JP4177326B2 - Transparent conductor - Google Patents

Description

  The present invention relates to a transparent conductor.

  A panel switch such as a touch panel is generally composed of a pair of transparent electrodes facing each other and a spacer sandwiched between the pair of transparent electrodes. In such a panel switch or the like, when one of the transparent electrodes is pressed, the transparent electrode comes into contact with the other transparent electrode and energization occurs, whereby the position of the contact point is detected. As the transparent electrode, a transparent conductor is used. As the transparent conductor, a film formed of a sputtered film as a conductive layer on a substrate, or a film composed of conductive powder and a binder is formed as a conductive layer. There is something.

As transparent conductors in which a conductive layer made of conductive powder and a binder is formed on a substrate, those described in Patent Documents 1 and 2 below are known. In these Patent Documents 1 and 2, a light-transmitting conductive material is described as a transparent conductor, and in this light-transmitting conductive material, a thermoplastic resin, a thermosetting resin, an ultraviolet ray curing is used as a binder in the conductive layer. Resins such as resins, phenoxy resins, mixed resins of phenoxy resins and epoxy resins, or polyvinylidene fluoride are used.
Japanese Patent Laid-Open No. 08-78164 JP 11-273874 A

  However, when the light-transmitting conductive material described in Patent Documents 1 and 2 is used as a transparent conductor for a touch panel or the like, when the surface of the touch panel or the like is pressed, the opposing transparent conductors are in contact with each other. Therefore, friction occurs between the transparent conductors. For this reason, when the touch panel is repeatedly used, the transparent conductor formed on the substrate may be gradually scraped, resulting in a problem that the transparent conductor itself becomes thin, or the shaved transparent conductor may adhere to the transparent conductor again. . When the transparent conductor itself becomes thin or the transparent conductor reattaches in this way, the electrical resistance value of the transparent conductor rises locally. As a result, malfunctions and position information are not displayed on the touch panel. A situation occurs that shifts.

Therefore, the present invention has been made in view of the above circumstances, and even if friction occurs between the transparent conductors, the surface of the transparent conductor is prevented from being scraped, and the electrical resistance value is sufficiently increased locally. An object of the present invention is to provide a transparent conductor for a touch panel and a panel switch using the same.

  In order to prevent the surface of the transparent conductor from being scraped even when the transparent conductor comes into contact and friction occurs between the transparent conductors, the present inventors have made extensive studies to solve the above problems. It has been found that it is effective to make the surface of the transparent conductor slip easily when the transparent conductors are in contact with each other. As a result of further earnest studies, the present inventors have found that the above problems can be solved by the following invention, and have completed the present invention.

That is, the transparent conductor for a touch panel of the present invention includes a base, a conductive layer containing conductive powder and a resin, and a layer containing a fluorine compound, and the layer containing the fluorine compound has a base with respect to the conductive layer. It is provided on the opposite side, and the thickness of the layer containing a fluorine compound is 1 to 50 nm . Here, the transparent conductor in the present invention includes films and plates, and the film-like transparent conductor has a thickness in the range of 50 nm to 1 mm, and the plate-like transparent conductor has a thickness exceeding 1 mm. Say things.

  Since the transparent conductor of the present invention is provided with a layer containing a fluorine compound on the surface of the transparent conductor, even if friction occurs between the transparent conductors, the surface of the transparent conductor is prevented from being scraped. Can do. For this reason, the situation that the shaved transparent conductor reattaches can be prevented, and as a result, the local increase in the electrical resistance value can be sufficiently suppressed. Furthermore, the layer containing the fluorine compound not only prevents the transparent conductor from being scraped by friction between the transparent conductors, but also functions as a protective film that protects against dirt and the like, and the deterioration of the transparent conductor is sufficient. It is suppressed. Furthermore, it is possible to suppress the occurrence of cracks in the transparent conductor, and the life of the transparent conductor can be extended.

In the transparent conductor for a touch panel , the fluorine compound is preferably a linear molecule. When the fluorine compound is a linear molecule, in the transparent conductor for a touch panel of the present invention, the lubricity of the layer containing the fluorine compound can be improved. If the fluorine compound is a linear molecule, due to the steric hindrance of the fluorine atom, the linear CC bond becomes linear, and the intermolecular force between the fluorine compounds is low, The present inventors are thinking.

In the transparent conductor for a touch panel , the fluorine compound preferably has a side chain, and a fluorine atom is bonded to the side chain.

  In this case, the chemical stability of the fluorine compound can be improved, and the lubricity of the layer containing the fluorine compound can be further improved.

In the transparent conductor for a touch panel, the number of carbon atoms in the fluorine compound is preferably 5 or more. In this case, compared with the case where the number of carbon atoms is less than 5, the lubricity of the layer containing a fluorine compound can be further improved, and the surface of the transparent conductor can be more sufficiently prevented from being scraped.

In the transparent conductor for a touch panel , the fluorine compound preferably has an ether bond. In this case, since a fluorine atom is bonded to the fluorine compound, the fluorine compound has a rigid molecular structure due to the steric hindrance of the fluorine atom. However, if the fluorine compound has an ether bond in the molecule, Since the molecules can freely rotate, vibrate, stretch, and the like, the layer containing the fluorine compound using the fluorine compound can be softened. Therefore, the layer containing the fluorine compound of the transparent conductor using this fluorine compound can not only improve the lubricity but also improve the function as a protective film against cracks and the like. Therefore, according to this transparent conductor, the surface is more sufficiently prevented from being scraped, and the life is further improved.

In the transparent conductor for a touch panel , the fluorine compound is preferably chemically bonded to the surface of the conductive layer. Here, chemically bonded means to remove physical adsorption. For example, even if the transparent conductor is immersed in a solvent that dissolves the fluorine compound, the fluorine compound remains on the surface of the conductive layer. This can be confirmed by remaining. In addition, a confirmation means is not limited to this, It can analyze also by the existing analysis method.

  In this case, since the fluorine compound is chemically bonded to the surface of the conductive layer, the wear resistance of the layer containing the fluorine compound can be further improved.

Moreover, in the said transparent conductor for touchscreens, it is more preferable that the conductive layer contains conductive powder and resin, and the conductive powder and resin constitute the surface of the conductive layer.

  In this case, since the fluorine compound can be chemically bonded not only to the conductive powder but also to the resin, the wear resistance of the layer containing the fluorine compound containing them can be further improved.

The touch panel of the present invention includes a pair of transparent conductors facing each other and a spacer provided between the pair of transparent conductors, and at least one of the pair of transparent conductors is the transparent conductor for a touch panel. It is.

  Since the above-described transparent conductor is used for the touch panel, the obtained touch panel is sufficiently suppressed from scraping the surface of the transparent conductor even when friction occurs between the transparent conductors, and has an electric resistance value. Local elevation is sufficiently suppressed.

According to the transparent conductor for a touch panel of the present invention, even if a fluororesin layer is formed on the surface, it can be used as a transparent conductor without significantly increasing the resistance value, and even if friction occurs between the transparent conductors. The surface of the transparent conductor can be sufficiently prevented from being scraped, and the local increase in electrical resistance can be sufficiently suppressed.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

[First Embodiment]
FIG. 1 is a schematic cross-sectional view showing an embodiment of a touch panel 1 using a transparent conductor of the present invention. As shown in FIG. 1, the touch panel of this embodiment is formed of a pair of transparent electrodes 2a and 2b facing each other and a dot spacer 4 sandwiched between the transparent electrodes 2a and 2b.

  Here, the transparent conductors 2a and 2b will be described. Since the transparent conductors 2a and 2b have the same configuration, only the transparent conductor 2a will be described, and the description of the transparent conductor 2b will be omitted.

  FIG. 2 is a schematic cross-sectional view showing the transparent conductor 2a. As shown in FIG. 2, the transparent conductor 2a includes a base 11, a conductive layer 12 containing conductive powder 12a, and a layer 13 containing a fluorine compound containing a fluorine compound, and a layer 13 containing a fluorine compound. Is provided on the side opposite to the base 11 with respect to the conductive layer 12.

  Here, in the touch panel 1, the transparent conductor 2 a of the present embodiment is arranged so that the surface on which friction occurs is the layer 13 containing a fluorine compound. Therefore, even if friction occurs between the transparent conductors 2a, the transparent conductor 2a has the layer 13 containing the fluorine compound on the surface side where the friction occurs, so that the surface of the transparent conductor 2a can be prevented from being scraped. . In addition, the transparent conductor 2a can also prevent reattachment of the shaved transparent conductor 2a, and can suppress fluctuations in the electrical resistance value. Furthermore, the layer 13 containing the fluorine compound not only prevents the transparent conductor 2a from being scraped by friction between the transparent conductors 2a, but also functions as a protective film that protects against dirt and the like. Suppresses deterioration. Furthermore, it is possible to suppress cracks in the transparent conductor 2a.

  The touch panel 1 is pressed from the upper side A of one transparent electrode 2a and is energized by contacting with the other transparent electrode 2b, and its position is detected. Therefore, when the surface of the touch panel 1 is pressed, the transparent conductors facing each other come into contact with each other. However, since the transparent conductor of the present invention has a layer containing a fluorine compound, the transparent conductors are in contact with each other. Even if friction occurs, it is possible to prevent the surface of the transparent conductor from being scraped and to suppress fluctuations in the electrical resistance value.

  Next, the layer 13 containing a fluorine compound, the conductive layer 12, and the base 11 will be described in more detail.

<Layer containing fluorine compound>
The transparent conductor according to the present embodiment has a layer 13 containing a fluorine compound, and the layer 13 containing a fluorine compound contains a fluorine compound.

  Thus, since the layer 13 containing a fluorine compound of this embodiment contains a fluorine compound, even if friction occurs between the transparent conductors 2a, the surface of the transparent conductor can be prevented from being scraped. Along with this, reattachment of the shaved transparent conductor can be prevented, and a transparent conductor that can suppress fluctuations in the electrical resistance value can be obtained.

  The form of the layer 13 containing a fluorine compound is not particularly limited as long as it contains a fluorine compound. Specifically, the layer 13 containing a fluorine compound is preferably in the form of a film, regardless of whether it is a monomolecular layer or a laminate thereof. Among these, a monomolecular layer is more preferable. In this case, resistance as a conductor and lubricity can be achieved at a high level.

  Moreover, although the thickness of the layer 13 containing a fluorine compound changes with the molecular weights and three-dimensional shape of a fluorine compound, generally it is preferable that they are 1 nm-50 nm. When the thickness is less than 1 nm, the lubricity tends to be lower than when the thickness is in the above range. When the thickness exceeds 50 nm, the conductive layer is compared with the case where the thickness is in the above range. No. 12 surface roughness, refractive index, etc. cause glare and the like, and the visibility tends to decrease.

  The fluorine compound is not particularly limited as long as it contains one or more fluorine atoms in the molecule. Specifically, perfluoropolyether and derivatives thereof, fluorinated alcohols such as 2-perfluorodecylethanol, fluorinated acid halides such as perfluorooctanoyl fluoride, fluorinated acids such as perfluorodecanoic acid, Fluorinated acrylates such as 2- (perfluorooctyl) ethyl acrylate, fluorinated methacrylates such as 2- (perfluoro-5-methylhexyl) ethyl methacrylate, perfluoro (2,5,8,11-tetramethyl-3, 6,9,12-tetraoxapentadecanoyl) fluoride, perfluoropolyoxetane and its derivatives, 3-perfluorohexyl-1,2-epoxypropane, di-heptadecatrifluorodecyldisilazane, heptadecatrifluorodecyl Trimethoxysilane, 1H, 1H-F Data decafluoro nonyl amine. These may be used alone or in combination of two or more.

  The fluorine compound is more preferable as it has more fluorine atoms, and more preferably a so-called perfluoro compound in which all hydrogen atoms are substituted with fluorine atoms. In this case, the lubricity of the layer 13 containing the fluorine compound using the fluorine compound is further improved.

  As the fluorine compound, a commercially available fluorine compound may be used, and a monomer having a fluorine atom, a dimer, a trimer, a tetramer, an oligomer (hereinafter referred to as “monomer etc.”) may be polymerized. Moreover, the copolymer of the monomer etc. which do not have a fluorine atom, and the monomer etc. which have a fluorine atom may be sufficient. Examples of the monomer having a fluorine atom include 2- (perfluorooctyl) ethyl acrylate and 2- (perfluoro-5-methylhexyl) ethyl methacrylate.

  Of these, fluorine-containing acrylates are generally more preferred. When the monomer having a fluorine atom is the above compound, the polymerization reactivity is high and the curability is excellent.

  Moreover, the said fluorine compound may use the compound which does not have a fluorine atom, and may substitute a hydrogen atom for a fluorine atom separately. The fluorination reaction of the compound having no fluorine atom can be carried out by a known method using a compound having no fluorine atom and fluorine gas, an electrophilic fluorinating agent, a nucleophilic fluorinating agent, or the like. Further, the surface of the conductive layer 12 may be directly fluorinated using the fluorinating agent or the like.

  Further, as the fluorine compound, a compound having no fluorine atom may be used and chemically bonded to a short molecule compound having a fluorine atom separately. Examples of the short molecule compound include 2,3,4,5,6-pentafluorophenoxyacetyl chloride, 2,3,4,5,6-pentafluorobenzamide and the like.

  The fluorine compound is preferably a linear molecule. When the fluorine compound is a linear molecule, the lubricity of the layer containing the fluorine compound can be improved in the transparent conductor of the present invention.

  Specific examples include linear perfluoropolyether and derivatives thereof, heptadecatrifluorodecyltrimethoxysilane, and the like.

  The fluorine compound preferably has a side chain (hereinafter referred to as “side chain compound”), and a fluorine atom is bonded to the side chain. When the fluorine compound is a side chain compound, the boiling point of the fluorine compound increases, so that the chemical stability of the fluorine compound can be improved. In addition, the fluorine atom is bonded to the side chain, whereby the lubricity of the layer containing the fluorine compound can be improved in the transparent conductor 2a of the present embodiment.

  Specific examples include perfluoropolyoxetane and its derivatives. More specifically, perfluoropolyoxetane alkoxysilanes can be mentioned.

  In the transparent conductor 2a according to this embodiment, the fluorine compound preferably has an ether bond. In this case, as compared with the case where the fluorine compound does not have an ether bond, the ether bond portion can freely rotate, vibrate, stretch, and the like, so the layer 13 containing the fluorine compound using the fluorine compound is softened. be able to. Therefore, the layer containing the fluorine compound of the transparent conductor using this fluorine compound can not only improve the lubricity but also improve the function as a protective film against cracks and the like. Examples of the fluorine compound having an ether bond include linear perfluoropolyether and derivatives thereof, perfluoropolyoxetane and derivatives thereof.

  The fluorine compound preferably has 5 or more carbon atoms in the fluorine compound. When the number of carbon atoms in the fluorine compound is less than 5, the lubricity of the layer containing the fluorine compound containing the fluorine compound is lowered as compared with the case where the number of carbon atoms is 5 or more.

  In this embodiment, it is preferable that the molecular weight of the fluorine compound to be used is 200-20000. When the molecular weight is less than 200, the lubricity tends to be lower than when the molecular weight is in the above range, and when the molecular weight exceeds 20000, the electrical resistance is higher than that when the molecular weight is in the above range. Tend to rise.

  The fluorine compound is preferably chemically bonded to the surface of the conductive layer. In this case, since the fluorine compound is chemically bonded to the surface of the conductive layer, the wear resistance of the layer containing the fluorine compound can be further improved.

  When the fluorine compound is chemically bonded to the conductive powder or the resin as described above, the fluorine compound has a substituent capable of bonding in the molecule. Examples of the bondable substituent include a group containing a polymerizable double bond such as acryloyl group, methacryloyl group, and styrene group that can be bonded by photo radical polymerization or thermal radical polymerization, water, acid, alkali, in the presence of a catalyst, or heat. Epoxy groups, hydroxyl groups, alkoxy groups, ester groups, acyl groups such as acyl halides, halogen groups, silane groups such as alkoxysilane groups, chlorosilane groups, and silazane groups, carboxylic acid groups, amide groups, amine groups, etc. Can be mentioned.

  In addition, since the said electrically conductive powder has a hydroxyl group on the surface so that it may mention later, this functional group and the substituent which can combine the said fluorine compound will react.

  More preferably, the conductive layer contains conductive powder and resin, and the conductive powder and resin constitute the surface. Thus, when the surface of the conductive layer contains conductive powder and resin, the fluorine compound can be chemically bonded not only to the conductive powder but also to the resin. Abrasion can be further improved.

  In addition, the resin in this case is not particularly limited as long as it has a substituent that is chemically bonded in the molecule similarly to the fluorine compound. Moreover, as said resin, what hardened a photocurable compound, a thermosetting compound, etc., ie, the thing which has a crosslinked structure, is preferable. In this case, since not only the fluorine compound but also adjacent resins are cross-linked, it is possible to suppress moisture from entering the obtained transparent conductor and cracking. The photocurable compound may be any organic compound that is cured by light, and the thermosetting compound may be any organic compound that is cured by heat. Here, the organic compound includes a material that is a raw material of the resin, and specifically includes a monomer that can form the resin. Among the above resins, a photocurable compound is preferable. When the curable compound is a photocurable compound, the curing reaction can be controlled, and the curing can be performed in a short time.

  As said photocurable compound, the monomer etc. which contain a vinyl group, an epoxy group, or those derivatives can be used preferably. These may be used alone or in a mixture of two or more.

<Conductive layer>
The conductive layer 12 contains the conductive powder 12a as described above. The conductive powder 12a is filled so that adjacent conductive powders 12a are in contact with each other. As a result, the function as a conductor is exhibited.

  The conductive powder 12a is made of a transparent conductive oxide material. The transparent conductive oxide material is not particularly limited as long as it has transparency and conductivity. Examples of the transparent conductive oxide material include indium oxide or indium oxide, tin, zinc, tellurium, silver, One doped with at least one element selected from the group consisting of gallium, zirconium, hafnium or magnesium, tin oxide, or tin oxide with at least one selected from the group consisting of antimony, zinc or fluorine Examples include those doped with elements, zinc oxide, or zinc oxide doped with at least one element selected from the group consisting of aluminum, gallium, indium, boron, fluorine, and manganese.

  The average particle size of the conductive powder 12a is preferably 10 nm to 80 nm. When the average particle size is less than 10 nm, the conductivity of the transparent conductor 2a tends to fluctuate more easily than when the average particle size is 10 nm or more. That is, the transparent conductor 2a according to the present embodiment exhibits conductivity due to oxygen defects generated in the conductive powder 12a. However, when the particle size of the conductive powder 12a is less than 10 nm, the particle size is in the above range. In comparison, for example, when the external oxygen concentration is high, oxygen vacancies are reduced and the conductivity may vary. On the other hand, when the average particle size exceeds 80 nm, compared to the case where the particle size is in the above range, for example, in the wavelength region of visible light, light scattering becomes larger than when the average particle size is 80 nm or less, In the visible wavelength region, the transmittance of the transparent conductor 2a tends to decrease and the haze value tends to increase.

  Furthermore, the filling rate of the conductive powder 12a in the transparent conductor 2a is preferably 10% by volume to 70% by volume. When the filling rate is less than 10% by volume, the electrical resistance value of the transparent conductor 2a tends to be higher than when the filling rate is in the above range, and when the filling degree exceeds 70% by volume, Compared with the case where the filling rate is in the above range, the mechanical strength of the film forming the conductive layer 12 tends to decrease.

  Thus, the transparency of a transparent conductor improves more and the initial electrical resistance value can be reduced as the average particle diameter and filling rate of the conductive powder 12a are in the above ranges.

Also it is preferable that the specific surface area of the conductive powder 12a is ^{10m 2} / ^g~50m 2 / g. When the specific surface area is less than 10 m ² / g, the light scattering of visible light tends to increase compared to the case where the specific surface area is in the above range, and when the specific surface area exceeds 50 m ² / g, the specific surface area. Compared with the case where is in the above range, the stability of the transparent conductor 2a tends to be low. In addition, the specific surface area said here shall say the value measured after vacuum-drying a sample for 30 minutes at 300 degreeC using the specific surface area measuring apparatus (model | form: NOVA2000, the product made from Cantachrome).

  In addition, the conductive layer 12 may further contain an additive as necessary. Examples of the additive include a flame retardant, an ultraviolet absorber, a colorant, and a plasticizer.

<Substrate>
The substrate 11 is not particularly limited as long as it is made of a material transparent to high energy rays and visible light described later. That is, the substrate 11 may be a known transparent film, for example, a polyester film such as polyethylene terephthalate (PET), a polyolefin film such as polyethylene or polypropylene, a polycarbonate film, an acrylic film, a norbornene film (manufactured by JSR Corporation, Arton, etc.), etc. Is mentioned. In addition to the resin film, glass can also be used as the substrate 11. Moreover, it is preferable that the said base | substrate 11 consists only of resin. In this case, the transparent conductor is excellent in transparency and flexibility as compared with the case where the substrate 11 includes a resin and a material other than the resin. Therefore, it is particularly effective when used for a touch panel, for example.

<Manufacturing method>
Next, the manufacturing method of the transparent conductor 2a according to the present embodiment will be described in the case where the conductive powder 12a described above is obtained by doping indium oxide with tin (hereinafter referred to as “ITO”).

  First, the conductive powder 12a is placed on a glass substrate (not shown), and a conductive layer containing the conductive powder 12a and a resin is formed. Here, the conductive powder 12a will be described.

  First, indium chloride and tin chloride are coprecipitated by neutralization using an alkali (precipitation step). At this time, the by-product salt is removed by decantation or centrifugation. The obtained coprecipitate is dried, and the obtained dried product is subjected to atmosphere firing and pulverization. Thus, the conductive powder 12a is manufactured. The firing treatment is preferably performed in a nitrogen atmosphere or a rare gas atmosphere such as helium, argon, or xenon from the viewpoint of controlling oxygen defects.

  The conductive powder 12a thus obtained and a photocurable compound as a compound forming a resin are mixed and dispersed in a liquid to obtain a dispersion. Examples of the liquid in which the conductive powder 12a and the photocurable compound are dispersed include saturated hydrocarbons such as hexane, aromatic hydrocarbons such as toluene and xylene, alcohols such as methanol, ethanol, propanol, and butanol, acetone, methyl ethyl ketone, Ketones such as isobutyl methyl ketone and diisobutyl ketone, esters such as ethyl acetate and butyl acetate, ethers such as tetrahydrofuran, dioxane and diethyl ether, N, N-dimethylacetamide, N, N-dimethylformamide, N-methylpyrrolidone And amides. At this time, the photocurable compound may be used by dissolving in the liquid.

  The conductive layer 12 is formed by applying the dispersion thus obtained onto the glass substrate. In addition, when using the said liquid, it is preferable to give a drying process after application | coating. Examples of the coating method include a reverse roll method, a direct roll method, a blade method, a knife method, an extrusion method, a nozzle method, a curtain method, a gravure roll method, a bar coat method, a dip method, a kiss coat method, and a spin coat method. It can apply | coat by methods, such as a squeeze method and a spray.

  Next, the substrate 11 is bonded onto the conductive layer 12. The base 11 can be provided with an anchor layer in advance on the adhesive surface with the conductive layer 12. If an anchor layer is provided in advance on the substrate 11, the conductive layer 12 can be more firmly fixed on the substrate 11 via the anchor layer. As the anchor layer, polyurethane or the like is preferably used.

  Then, the photocurable compound is cured by irradiating the substrate 11 provided on the conductive layer with high energy rays. In addition, the high energy ray mentioned above may be an electron beam, a gamma ray, an X-ray other than an ultraviolet-ray, for example.

  Next, the conductive layer 12 and the substrate 11 are peeled from the glass substrate, and a layer 13 containing a fluorine compound is formed on the peeled surface (conductive layer surface). And the layer 13 containing a fluorine compound is formed by apply | coating a fluorine compound on the conductive layer 12. FIG. At this time, the fluorine compound may be dissolved in a solvent. In this case, it is preferable to perform a drying step after coating. Examples of the fluorine compound coating method include reverse roll method, direct roll method, blade method, knife method, extrusion method, nozzle method, curtain method, gravure roll method, bar coating method, dip method, kiss coating method, Methods such as a spin coating method, a squeeze method, and a spray method can be used. And the transparent conductor 2a shown in FIG. 1 is obtained by the above method.

[Second Embodiment]
Next, a second embodiment of the touch panel of the present invention will be described. In addition, the same code | symbol is attached | subjected to the component same or equivalent to 1st Embodiment, and the overlapping description is abbreviate | omitted.

  FIG. 3 is a schematic cross-sectional view showing a transparent conductor used in the second embodiment of the touch panel of the present invention. As shown in FIG. 3, the transparent conductor 20 includes a substrate 11, a curable resin layer 15, a conductive layer 12 containing conductive powder 12 a, and a layer 13 containing a fluorine compound. The curable resin layer 15, the conductive layer 12, and the layer 13 containing a fluorine compound are sequentially laminated. The conductive layer 12 is filled with the conductive powder 12a, and the penetrated curable resin 15a exists between the conductive powder 12a, and the curable resin 15a fixes the conductive powder 12a.

  According to the touch panel having the transparent conductor 20, even if the touch panel is repeatedly used, the surface of the transparent conductor can be sufficiently prevented from being scraped. For this reason, it can fully prevent that the shaved transparent conductor reattaches to the opposing transparent conductor, and can also suppress the local raise of an electrical resistance value fully. Therefore, according to the touch panel of the present embodiment, it is possible to sufficiently prevent a situation in which malfunction or position information is shifted even if it is repeatedly used.

  The transparent conductor 20 can be manufactured as follows, for example. First, the conductive powder 12a is placed on a glass substrate (not shown). At this time, it is preferable that an anchor layer for fixing the conductive powder 12a on the substrate is provided in advance on the substrate. If the anchor layer is provided in advance, the conductive powder 11 can be firmly fixed on the substrate, and the conductive powder 12a can be easily placed. As said anchor layer, a polyurethane etc. are used suitably, for example.

  In order to fix the conductive powder 12a on the substrate, the conductive powder 12a may be compressed toward the glass substrate to form a compressed layer. In this case, the conductive powder 12a can be adhered to the glass substrate without forming an anchor layer, which is useful. This compression can be performed by a sheet press, a roll press or the like. In this case as well, it is preferable to previously provide an anchor layer on the substrate. In this case, the conductive powder 12a can be more firmly fixed.

  Examples of the substrate include glass, films of polyester, polyethylene, polypropylene, and various plastic substrates.

  Next, the curable resin 15a is applied on one surface of the compression layer. In this way, a part of the curable resin 15a penetrates into the compression layer. The curable resin 15a used at this time is not particularly limited, but as the curable resin 15a, one that can be cured by high energy rays as described above is used. The same resin as described above may be used.

  Then, the substrate 11 is provided on the curable resin 15a and irradiated with energy rays, whereby the conductive layer 12, the curable resin layer 15, and the substrate 11 are formed. As a result, the curable resin 15a, which has penetrated into the conductive powder 12a and has been cured, adheres the conductive powder 12a to form the conductive layer 12. Further, the curable resin 15a that does not penetrate into the conductive powder 12a is cured as it is to form the curable resin layer 15. At this time, the substrate 11 and the curable resin layer 15 are further bonded. In addition, the above-mentioned high energy rays may be light such as ultraviolet rays, and may be electron beams, γ rays, X rays, and the like.

  Next, the substrate is peeled from the obtained laminate, and a fluorine compound is applied to the surface of the conductive layer 12 as in the first embodiment, thereby forming a layer containing a fluorine compound. Thus, the transparent conductor 20 shown in FIG. 2 is obtained.

  It is preferable that the content rate of the electroconductive powder 12a in the material which comprises the electroconductive layer 12 which concerns on this embodiment is 10 volume%-70 volume%. When the blending amount is less than 10% by volume, the electrical resistance value of the transparent conductor 20 tends to be higher than when the content is in the above range, and when the blending amount exceeds 70% by volume, Compared to the case where the content is in the above range, the mechanical strength of the conductive layer 12 tends to decrease.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

  For example, in the description of the method for manufacturing the transparent conductors 2a and 20, the resin and the curable resin 15a include those that can be cured by high energy rays, but can be cured by heat instead. A thing including a thing may be used.

Further, the transparent conductor 2a and 20, in addition to the touch panel is also as possible out using a panel switch such as an optical transmission switch.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

[Preparation of conductive powder]
An aqueous solution prepared by dissolving 19.9 g of indium chloride tetrahydrate (manufactured by Kanto Chemical Co., Ltd.) and 2.6 g of stannic chloride (manufactured by Kanto Chemical Co., Ltd.) in 980 g of water and aqueous ammonia (manufactured by Kanto Chemical Co., Ltd.) A white diluted product (co-precipitate) was produced by mixing with the one diluted twice.

  The liquid containing the generated precipitate was subjected to solid-liquid separation with a centrifuge to obtain a solid. This was further poured into 1000 g of water, dispersed with a homogenizer, and solid-liquid separation was performed with a centrifuge. After repeating dispersion and solid-liquid separation 5 times, the solid was dried and heated at 600 ° C. for 1 hour in a nitrogen atmosphere to obtain ITO powder (conductive powder).

(Example 1)
30 parts by mass of an acrylic polymer (average molecular weight of about 100,000) containing 20% by volume of ITO powder (average particle size 30 nm) and 2-hydroxy-3-phenoxypropyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: 702A) 35 parts by mass, 35 parts by mass of urethane-modified acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: UA-512) and 1 part by weight of UV polymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name: IRGACURE 907) Part and 50 parts by mass of methyl ethyl ketone (MEK) were mixed to obtain a paste.

The paste was applied onto a 50 mm square glass substrate by a spin coating method, and formed on one surface of the glass substrate so that the film thickness after MEK volatilization was 20 μm, to form a conductive layer. Further, a corona-treated surface of a 50 mm square polyethylene terephthalate (PET) film (base, manufactured by Teijin Ltd., thickness: 100 μm) having one surface subjected to corona treatment is bonded to this upper surface, and the integrated illuminance amount is 1000 mJ / cm ² . It was cured by UV irradiation using a high pressure mercury lamp as a light source.

  Then, the conductive layer is peeled off from the glass substrate, and a perfluoropolyether coating agent (fluorine compound, Shin-Etsu) diluted to 0.1 wt% with a fluorine solvent (trade name: FC-84, manufactured by 3M, USA) on the peeled surface. Chemical Industry Co., Ltd., product name: X-71-130) was applied by a dip coating method, the fluorine solvent was dried, and then left in an 85 ° C. and 85% RH environment for 5 hours to form a layer containing a fluorine compound did.

  Finally, in order to remove the excess fluorine compound on the layer containing the fluorine compound, the transparent conductor A was obtained by immersing in the fluorine solvent 5 times.

(Example 2)
The fluorine compound used in Example 1 was replaced with heptadecafluorodecyltrichlorosilane (manufactured by Shin-Etsu Chemical Co., Ltd.), and the reaction conditions were left at 85 ° C. and 85% RH for 5 hours to 100 ° C. for 1 hour. A transparent conductor B was obtained in the same manner as in Example 1 except that the above was changed.

(Example 3)
The fluorine compound used in Example 1 was changed to 1,8-bis (trichlorosilylethyl) hexadecafluorooctane (manufactured by Gelest), and the reaction conditions were left at 85 ° C. and 85% RH for 5 hours. Transparent conductor C was obtained in the same manner as in Example 1 except that the temperature was changed to stand at 100 ° C. for 1 hour.

( Reference example )
A 50 mm square polyethylene terephthalate (PET) film (base, manufactured by Teijin Ltd., thickness: 100 μm) was attached to a 50 mm square glass substrate using a double-sided adhesive tape, thereby fixing the base on the glass substrate.

  Next, a corona treatment was performed on one surface of the PET film, and a conductive layer was formed by RF sputtering so that the ITO layer had a thickness of 20 nm. And perfluoropolyether type coating agent (fluorine compound, manufactured by Shin-Etsu Chemical Co., Ltd., product name) diluted to 0.1 wt% on the ITO surface with a fluorine solvent (trade name: FC-84, manufactured by 3M USA) X-71-130) was applied by a dip coating method, and after the fluorine solvent was dried, it was left in an environment of 85 ° C. and 85% RH for 5 hours to form a layer containing a fluorine compound.

  Finally, in order to remove an excess fluorine compound on the surface of the conductive layer, the transparent conductor D was obtained by immersing in the fluorine solvent five times.

(Comparative Example 1)
A transparent conductor E was obtained in the same manner as in Example 1 except that the layer containing a fluorine compound was not provided in Example 1.

(Comparative Example 2)
The transparent conductor F was used in the same manner as in Example 2 except that the fluorine compound used in Example 2 was replaced with decyltrichlorosilane (manufactured by Shin-Etsu Chemical Co., Ltd.) and the diluent solvent was changed to n-hexane. Got.

[Evaluation methods]
The inclination angle when the brass weight started to move was measured by the following method.

  First, the obtained transparent conductors A to F were cut into a circle with a diameter of 25 mm, and a cylindrical brass weight (diameter 25 mm, 250 g) was bonded to the PET film surface using a double-sided adhesive tape to obtain weights A to F.

  Next, using a double-sided pressure-sensitive adhesive tape on the transparent film X (trade name: 300R, manufactured by Toyobo Co., Ltd., trade name: 300R) and a coating type transparent conductor E using a double-sided adhesive tape ( Affixed to an inclined plate of Toyo Seiki Seisakusho Co., Ltd.

Then, the weights A to F are inclined with respect to each friction measuring device so that the layer surface containing the fluorine compound of the weights A to F and the conductive layer surfaces of the transparent conductors X and E attached to the friction measuring device face each other. The inclined plate was inclined at an inclination angular velocity of 1 ° / sec. The inclination angle when the brass weight began to move was read, and this inclination angle was used for the evaluation of lubricity. The following numerical values are average values of the numerical values measured five times.

As is clear from Table 1, in Examples 1 to 3 in which a layer containing a fluorine compound was provided on the conductive layer, the brass weight began to move compared to Comparative Examples 1 and 2 that did not have a layer containing a fluorine compound. It was found that the tilt angle was small and the lubricity was excellent. From the above results, according to the transparent conductor of the present invention, it is considered that even if friction occurs between the transparent conductors, the surface of the transparent conductor can be prevented from being scraped and fluctuations in the electrical resistance value can be suppressed. It is done.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a touch panel 1 using a transparent conductor of the present invention. FIG. 2 is a schematic cross-sectional view showing the transparent conductor 2a. FIG. 3 is a schematic cross-sectional view showing the transparent conductor 20 used in the second embodiment of the touch panel of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Touch panel, 2a, 2b, 20 ... Transparent conductor, 11 ... Base | substrate, 12 ... Conductive layer, 12a ... Conductive powder, 13 ... Layer containing a fluorine compound.

Claims (9)

A substrate;
A conductive layer containing conductive powder and resin ;
A layer containing a fluorine compound;
With
Layer containing the fluorine compound, to the conductive layer is provided on the opposite side of the substrate, the thickness of the layer containing the fluorine compound is 1 to 50 nm,
Transparent conductor for touch panel . The transparent conductor for touchscreens of Claim 1 whose said fluorine compound is a linear molecule. The transparent conductor for touchscreens of Claim 1 with which the said fluorine compound has a side chain, and the fluorine atom is couple | bonded with the said side chain. The transparent conductor for touchscreens as described in any one of Claims 1-3 whose carbon atom number in the said fluorine compound is 5 or more. The transparent conductor for touchscreens as described in any one of Claims 1-4 in which the said fluorine compound has an ether bond. The transparent conductor for touchscreens as described in any one of Claims 1-5 in which the said fluorine compound has couple | bonded with the surface of the said conductive layer chemically. The transparent conductor for a touch panel according to claim 6, wherein the conductive layer contains conductive powder and a resin, and the conductive powder and the resin constitute the surface. The transparent conductor for touchscreens as described in any one of Claims 1-7 whose said fluorine compound is a perfluoro compound. A pair of transparent conductors facing each other;
A spacer provided between the pair of transparent conductors,
The panel switch whose at least any one is a transparent conductor for touchscreens as described in any one of Claims 1-8 among a pair of said transparent conductors.

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