. Hei No. 7-14065. Acrylic acid copolymer, 2-hydroxy-3-phenoxypropyl acrylate/polymethyl methacrylate macromonomer/benzyl methacrylate/methacrylic acid copolymer, 2-hydroxyethyl methacrylate/ Polystyrene macromonomer/methyl methacrylate/methacrylic acid copolymer, 2-hydroxyethyl methacrylate/polystyrene macromonomer/benzil methacrylate/methacrylic acid Copolymers, etc.

As a specific structural unit among the above alkali-soluble resins, (meth)acrylic acid and other monomers copolymerizable with the (meth)acrylic acid are suitable.

Examples of the other monomer copolymerizable with (meth)acrylic acid include an alkyl (meth)acrylate, an aryl (meth)acrylate, and a vinyl compound. The hydrogen atoms of the alkyl groups and the aryl groups may also be substituted by a substituent.

Examples of the (meth)acrylic acid alkyl ester or the (meth)acrylic acid aryl ester include methyl (meth)acrylate, ethyl (meth)acrylate, and propyl (meth)acrylate. Butyl acrylate, isobutyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, phenyl (meth)acrylate, (methyl) Benzyl acrylate, toluene (meth)acrylate, naphthyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate And dicyclopentenyloxyethyl (meth)acrylate. These may be used alone or in combination of two or more.

Examples of the vinyl compound include styrene, α-methylstyrene, vinyltoluene, glycidyl methacrylate, acrylonitrile, vinyl acetate, and N-vinylpyrrolidine. N-vinylpyrrolidone, tetrahydrofurfuryl methacrylate, polystyrene macromonomer, polymethyl methacrylate macromonomer, CH ₂ =CR ¹ R ² , CH ₂ =C (R ¹ )(COOR ³ ) [wherein R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, R ² represents an aromatic hydrocarbon ring having 6 to 10 carbon atoms, and R ³ represents a carbon number of 1 to 5; 8 alkyl or carbon 6 to 12 aralkyl] and the like. These may be used alone or in combination of two or more.

The weight average molecular weight of the above binder is preferably from 1,000 to 500,000, more preferably from 3,000 to 300,000, still more preferably from 5,000 to 200,000, from the viewpoints of alkali dissolution rate, film physical properties and the like.

Here, the above weight average molecular weight can be determined by gel permeation chromatography and determined using a standard polystyrene calibration curve.

The content of the above binder is preferably 40 with respect to the entire conductive layer. The mass % to 95% by mass, more preferably 50% by mass to 90% by mass, and still more preferably 70% by mass to 90% by mass. When it is in the range of the above content, the coexistence of developability and conductivity of the metal nanowire can be achieved.

-Photosensitive compound -

The photosensitive compound refers to a compound that imparts a function of forming an image by exposure to a conductive layer or an opportunity to form an image by exposure. Specific examples thereof include (1) a compound which generates an acid by exposure (photoacid generator), (2) a photosensitive quinonediazide compound, (3) a photo radical generator, and the like. These may be used alone or in combination of two or more. Further, in order to adjust the sensitivity, a sensitizer or the like may be used in combination.

--(1) Photoacid generator --

As the photoacid generator (1), a photoinitiator-based photoinitiator, a photoradical polymerization photoinitiator, a dye-based photo-decolorizer, a photochromic agent, or a micro-resistance can be suitably selected. A known compound which generates an acid by irradiation with actinic rays or radiation used in a microresist or the like, and a mixture thereof.

The photoacid generator (1) is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include diazonium, sulfonium salts, sulfonium salts, sulfonium salts, and sulfhydrazine sulfonates. Imidosulfonate, oxime sulfonate, diazo disulfone, diterpene, o-nitrobenzyl sulfonate, and the like. Among these, a sulfimine sulfonate, an oxime sulfonate, and an o-nitrobenzyl sulfonate which are a compound which produces a sulfonic acid are especially preferable.

In addition, regarding a compound which generates an acid by irradiation of actinic rays or radiation, or a compound which is introduced into a main chain or a side chain of a resin, for example, US Pat. No. 3,849,137, German Patent No. 3914407 can be used. The specification, Japanese Patent Laid-Open No. 63-26653, Japanese Patent Laid-Open No. Sho 55-164824, Japanese Patent Laid-Open No. Sho 62-69263, Japanese Patent Laid-Open No. Sho 63-146038, Japanese Patent Laid-Open No. 63-163452 The compound described in each of the publications of Japanese Patent Laid-Open Publication No. SHO-62-153853, No. 63-146029, and the like.

Further, a compound which generates an acid by light as described in each of the specifications of the U.S. Patent No. 3,779,778 and the European Patent No. 126,712 can also be used.

--(2) quinonediazide compound --

The (2) quinonediazide compound can be obtained, for example, by subjecting a 1,2-quinonediazidesulfonium chloride, a hydroxy compound, or an amine compound to a condensation reaction in the presence of a dehydrochlorinating agent.

The (1) photoacid generator and the (2) quinonediazide compound are blended with respect to the binder in view of the difference in the dissolution rate between the exposed portion and the unexposed portion and the allowable range of the sensitivity. The total amount is 100 parts by mass, preferably 1 part by mass to 100 parts by mass, more preferably 3 parts by mass to 80 parts by mass.

Further, the above (1) photoacid generator may be used in combination with the above (2) quinonediazide compound.

In the present invention, among the above (1) photoacid generators, a compound which generates a sulfonic acid is preferred, and from the viewpoint of high sensitivity, an oxime sulfonate compound as described below is particularly preferred.

When the compound having a 1,2-naphthoquinonediazide group is used as the above (2) quinonediazide compound, the sensitivity is high and the developability is good.

Among the above (2) quinonediazide compounds, from the viewpoint of high sensitivity, the following compounds in which D is independently a hydrogen atom or a 1,2-naphthoquinonediazide group are preferred.

[Chemical 2]

--(3) Photoradical generator --

The above photoradical generator has a function of directly absorbing light or generating a decomposition reaction or a hydrogen abstraction reaction by light sensitization, and generating a polymerization active radical. The photoradical generating agent preferably has an absorber in a region having a wavelength of from 300 nm to 500 nm.

These photoradical generators may be used alone or in combination of two or more. The content of the above photoradical generator is relative to that of the transparent conductive film The total solid content of the coating liquid is preferably from 0.1% by mass to 50% by mass, more preferably from 0.5% by mass to 30% by mass, even more preferably from 1% by mass to 20% by mass. Within the above numerical range, good sensitivity and pattern formation properties can be obtained.

The photo-radical generating agent is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include a compound group described in JP-A-2008-268884. Among these, from the viewpoint of exposure sensitivity, triazine-based compounds, acetophenone-based compounds, acylphosphine (oxide) compounds, and hydrazine are particularly preferred. An (oxime)-based compound, an imidazole-based compound, and a benzophenone-based compound.

As the above photoradical generator, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4] is suitable from the viewpoint of exposure sensitivity and transparency. -(4-morpholinyl)phenyl]-1-butanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone- 1, 2-methyl-1-(4-methylthiophenyl)-2-morpholinylpropan-1-one, 2,2'-bis(2-chlorophenyl)-4,4',5 , 5'-tetraphenylbiimidazole, N,N-diethylaminodiphenyl ketone, 1,2-octanedione, 1-[4-(phenylthio)-, 2-(o-benzamide Baseline)].

In order to enhance the exposure sensitivity, a coating liquid for a transparent conductive film may also be used in combination with a photo radical generating agent and a chain transfer agent.

Examples of the chain transfer agent include N,N-dialkylaminobenzoic acid alkyl esters such as N,N-dimethylaminobenzoic acid ethyl ester, 2-mercaptobenzothiazole, and 2-mercaptobenzoene. Oxazole, 2-mercaptobenzimidazole, N-phenylmercaptobenzimidazole, 1,3,5-tris(3-mercaptobutoxyethyl)-1,3,5-triazine -2,4,6(1H,3H,5H)-trione or the like having a heterocyclic fluorenyl compound, pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate) An aliphatic polyfunctional thiol compound such as butyrate) or 1,4-bis(3-mercaptobutoxy)butane. These may be used alone or in combination of two or more.

The content of the chain transfer agent is preferably 0.01% by mass to 15% by mass, more preferably 0.1% by mass to 10% by mass, and still more preferably 0.5% by mass based on the total solid content of the coating liquid for the transparent conductive film. %~5 mass%.

-Other ingredients -

Examples of the other components include various additives such as a crosslinking agent, a dispersant, a solvent, a surfactant, an antioxidant, a vulcanization inhibitor, a metal corrosion inhibitor, a viscosity modifier, and a preservative.

--crosslinker --

The above-mentioned crosslinking agent is a compound which forms a chemical bond by a radical or an acid and heat, and hardens the conductive layer, and examples thereof include, for example, a methylol group, an alkoxymethyl group, and a decyloxymethyl group. At least one base-substituted melamine compound, guanamine compound, acetylaluryl compound, urea (urea) compound, phenolic compound or phenol ether compound, epoxy system a compound, an oxetane compound, a sulfur epoxy compound, an isocyanate compound, or an azide compound; and a compound having an ethylenically unsaturated group such as a methyl methacrylate group or an acryl fluorenyl group; Wait. Among these, an epoxy compound, an oxetane compound, and a compound having an ethylenically unsaturated group are particularly preferable from the viewpoint of film properties, heat resistance, and solvent resistance.

Further, the above oxetane resin may be used singly or in combination with an epoxy resin. In particular, from the viewpoint of high reactivity and improving the physical properties of the film, it is preferably used in combination with an epoxy resin.

The content of the crosslinking agent is preferably from 1 part by mass to 250 parts by mass, more preferably from 3 parts by mass to 200 parts by mass, per 100 parts by mass of the total amount of the binder.

--Dispersant--

The above dispersant is used to prevent aggregation of the above-mentioned conductive fibers and to disperse them. The dispersing agent is not particularly limited as long as it can disperse the above-mentioned conductive fibers, and can be appropriately selected according to the purpose. For example, a commercially available low molecular pigment dispersant or a polymer pigment dispersant can be used, and particularly preferably Examples of the polymer dispersant having properties of adsorbing on the conductive fibers include polyvinylpyrrolidone, BYK series (BYK-Chemie), and Solsperse series (Lubrizol, Japan). Company manufacturing, etc.), Ajisper series (manufactured by Ajinomoto Co., Ltd.), etc.

The content of the dispersant is preferably 0.1 parts by mass to 50 parts by mass, more preferably 0.5 parts by mass to 40 parts by mass, even more preferably 1 part by mass to 30 parts by mass, per 100 parts by mass of the above-mentioned binder.

When the content is less than 0.1 part by mass, the conductive fibers may aggregate in the dispersion, and if it exceeds 50 parts by mass, a stable liquid film may not be formed in the coating step, and uneven coating may occur. .

--Solvent --

The solvent is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate. Ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, ethyl lactate, 3-methoxybutanol, water, 1-methoxy-2-propanol, isopropyl acetate, Methyl lactate, N-methylpyrrolidone (NMP), gamma-butyrolactone (GBL), propylene carbonate, and the like. These may be used alone or in combination of two or more.

--Anti-metal corrosion agent --

The metal corrosion inhibitor is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include mercaptans and azoles.

By containing the above-mentioned metal corrosion inhibitor, a more excellent rust prevention effect can be exhibited.

The metal corrosion inhibitor can be added in a state of being dissolved in a coating liquid for a transparent conductive film, in a state of being dissolved by a suitable solvent, or a powder, or in the production of a transparent conductive material to be described later. After the conductive film of the coating liquid for the film, the conductive film is immersed in the anti-metal corrosion agent bath.

Next, a method of manufacturing a touch panel using a transfer method will be described with reference to FIGS. 4 to 6C.

(conductive layer transfer material)

A conductive layer transfer material is used in the method of manufacturing the touch panel. The conductive layer transfer material has a transfer substrate, and has a buffer layer for enhancing transfer uniformity to the transfer target, and a conductive layer containing a binder and conductive fibers on the transfer substrate. Preferably, the conductive layer transfer material has an adhesive layer on the conductive layer, and may have an antifouling layer, an ultraviolet (UV) cut-off layer, an anti-reflective layer and the like as needed. In addition, in order to prevent damage or performance degradation of the functional layer such as the conductive layer, it is also easy to laminate Adhesive protective film.

The conductive layer transfer material is not particularly limited as long as it has the above-described configuration, and may be appropriately selected depending on the purpose. For example, the shape may be a film or a sheet. The single layer structure, the laminated structure, and the like are listed as the above-mentioned sizes, and can be appropriately selected depending on the use and the like.

The conductive layer transfer material is preferably flexible and transparent, and the transparent layer includes colored transparent, translucent, colored translucent, and the like in addition to colorless transparency.

Here, FIG. 4 is a schematic view showing an example of a conductive layer transfer material. The conductive layer transfer material 6 of FIG. 4 has a transfer substrate 1 and has a buffer layer 2 and a conductive layer 3 on one surface of the substrate.

In addition, FIG. 5 is a schematic view showing another example of the conductive layer transfer material. The conductive layer transfer material 7 of FIG. 5 is the conductive layer transfer material 6 of FIG. 4, and the conductive layer transfer material of the adhesion layer 4 is provided on the conductive layer 3.

Further, although not shown in the drawings, the conductive layer in the conductive layer transfer material may be patterned or unpatterned. The patterning described above is an electrode shape which is carried out in the conventional ITO transparent conductive film. Specifically, a pattern called a stripe shape, a rhombus type disclosed in the WO2005/114369 manual, the WO2004/061808 manual, the Japanese Patent Laid-Open No. 2010-33478, and the Japanese Patent Laid-Open Publication No. 2010-44453 Patterns, etc.

The total thickness A of the conductive layer and the buffer layer and the average thickness B of the transfer substrate satisfy the following formula A/B = 0.01 to 0.7, and preferably A/B = 0.02 to 0.6. If the above A/B is less than 0.01, there is a turn When the transfer uniformity of the printing body is lowered, if it exceeds 0.7, the curl balance may collapse.

The average thickness of the transfer substrate is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 1 μm to 500 μm, more preferably 3 μm to 400 μm, and still more preferably 5 μm to 300 μm.

When the average thickness is less than 1 μm, it may be difficult to handle the conductive layer transfer material. When the thickness exceeds 500 μm, the rigidity of the transfer substrate may increase and the transfer uniformity may be impaired.

The average thickness of the above conductive layer is preferably from 0.01 μm to 2 μm, more preferably from 0.03 μm to 1 μm. When the average thickness is less than 0.01 μm, the in-plane distribution of conductivity may be uneven. When the thickness is more than 2 μm, the transmittance may be lowered and the transparency may be impaired.

The average thickness of the buffer layer is preferably from 1 μm to 50 μm, more preferably from 1 μm to 30 μm, and still more preferably from 5 μm to 20 μm. When the average thickness is less than 1 μm, the transfer uniformity may be impaired, and if it exceeds 50 μm, the curl balance of the transfer material may be lowered.

Here, the average thickness of the transfer substrate, the average thickness of the conductive layer, and the average thickness of the buffer layer can be measured by, for example, cutting a cross section of a material by cutting with a microtome, and performing SEM observation. Alternatively, TEM observation was performed on a section prepared by using a microtome after being embedded in an epoxy resin. The average thickness of each of the above layers was an average value of 10 sites.

<Transfer substrate>

The shape, structure, size, and the like of the transfer substrate are not particularly limited, and may be appropriately selected depending on the purpose. For example, the shape may be a film shape or Sheet and so on. The above structure includes a single layer structure, a laminated structure, and the like. The above size can be appropriately selected depending on the use and the like.

The transfer substrate is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include a transparent glass substrate, a synthetic resin sheet (film), a metal substrate, a ceramic plate, and a semiconductor substrate having a photoelectric conversion element. . If necessary, the substrate may be subjected to a chemical treatment such as a decane coupling agent, a plasma treatment, an ion plating, a sputtering, a gas phase reaction method, or a vacuum deposition.

Examples of the transparent glass substrate include white glass, blue glass, and sapphire glass coated with cerium oxide. Further, it may be a thin glass substrate having a thickness of 10 μm to several hundreds μm which has been developed in recent years.

Examples of the synthetic resin sheet include polyethylene terephthalate (PET) sheet, polycarbonate sheet, Triacetyl Cellulose (TAC) sheet, polyether sheet, and polyester sheet. , acrylic resin sheet, vinyl chloride resin sheet, aromatic polyamide resin sheet, polyamidimide sheet, polyimide sheet, and the like.

Examples of the metal substrate include an aluminum plate, a copper plate, a nickel plate, and a stainless steel plate.

The total visible light transmittance of the transfer substrate is preferably 70% or more, more preferably 85% or more, still more preferably 90% or more. If the total visible light transmittance is less than 70%, the transmittance may be low and it may be a problem in practical use.

Further, in the present invention, as the transfer substrate, a transfer substrate which is colored to such an extent that the object of the present invention is not impaired can be used.

<buffer layer>

The shape, the structure, the size, and the like of the above-mentioned buffer layer are not particularly limited, and may be appropriately selected depending on the purpose. For example, the shape may be a film or a sheet. The above structure includes a single layer structure, a laminated structure, and the like. The above size can be appropriately selected depending on the use and the like.

The buffer layer is a layer that functions to enhance transferability with the transfer target, and contains at least a polymer, and further contains other components as necessary.

-polymer-

The polymer is not particularly limited as long as it is a thermoplastic resin which softens upon heating, and may be appropriately selected according to the purpose, and examples thereof include an acrylic resin, a styrene-acrylic copolymer, polyvinyl alcohol, polyethylene, and ethylene. Vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, polyvinyl chloride, gelatin; nitrocellulose, cellulose triacetate, cellulose diacetate, cellulose acetate butyrate, acrylic acid a cellulose ester such as acid cellulose; a homopolymer comprising vinylidene chloride, vinyl chloride, styrene, acrylonitrile, vinyl acetate, alkyl acrylate (carbon number 1-4), vinyl pyrrolidone or the like Copolymers, soluble polyesters, polycarbonates, soluble polyamines, and the like. These may be used alone or in combination of two or more.

The polymer used in the above buffer layer is preferably a thermoplastic resin which is softened by heating. The glass transition temperature of the buffer layer is preferably from 40 ° C to 150 ° C. If it is lower than 40 ° C, it may be too soft at room temperature to cause poor handleability. If it is higher than 150 ° C, the buffer layer is not softened in the thermal lamination mode, resulting in poor transferability of the conductive layer. Good situation. Further, the glass transition temperature can also be adjusted by adding a plasticizer or the like.

As the other components mentioned above, Japanese Patent Laid-Open No. 5-72724 The organic polymer substance described later in paragraph [0007], various plasticizers, supercooling substances, adhesion improving agents, surfactants, mold release agents, and the like, which are used to adjust the adhesion to the transfer substrate. Thermal polymerization inhibitor, solvent, and the like.

The buffer layer can be formed by applying a coating liquid for a buffer layer containing the above polymer and, if necessary, the other components, to a transfer substrate, and drying the coating layer.

The other components are not particularly limited and may be appropriately selected according to the purpose, and examples thereof include various additives such as a filler, a surfactant, an antioxidant, a vulcanization inhibitor, a metal corrosion inhibitor, a viscosity modifier, and a preservative.

The buffer layer can be formed by applying a coating liquid for a buffer layer containing the above polymer and, if necessary, the other components, to a substrate, followed by drying.

The coating method is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include a roll coating method, a bar coating method, a dip coating method, a spin coating method, a casting method, a die coating method, a knife coating method, and a gravure method. Coating method, curtain coating method, spray coating method, knife coating method, and the like.

Here, FIG. 6A to FIG. 6C are views showing an example of a transfer method using the conductive layer transfer material 6 of the present invention.

Fig. 6A shows a conductive layer transfer material 6 having a transfer substrate 1 and having a buffer layer 2 and a conductive layer 3 on one surface of the transfer substrate. As shown in FIG. 6B, the buffer layer 2 and the conductive layer 3 of the conductive layer transfer material 6 shown in FIG. 6A are bonded to the glass substrate 8 as a transfer target by pressurization and heating using a laminator (corresponding to On the transparent substrate of the touch panel. Then, As shown in FIG. 6C, the transfer substrate 1 is peeled off, whereby the buffer layer 2 and the conductive layer 3 are transferred onto the glass substrate 8.

When the conductive layer 3 on the transfer substrate 1 is transferred onto the glass substrate 8, the glass substrate 8 preferably has a temperature range of 90 ° C or more and 120 ° C or less. By setting it as the range, the conductive layer is not insulated, and the conductive layer 3 can be transferred onto the glass substrate 8. When the substrate temperature is less than 90 ° C, the conductive layer 3 cannot be transferred onto the glass substrate 8. When the temperature exceeds 120 ° C, the conductive fibers are deformed by heat, and the conductive layer 3 is insulated.

Further, when the conductive layer 3 on the transfer substrate 1 is transferred onto the glass substrate 8, the transfer pressure is preferably in the range of 0.4 MPa or more and 0.8 MPa or less. By setting this range, the conductive layer 3 can be transferred onto the glass substrate 8 without disconnection. In the case of a transfer pressure of less than 0.4 MPa, the conductive layer is not transferred to the glass substrate due to insufficient pressure at the time of transfer, and if it exceeds 0.8 MPa, the conductive fiber is crushed by the transfer pressure. And the conductive layer is broken.

Then, after the conductive layer 3 is transferred onto the glass substrate 8, the conductive layer 3 is exposed and developed to form a plurality of first transparent conductive patterns and a plurality of second transparent conductive patterns.

The touch panel can be manufactured through the above steps.

[Example]

Hereinafter, examples of the invention will be described, but the invention is not limited by the examples.

(Synthesis Example 1) <Synthesis of Adhesive (A-1)>

Use of methacrylic acid as a monomer component constituting the copolymer (Mathacrylic acid, MAA) 7.79 g, Benzyl Methacrylate (BzMA) 37.21 g, and using azobisisobutyronitrile (AIBN) 0.5 g as a radical polymerization initiator to make these The polymerization was carried out in 55.00 g of Propylene Glycol Monomethyl Ether Acetate (PGMEA), whereby a PGMEA solution of the binder (A-1) represented by the following formula was obtained (solid content concentration: 45% by mass). Further, the polymerization temperature is adjusted to a temperature of from 60 ° C to 100 ° C.

The weight average molecular weight (Mw) of the binder (A-1) was measured by Gel Permeation Chromatography (GPC), and the weight average molecular weight (Mw) obtained by polystyrene conversion was 30,000. The molecular weight distribution (Mw/Mn) was 2.21.

(Preparation Example 1) - Preparation of silver nanowire aqueous dispersion -

The following addition liquid A, addition liquid G, and addition liquid H were prepared in advance.

[Add Liquid A]

0.51 g of silver nitrate powder was dissolved in 50 mL of pure water. Later, Tim Add 1 N of ammonia until it becomes transparent. Then, pure water was added in such a manner that the total amount became 100 mL.

[Add liquid G]

Addition G was prepared by dissolving 0.5 g of glucose powder in 140 mL of pure water.

[Add liquid H]

Addition liquid H was prepared by dissolving 0.5 g of Hexadecyl Trimethyl Ammonium Bromide (HTAB) powder in 27.5 mL of pure water.

Then, a silver nanowire aqueous dispersion was prepared in the following manner.

410 mL of pure water was placed in a three-necked flask, and while stirring at 20 ° C, 82.5 mL of the addition liquid H and 206 mL of the addition liquid G (first stage) were added using a funnel. Addition liquid A 206 mL was added to the solution at a flow rate of 2.0 mL/min and a stirring speed of 800 rpm (second stage). After 10 minutes, the addition solution H 82.5 mL (third stage) was added. Thereafter, the internal temperature was raised to 75 ° C at 3 ° C / min. Thereafter, the stirring speed was lowered to 200 rpm and heated for 5 hours.

After the obtained aqueous dispersion was cooled, the ultrafiltration module SIP1013 (manufactured by Asahi Kasei Co., Ltd., cut off molecular weight: 6,000), a magnetic pump, and a stainless steel cup were connected by an anthrone tube as an ultrafiltration device.

The obtained aqueous dispersion (aqueous solution) was placed in a stainless steel cup, and the pump was operated to perform ultrafiltration. At a time point when the filtrate from the module became 50 mL, 950 mL of distilled water was added to the stainless steel cup and washed. The above washing was repeated until the conductivity became 50 μS/cm or less, and then concentrated to obtain the silver of Preparation Example 1. Nano line water dispersion.

With respect to the silver nanowires in the obtained silver nanowire aqueous dispersion of Preparation Example 1, the average minor axis length and the average major axis length were measured as follows. The results are shown in Table 1.

<Average short axis length (average diameter) and average major axis length of the silver nanowire>

Using a transmission electron microscope (TEM; manufactured by JEOL Ltd., JEM-2000FX), 300 silver nanowires were observed to determine the average minor axis length and the average major axis length of the silver nanowire.

<coefficient of variation of the minor axis length of the silver nanowire>

Using a transmission electron microscope (TEM; manufactured by JEOL Ltd., JEM-2000FX), the short axis lengths of 300 silver nanowires were observed, and the amount of silver transmitted through the filter paper was measured, and the short axis length was 50. A silver nanowire having a length of not less than nm and a length of 5 μm or more is obtained as a ratio (%) of a silver nanowire having an aspect ratio of 10 or more.

Further, the separation of the silver nanowires at the time of obtaining the ratio of the silver nanowires was carried out using a membrane filter (manufactured by Millipore, FALP 02500, pore size: 1.0 μm).

<conductive layer transfer material of sample No. 101> <<Formation of buffer layer>>

Polyethylene terephthalate having an average thickness of 30 μm as a substrate On the ester (PET) film, a coating liquid for a buffer layer having the following composition was applied and dried to form a buffer layer having an average thickness of 10 μm.

- Composition of coating liquid for buffer layer -

. Methyl methacrylate / 2-ethylhexyl acrylate / benzyl methacrylate / methacrylic acid copolymer (copolymerization ratio (mole ratio) = 55 / 30/10/5, weight average molecular weight = 100,000, Glass transfer temperature (Tg) = 70 ° C) ... 6.0 parts by mass

. Styrene/acrylic acid copolymer (copolymer composition ratio (mole ratio) = 65/35, weight average molecular weight = 10,000, glass transition temperature (Tg) = 100 ° C) ... 14.0 parts by mass

. BPE-500 (manufactured by Shin-Nakamura Chemical Co., Ltd.)...9.0 parts by mass

. Megafac F-780-F (manufactured by Dainippon Ink Chemical Industry Co., Ltd.)...0.5 parts by mass

. Methanol...10.0 parts by mass

. Propylene glycol monomethyl ether acetate...5.0 parts by mass

. Methyl ethyl ketone...55.5 parts by mass

<<Production of conductive layer>> - Preparation of MFG dispersion (Ag-1) of silver nanowire -

To the aqueous dispersion of the silver nanowire of Preparation Example 1, polyvinylpyrrolidone (K-30, manufactured by Wako Pure Chemical Industries, Ltd.) and 1-methoxy-2-propanol (MFG) were added. After centrifugation, the supernatant water was removed by decantation, then MFG was added, and redispersion was repeated, and this operation was repeated 3 times to obtain a silver nanowire MFG dispersion (Ag- 1). The final amount of MFG added is silver. The amount of % is adjusted.

- Preparation of a composition for a negative conductive layer -

0.241 parts by mass of the binder (A-1) of Synthesis Example 1, 0.252 parts by mass of KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.), and 0.2252 parts by mass of IRGACURE 379 (manufactured by Ciba Specialty Chemicals Co., Ltd.) were added. EPOPE-3150 (manufactured by Daicel Chemical Co., Ltd.) as a crosslinking agent, 0.0237 parts by mass, Megafac F781F (manufactured by Dianesei Co., Ltd.), 0.0003 parts by mass, propylene glycol monomethyl ether acetate ( PGMEA) 0.9611 parts by mass, and 44.3 parts by mass of 1-methoxy-2-propanol (MFG), and 18.0 parts by mass of the MFG dispersion (Ag-1) of the above-mentioned silver nanowire, and stirred, thereby making a negative A composition for a conductive layer.

- formation of a conductive layer -

The obtained negative conductive layer composition was applied onto a film on which the above buffer layer was formed, and dried to form a conductive layer having an average thickness of 0.1 μm. By the above manner, the conductive layer transfer material of Sample No. 101 was produced.

<Formation of Transparent Conductive Film>

A transparent conductive film was formed by the following method.

[transferd body]

A plurality of transfer bodies are prepared on a glass substrate having a thickness of 0.7 mm, and the transfer target includes a metal layer and an insulating film having a shape different from an opening for exposing a part of the metal layer.

[transfer]

The conductive layer and the buffer layer of the above-mentioned conductive layer transfer material were transferred onto a transfer target (a glass substrate having a thickness of 0.7 mm). Furthermore, the buffer layer is It is removed by spray development.

[exposure]

On the self-mask, exposure was carried out using a high-pressure mercury lamp i-ray (365 nm) at 40 mJ/cm ² (illuminance of 20 mW/cm ² ). Further, since the conductive film contains the negative conductive layer composition, the transparent conductive film is formed on the portion irradiated with the i-ray.

[development]

The exposed substrate was spray-developed for 30 seconds (spray pressure: 0.04 MPa) using a developing solution obtained by dissolving 5 g of sodium hydrogencarbonate and 2.5 g of sodium carbonate in 5,000 g of pure water. Then, the shower is performed by spraying with pure water.

[connection structure]

7A to 7C respectively show a connection structure 1 to a connection structure 3 including a metal layer 100 (corresponding to a peripheral wiring), an insulating film 102, and a transparent conductive film 104 (corresponding to a transparent conductive pattern) containing silver nanowires. In the connection structure 1 to the connection structure 3, the insulating film 102 has a U shape that is opened in one direction, and the transparent conductive film 104 covers the entire exposed portions of the metal layer 100. In the connection structure 1 shown in FIG. 7A, the opening direction of the insulating film 102 is the same direction as the extending direction of the transparent conductive film 104. In the connection structure 2 shown in FIG. 7B, the opening direction of the insulating film 102 is a direction opposite to the extending direction of the transparent conductive film 104. In the connection structure 3 shown in FIG. 7C, the opening direction of the insulating film 102 is a direction orthogonal to the extending direction of the transparent conductive film 104.

8A and 8B show a connection structure 4 including a metal layer 100, an insulating film 102, and a transparent conductive film 104, and a connection structure 5, respectively. In the connection structure 4 shown in FIG. 8A, the insulating film 102 is an exposed portion surrounding the metal layer 100. The rectangle has no open part. The transparent conductive film 104 completely covers the exposed portions of the metal layer 100.

In the connection structure 5 shown in FIG. 8B, the opening direction of the insulating film 102 is a direction opposite to the extending direction of the transparent conductive film 104, and the transparent conductive film 104 covers only a part of the exposed portion of the metal layer 100.

[Manufacture conditions]

For the connection structure 1 to the connection structure 5, a plurality of samples (samples having different thicknesses of the insulating film 102, the opening length of the insulating film 102, the temperature of the glass substrate at the time of transfer, the transfer pressure, and the thickness of the transparent conductive film 104 are prepared. 1~sample 21).

[Evaluation]

Regarding Samples 1 to 21, the contact properties of the metal layer 100 with the transparent conductive film 104 and the corrosivity of the metal layer 100 were evaluated. Regarding the contact property, the resistance value between the metal layer 100 and the transparent conductive film 104 was measured by using a tester to evaluate. A resistance value of 1 MΩ or more was judged to be poor contact. Regarding the corrosivity, the sample was immersed in an alkaline developing solution (potassium hydroxide aqueous solution) for 10 minutes, and evaluated with or without corrosion. The production conditions and evaluation results of Samples 1 to 21 are shown in the table shown in Table 2.

Samples 1 to 3 have a U-shape in plan view and have an opening length/film thickness of 25 or more. Therefore, good results have been obtained with respect to contact properties and corrosivity. In the sample 4, since the insulating film 102 has a rectangular shape surrounding the exposed portion and does not have an open portion, good results have not been obtained with respect to contact properties. Since the sample 5 was not covered with the transparent conductive film 104 by a part of the metal layer 100, good results were not obtained with respect to corrosivity.

The connection structure 2 was applied to the samples 6 to 21. Since Sample 8 and Sample 9 had an opening length/film thickness of 25 or less, good results were not obtained with respect to contact properties.

Sample 16 and sample 20 are not transferred with the transparent conductive film 104, so Contact, no good results.

<Modification>

In Fig. 1, a touch panel in which the connection structure of the present invention is applied in both longitudinal and lateral directions is exemplified. However, the configuration of the present invention is not limited to these examples. For example, it is of course also possible to apply the touch panel of the connection structure of the present invention in either of the longitudinal and lateral directions.

1‧‧‧Transfer substrate

2‧‧‧buffer layer

3‧‧‧ Conductive layer

4‧‧ ‧ close layer

6‧‧‧Conductive layer transfer material

7‧‧‧Conductive layer transfer material

8‧‧‧ glass substrate

10‧‧‧Touch panel

20‧‧‧Transparent substrate

30‧‧‧1st transparent conductive pattern

32‧‧‧1st perception department

34‧‧‧1st connection

36‧‧‧Connecting Department

38‧‧‧1st insulating film

40‧‧‧2nd transparent conductive pattern

42‧‧‧2nd perception department

44‧‧‧2nd connection

46‧‧‧Connecting Department

48‧‧‧2nd insulating film

50‧‧‧Insulation film

60‧‧‧1st perimeter wiring

60a, 70a‧‧‧

60b, 70b‧‧‧ pads

60c, 70c‧‧‧ pads

70‧‧‧2nd perimeter wiring

100‧‧‧metal layer

102‧‧‧Insulation film

104‧‧‧Transparent conductive film

L‧‧‧ opening length

S‧‧‧Sensor area

T1, t2‧‧‧ film thickness

1 is a plan view schematically showing a touch panel of the embodiment.

2A is a plan view of a contact region including a peripheral wiring and an insulating film;

Figure 2B is a cross-sectional view taken along line A-A in the plan view shown in Figure 2A.

3A is a plan view of a contact region including a peripheral wiring, an insulating film, and a transparent conductive pattern.

Figure 3B is a cross-sectional view taken along line B-B of the plan view shown in Figure 3A.

4 is a schematic view showing an example of a conductive layer transfer material;

Fig. 5 is a schematic view showing another example of a conductive layer transfer material;

6A is an explanatory view illustrating a transfer method using a conductive layer transfer material (1)

6B is an explanatory view illustrating a transfer method using a conductive layer transfer material (Part 2)

6C is an explanatory view illustrating a transfer method using a conductive layer transfer material (3)

Fig. 7A is a schematic view showing a plurality of connection structures (1)

Fig. 7B is a schematic view showing a plurality of connection structures (2)

Fig. 7C is a schematic view showing a plurality of connection structures (3)

Fig. 8A is a schematic view showing another plurality of connection structures (1)

Fig. 8B is a schematic view showing another plurality of connection structures (2)

10‧‧‧Touch panel

20‧‧‧Transparent substrate

30‧‧‧1st transparent conductive pattern

32‧‧‧1st perception department

34‧‧‧1st connection

36, 46‧‧‧ Connections

38‧‧‧1st insulating film

40‧‧‧2nd transparent conductive pattern

42‧‧‧2nd perception department

44‧‧‧2nd connection

48‧‧‧2nd insulating film

50‧‧‧Insulation film

60‧‧‧1st perimeter wiring

60a, 70a‧‧‧

60b, 70b‧‧‧ pads

60c, 70c‧‧‧ pads

70‧‧‧2nd perimeter wiring

S‧‧‧Sensor area

Claims (10)

A touch panel includes: a transparent substrate; a plurality of first transparent conductive patterns formed on the transparent substrate along a first direction, and comprising a binder and a conductive fiber; and a plurality of second transparent conductive patterns, The transparent substrate is formed in a second direction orthogonal to the first direction, and includes a binder and a conductive fiber. The plurality of first peripheral wires are formed on the transparent substrate, and each of the above The end portions of the transparent conductive pattern are electrically connected to each other, and the plurality of second peripheral wires are formed on the transparent substrate and electrically connected to the end portions of the second transparent conductive patterns; and the first connection structure is connected to the above Each of the first transparent conductive patterns and the first peripheral wirings and the second connection structure are connected to the second transparent conductive patterns and the second peripheral wirings, and the first connection structure includes the first peripheral wirings a U-shaped first insulating film having an opening for exposing a part of the first peripheral wiring, and the first one covering the exposed first peripheral wiring on the first peripheral wiring Ming film thickness of the conductive pattern, and the length of the opening of the first insulating film / the first insulating film is 25 or more. The touch panel according to claim 1, wherein the second connection structure includes the second peripheral wiring, and is formed on the second peripheral wiring and has a portion for exposing the second peripheral wiring a second U-shaped insulating film having an opening and a second transparent conductive pattern covering the exposed second peripheral wiring, and an opening length of the second insulating film and a film thickness of the second insulating film are 25 the above. The touch panel according to claim 1, wherein the film thickness of the first insulating layer and the film thickness of the first transparent conductive pattern are 5 or more and 20 or less. The touch panel according to the second aspect of the invention, wherein the film thickness of the second insulating layer and the film thickness of the second transparent conductive pattern are 5 or more and 20 or less. The touch panel according to any one of claims 1 to 4, wherein the conductive fiber is a silver nanowire. The touch panel according to any one of claims 1 to 4, wherein the first peripheral wiring and the second peripheral wiring are formed of a metal film. The touch panel according to any one of claims 1 to 4, wherein the conductive fiber has a short axis of 50 nm or less. A method of manufacturing a touch panel, comprising: forming a plurality of first peripheral wirings and a plurality of second peripheral wirings on a transparent substrate; and forming, on each of the first peripheral wirings, the first peripheral wiring a U-shaped first insulating film having a partially exposed opening and/or a U-shaped second insulating film having an opening for exposing a part of the second peripheral wiring on each of the second peripheral wirings; Forming a conductive material containing a binder and a conductive fiber on the transfer substrate a layer; the conductive layer on the transfer substrate is transferred onto the transparent substrate, and covers the exposed portion of the first peripheral wiring and/or the second peripheral wiring, and the first peripheral wiring and the first peripheral wiring The second peripheral wiring is electrically connected to the conductive layer; and the conductive layer is patterned to form a plurality of first transparent conductive patterns extending in the first direction and in a second direction orthogonal to the first direction a plurality of second transparent conductive patterns extending. The method of manufacturing a touch panel according to claim 8, wherein when the conductive layer on the transfer substrate is transferred onto the transparent substrate, the transparent substrate is 90° C. or higher and 120° C. The following temperature range. The method of manufacturing a touch panel according to claim 8 or 9, wherein when the conductive layer on the transfer substrate is transferred onto the transparent substrate, the transfer pressure is 0.4 MPa. Above, the range of 0.8 MPa or less.