JPH11232940A - Manufacture of transparent conductor and transparent conductive film thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily provide a transparent conductive material with an arbitrary pattern at a low temperature by applying chemical treatment and/or light energy for patterning surface polarity of a transparent base body and applying hydrophilic/hydrophobic liquid containing conductive material onto the surface for forming the conductive material into a shape which is in matching with the patterning. SOLUTION: As a transparent film arranged on a transparent base body, a polymer film showing adhesiveness with the base body or a photosensitive polymer, such as resist polymer is used. In optical patterning, various kinds of light beams are radiated via a photomask, and the surface characteristic can be patterned. For a light beam, an ultraviolet beam, an electron beam, a laser beam, a glow discharge light beam, or an arc discharge light beam is preferable. In chemical patterning, patterned photoresist etching is carried out on a hydrophilic base body, and then a hydrophobic liquid containing a conductive material is added, for example.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for applying a conductive material and a film obtained by the method. In particular, the present invention relates to a method for easily producing a transparent conductor.

[0002]

2. Description of the Related Art Conventionally, conductive materials transparent to visible light have been used as electrodes for display devices such as liquid crystal display devices and electroluminescence devices, and as electromagnetic wave shielding materials such as CRTs. As such a transparent conductive material, for example, tin oxide / antimony oxide (ATO) and indium oxide / tin oxide (ITO) are known. These metal oxides form a film on a glass or ceramic substrate to give a transparent conductive film. As a method for forming such a transparent conductive film, for example, a vacuum evaporation method, a sputtering method, a CVD method, a coating method, and the like are known.

[0003]

Among the above methods, the vacuum deposition method, the sputtering method, and the CVD method have problems in cost and production because the film formation method is complicated and expensive. In addition, various sol-gel methods have been proposed as coating methods, but these methods are still insufficient in performance. On the other hand, when applying the metal oxide in an arbitrary pattern, means such as so-called photolithography or printing may be used, but the former requires safety and health, such as that a strong acid must be used for etching the metal oxide. There is a problem in that the latter is not suitable for a fine pattern in terms of printing accuracy.

When higher conductivity is required,
In some cases, so-called silver paste is used, or a mesh-like woven fabric with metal plating on fibers is used for electromagnetic wave shielding.The former requires high-temperature heat treatment at 500 ° C or higher, and is usually used for resin film supports. It is not suitable, and the latter has a problem that the process is special and complicated, and an arbitrary pattern cannot be obtained. Accordingly, an object of the present invention is to provide a method for easily applying a transparent conductive material in an arbitrary pattern at a low temperature (200 ° C. or lower).

[0005]

The above object is achieved by the present invention described below. The surface polarity of the transparent substrate is patterned by chemical treatment and / or application of light energy, and a hydrophilic or hydrophobic liquid containing a conductive material is applied to the surface to form a shape corresponding to the patterning. A method for producing a transparent conductor, comprising forming a conductive material. 4. The method for producing a transparent conductor according to claim 1, wherein the transparent substrate is a transparent film support or a transparent film support coated with a transparent coating film. The method for producing a transparent conductor according to or above, wherein the light energy is selected from ultraviolet light, electron beam, laser light, corona discharge light, and glow discharge light.

The method for producing a transparent conductor according to any one of claims 1 to 3, wherein the conductive material is obtained by heating a metal-containing compound represented by the following general formula (I). Formula (I) (R. (C≡C) n) k- (L)-(A) m (In the above formula (I), A represents a polyoxyether group, a polyaminoether group, or a polythioether group. R represents a metal element, L represents a chemical bond or a (k + m) -valent group connecting a carbon-carbon triple bond and A. k and n are each an integer of 1 or more.
m is an integer greater than or equal to zero. )

The conductive material is obtained by heating a metal-containing compound represented by the following general formula (II) in the presence of a Group 8 or 1B element of the periodic table. A method for producing a transparent conductor. Formula (II) (R · (C≡C) n) k- (L)-(A) m (In the above formula (II), A represents a polyoxyether group, a polyaminoether group, or a polythioether group. R represents a metal element, a hydrogen atom, a carboxyl group or a salt thereof, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, or a heterocyclic group, and L represents a carbon-carbon triple bond. Represents a chemical bond or a (k + m) -valent group linking A. k and n
Is an integer of 1 or more. M is an integer of 0 or more. )

[0008] The method for producing a transparent conductor according to any one of the above, wherein the conductive material is a metal or an oxide semiconductor. The method for producing a transparent conductor according to any one of claims 1 to 3, wherein the patterning is performed in a grid pattern. A transparent conductive film, wherein the substrate produced by the method described in any one of the above is a film.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to embodiments of the present invention. The transparent substrate used in the present invention may be anything as long as it is substantially transparent.
Transparent synthetic resin film, for example, acrylic resin, vinyl chloride resin, styrene resin, polyurethane resin, melamine resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, polycarbonate resin,
Polyolefin resin, polyacrylonitrile resin,
Polyarylate resin, fluorine resin, silicone resin,
A thermoplastic resin such as a cellulose resin, a polysulfone resin, a polyvinyl alcohol resin, a norbornene resin, a thermosetting resin, a photocurable resin, or the like is used. Specifically, polyethylene terephthalate,
Polyethylene naphthalate, polypropylene, polyethylene, polyamide, polycarbonate, polyacrylonitrile, polyarylate, polyvinyl chloride, cellulose triacetate, cellulose diacetate, polyether sulfone, polymethyl (meth) acrylate, and the like are used. The thickness of these resin films is 10 μm to 50
0 μm is preferable, and 50 μm to 200 μm is more preferable.

Any transparent polymer film may be used as the transparent coating film provided on the transparent substrate. For example, an acid is generated on the surface by light or cross-linked to change the polarity or affinity. Alternatively, the speed of the liquid containing the conductive material can be changed by crosslinking. Examples include a polymer film exhibiting easy adhesion to the substrate, such as a so-called undercoat layer, and a photosensitive polymer such as a positive or negative photoresist polymer. These polymer films may be a single film or a multilayer film. The thickness of these polymer films is preferably from 0.001 μm to 10 μm, more preferably from 0.01 μm to 2 μm.

As an optical patterning method, various light beams are irradiated through a so-called photomask to apply light energy to pattern the surface characteristics. Glow discharge light, arc discharge light, and the like, as well as ultraviolet light, gamma rays, X-rays, electron beams, visible light, infrared light, and laser light, are used as light rays. Ultraviolet light, electron beam, laser light, glow discharge light and arc discharge light are preferred. For example, a part of a bond on a surface having hydrophobic polarity can be cut by light irradiation, or the surface can be made hydrophilic by rotation of the bond or polar group.

Although any method may be used for chemically patterning the substrate, for example, a patterned photoresist is etched on a hydrophilic substrate and then a hydrophobic liquid containing a conductive material is applied. For example, a method may be used in which a patterned photoresist is etched on a hydrophobic substrate, and then a hydrophilic liquid containing a conductive material is applied. In this way, the conductive material can be provided after forming the hydrophilic / hydrophobic pattern on the substrate surface. According to the present invention, a pattern in which conductors are continuous can be formed by forming a pattern with dots and using a liquid that repels the points.

Next, the conductive material to be applied will be described. The conductive material used in the present invention may be a substance having conductivity or a compound exhibiting conductivity by a treatment such as heating. Tokiko 7-537 as conductive material
The compounds listed in No. 77 are used. That is, a compound which is a compound represented by the following general formula (I) but exhibits conductivity when heated is obtained. Formula (I) (R. (C≡C) n) k- (L)-(A) m (In the above formula (I), A represents a polyoxyether group, a polyaminoether group, or a polythioether group. R represents a metal element, L represents a chemical bond or a (k + m) -valent group connecting a carbon-carbon triple bond and A. k and n are each an integer of 1 or more.
m is an integer greater than or equal to zero. )

Further, a compound which exhibits conductivity even when a metal-containing compound represented by the following general formula (II) is heated in the presence of a Group 8 or 1B element of the periodic table is obtained. Formula (II) (R · (C≡C) n) k- (L)-(A) m (In the above formula (II), A represents a polyoxyether group, a polyaminoether group, or a polythioether group. R represents a metal element, a hydrogen atom, a carboxyl group or a salt thereof, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, or a heterocyclic group, and L represents a carbon-carbon triple bond. Represents a chemical bond or a (k + m) -valent group linking A. k and n
Is an integer of 1 or more. M is an integer of 0 or more. )

The general formulas (I) and (II) will be further described. As the metal elements in the general formulas (I) and (II), excluding hydrogen, excluding group 1A (alkali metal), group 1B (copper group), group 2A (alkaline earth metal), group 2B (zinc group), and boron Group 3B, 4B excluding carbon and silicon
Group, group 8 (iron group and platinum group), group 3A, group 4A, group 5A
Group, 6A and 7A and antimony, bismuth and polonium. Examples of Group 8 elements in the periodic table that are present when the compound represented by the general formula (II) is used include nickel, ruthenium, rhodium, palladium, platinum, and the like. Examples of Group 1B elements include copper and silver. , Gold. Among them, R in the general formulas (I) and (II) is preferably a silver atom. In this case, the bond between the silver atom and the carbon-carbon triple bond may be a σ bond or a π bond. Good. In particular, in the case of a π bond, a silver mirror film can be formed as described later in detail.

In the general formulas (I) and (II), L represents carbon-
A chemical bond or a (K + m) -valent group connecting a carbon triple bond and A, for example, an alkylene group each of which may be substituted,
Arylene group, aralkylene group, vinylene group, cycloalkylene group, glutaroyl group, phthaloyl group, hydrazo group, ureylene group, thio group, carbonyl group, oxy group,
It represents an imino group, a sulfinyl group, a sulfonyl group, a thiocarbonyl group, an oxalyl group, an azo group, etc., and may be a combination of two or more of these.

A and L are each
It may be substituted with a hydroxyl group, an amino group, a mercapto group, a sulfino group or a salt thereof, a sulfo group or a salt thereof, a carboxyl group or a salt thereof, or a polymerizable group. Examples of the polymerizable group include a glycidyl group, a vinyl group, an isocyanate group, and the like. Further, the alkyl group, cycloalkyl group, alkenyl group, alkynyl group, aryl group, aralkyl group and heterocyclic group as R in the general formula (II) may be substituted. k and n are integers of 1 or more, and preferably k is 1 to 4 and n is 1 or 2. In addition, m is an integer of 0 or more, and preferably 1 to 3. As mentioned above,
The compound represented by the general formula (I) or (II) contains at least one of a polyoxyether group, a polyaminoether group and a polythioether group in its molecule. In particular, it preferably contains a polyoxyether group. By using an acetylene compound having such a group, the compound itself has high solubility in an organic solvent as a “mixture with a metal element”, and thus has a uniform film or fiber form. A metal-containing polymer can be easily obtained. Preferred specific monomers are listed below, but are not limited thereto.
Further, in the present invention, a metal salt monomer may be used.

[0018]

Embedded image

The acetylene compound as these monomers can be generally synthesized as follows. That is, compounds having a carbon-carbon triple bond, for example, propiolic acid, propargyl bromide, compounds having other necessary functional groups such as propargyl alcohol, and the like, for example, tetraethylene glycol monoethyl ether, maleic anhydride, butane sultone, epichlorohydrin And acrylic acid chloride may be condensed.

The following is an example of the synthesis method. Synthesis of Exemplified Compound (1) Tetraethylene glycol monoethyl ether 107
g, propargyl bromide 107 g, anhydrous potassium carbonate 300
g of the mixture was heated and stirred on a water bath for 20 hours. After cooling,
The insolubles are cooled and filtered, and the filtrate is distilled under reduced pressure. Yield 1
20 g, colorless and transparent liquid, boiling point 115 ° C./3 mmHg Further, those having a metal element as R are (H- (C≡C) _l )
It can be easily obtained by reacting an acetylene compound represented by _k- (L)-(A) _m with a corresponding metal salt of the above-mentioned element by a known method. For example, those having silver as R preferably used in the present invention can be prepared by mixing silver nitrate, silver acetate or silver tetrafluoroborate with the acetylene compound as the above monomer in an appropriate solvent such as water or methanol. Obtainable. The silver salt may be a σ complex, a π complex or a mixture thereof. Such a metal salt such as a silver salt can be identified by an NMR spectrum and an IR spectrum.

"Group 8 or 1B element of the periodic table" to be present when the compound represented by the general formula (II) is used.
Is used as a metal salt or a metal complex. As such a metal salt, silver nitrate, silver acetate, silver tetrafluoroboronate, palladium chloride, cuprous chloride, platinum chloride and the like are preferable. These metal complexes include di-μ-chlorobis (η
-2-methylallyl) dipalladium (II) complex, tetrakis (triphenylphosphine) palladium complex, di-
μ-chlorotetracarbonyldirhodium (I) complex,
Examples thereof include 1,4,7,10,13-pentaoxycyclododecane / sodium tetrachlorpanadinite, dicyclopentadiene-gold (I) chloride, and the like. The molar ratio of the monomer to the metal salt or metal complex is 1: 1:
0.5 to 1: 4, preferably 1: 1 to 1: 2. As described above, in the present invention, a metal-containing polymer may be formed using a monomer, or a dimer, trimer, oligomer, or the like of these compounds may be used. Further, two or more monomers may be used.

When using the above general formulas (I) and (II), any solvent may be used as long as it can be dissolved. In addition to water, hydrophilic solvents such as alcohols such as methanol, acetone and methyl ethyl ketone Ketones, such as chloroform, halogen compounds such as methylene chloride, esters such as ethyl acetate, amides such as dimethylacetamide, dimethylformamide, N-methyl-2-pyrrolidone, and nitriles such as acetonitrile. Is used. The conductive material need not necessarily be dissolved in the solvent, and may be dispersed. The solids concentration in these solutions or dispersions is 0.1-80%, preferably 20-70%
It is. The heating temperature after the application is preferably from 80 to 200 ° C. Although depending on the heat resistance of the support, a higher temperature is advantageous for conductivity, and a lower temperature is not affected by the deformation of the support.

The hydrophilic liquid or the hydrophobic liquid containing the conductive material of the present invention can be mainly classified into a solution or a dispersion using the above-mentioned hydrophilic solvent or hydrophobic solvent. However, the terms hydrophilic solvent and hydrophobic solvent are used in chemical common sense, but there is no strict classification. for that reason,
The invention can be realized by using a liquid having an affinity for the pattern from the operation of the present invention. The conductive material is
It is preferable to use the material at the above-mentioned concentration, including the above-described materials and the materials described below.

As the conductive material, fine particles of an oxide having conductivity may be used. For example, as an oxide semiconductor having conductivity, In ₂ O ₃ , SnO ₂ , ZnO, CdO, TiO ₂ , CdIn ₂ O ₄ , In
_{Although 2} O ₃ -ZnO and the like are used, in particular, tin-doped indium oxide (ITO), Sb-doped SnO ₂ , Al-doped ZnO, and the like are widely used as having particularly good transparency. The amount of the element to be doped is preferably 1 to 15% by weight. In addition to these oxides, conductive materials such as TiN and
ZrN, nitrides such as HfN, borides such as LaB _6, MgIn
There are spinel compounds such as O ₄ and CaGa ₄ . These conductive materials are preferably used as fine particles. The size of the fine particles is from 1 nm to several hundreds μm, but is preferably several tens nm or less from the viewpoint of transparency. The shape may be any shape such as a needle shape or a layer shape other than a spherical shape, but a spherical shape is preferred.

A metal colloid solution may be used as the conductive material. Au, Ag, Pd, Pt, R
So-called noble metals such as h, Ru, Ir, Os are preferred. These fine metal particles are dispersed in the solution without agglomeration or precipitation, and the particle size of the colloid varies depending on the type, but is about 10 to 200A. A trace amount of a surfactant or a protective colloid may be added for imparting stability of the colloid.
Although various methods have been reported for synthesizing metal colloids, a method of reducing a metal salt solution with a reducing agent such as sodium borohydride or hydrazine to form a metal is generally used. In addition, a metal paste such as silver or copper can be used as the conductive material.

The transparent conductive film of the present invention can be used for a transparent electrode for a display, a light control device, a battery, a touch panel, and various other transparent conductive films. It is preferably used as a shield filter. In particular, when used as an electromagnetic wave shielding film, in order to impart conductivity and increase transparency, it is preferable to apply a conductive material in a lattice pattern. The grid line width at this time is 20 to 10
Preferably, the opening spacing is about 50 to 600 μm. The wider the line width and the smaller the spacing, the higher the electromagnetic wave shielding effect, but the lower the transparency,
Conversely, the narrower the line width and the greater the spacing, the lower the electromagnetic wave shielding effect but the better the transparency. In the present invention, the lattice shape does not need to be a regular lattice pattern composed of vertical and horizontal straight lines, and may be composed of a curved line. What is necessary is just to make sure that the portion where the conductive material does not exist does not exist in the form of dots. Further, the higher the transparency of the conductive material itself, the better the transparency as a film. Settings can be made according to the purpose. The grid can be provided by the method for applying a conductive layer material according to the present invention.

[0027]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Example 1 A mesh filter having a line width of 100 μm and a spacing of 300 μm, prepared by photo-etching a steel foil having a thickness of 40 μm, was brought into close contact with one side of a 100 μm-thick polyethylene naphthalate (PEN) film. Pressure 0.2 Torr, partial pressure of H ₂ O in atmosphere gas 75%, discharge frequency 30 kHz, output 2500 W, processing intensity 0.5
Glow discharge treatment was performed at kV · A · min / m ² . The above P
The EN film was bar-coated with a liquid having the following composition using a # 5 bar, and heat-treated at 170 ° C. for 3 minutes. As a result, a silver-containing polymer was deposited in the same pattern as the above-mentioned steel foil mesh grid filter grid. Compound Example (1) 280 g AgNO ₃ powder 220 g Toluene 70 g The surface conductivity of the portion of the lattice pattern film where the silver-containing polymer is continuously formed without being glow-irradiated is measured by a four-probe method. The measurement showed 1 Ω / □. Further, the transmittance of the entire grating portion was measured.
%Met.

[0029]

As described above, according to the present invention, there is provided a method for easily applying a transparent conductive material in an arbitrary pattern at a low temperature (200 ° C. or less) instead of at a high temperature (200 ° C.) as in the prior art. You.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Taku Nakamura 210 Nakanakanuma, Minamiashigara, Kanagawa Prefecture Fuji Photo Film Co., Ltd.

Claims (8)

[Claims] 1. Patterning the surface polarity of a transparent substrate by applying a chemical treatment and / or applying light energy, and applying a hydrophilic liquid or a hydrophobic liquid containing a conductive material to the surface. A method for producing a transparent conductor, comprising forming a conductive material in a shape corresponding to the above. 2. The method for producing a transparent conductor according to claim 1, wherein the transparent substrate is a transparent film support or a transparent film support provided with a transparent coating. 3. The method according to claim 1, wherein the light energy is selected from ultraviolet light, electron beam, laser light, corona discharge light, and glow discharge light. 4. The method for producing a transparent conductor according to claim 1, wherein the conductive material is obtained by heating a metal-containing compound represented by the following general formula (I). . Formula (I) (R. (C≡C) n) k- (L)-(A) m (In the above formula (I), A represents a polyoxyether group, a polyaminoether group, or a polythioether group. R represents a metal element, L represents a chemical bond or a (k + m) -valent group connecting a carbon-carbon triple bond and A. k and n are each an integer of 1 or more.
m is an integer greater than or equal to zero. ) 5. The conductive material is obtained by heating a metal-containing compound represented by the following general formula (II) in the presence of a Group 8 or 1B element of the periodic table. Item 4. The method for producing a transparent conductor according to items 1 to 3. Formula (II) (R · (C≡C) n) k- (L)-(A) m (In the above formula (II), A represents a polyoxyether group, a polyaminoether group, or a polythioether group. R represents a metal element, a hydrogen atom, a carboxyl group or a salt thereof, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aryl group, an aralkyl group, or a heterocyclic group, and L represents a carbon-carbon triple bond. Represents a chemical bond or a (k + m) -valent group linking A. k and n
Is an integer of 1 or more. M is an integer of 0 or more. ) 6. The method for producing a transparent conductor according to claim 1, wherein the conductive material is a metal or an oxide semiconductor. 7. The method for producing a transparent conductor according to claim 1, wherein the patterning is performed in a grid pattern. 8. A transparent conductive film, wherein the substrate produced by the method according to claim 1 is a film.