JPH056768B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a substrate having a novel transparent conductive circuit, and its purpose is to simplify the manufacturing process compared to conventional etching methods, lift-off methods, etc. The present invention relates to an economically advantageous method of manufacturing a substrate having a transparent conductive circuit of excellent quality. Products according to the present invention include liquid crystal displays, electromic displays, electrophotographic recording bodies, electrophoretic recording bodies, transparent switches, connectors, flexible circuits, antistatic bodies, sheet heating elements, solar cells,
The present invention provides a transparent conductive film that is useful as a material for conductors in various industrial fields including the electrical and electronic industries. The following method is known as a method of manufacturing a substrate having a transparent conductive circuit. That is, metal thin films such as gold, silver, palladium, tin oxide,
A thin film of metal oxide such as indium oxide, antimony oxide, cadmium tin oxide, etc. is formed on the entire surface of a glass substrate, plastic substrate, sheet substrate, or film substrate by vacuum evaporation, sputtering, or printing, and then the necessary conductivity is formed. A masking layer for the circuit is formed on the digital circuit part by photoresist method or screen printing method, and then unnecessary metal thin film pattern part or metal oxide thin film pattern part is removed by wet or dry etching method, and then masking is performed. By removing the layer, a transparent conductive circuit is formed. However, these methods had the following drawbacks. That is, when forming a masking layer with photoresist, coating of photosensitive resin,
Processes such as pattern baking, development, and photoresist removal are required, resulting in poor workability, and when forming a masking layer with resist ink using the screen printing method, production is slow due to the long drying time required. It had problems such as poor performance and the need for a variety of expensive materials, and was also subject to various limitations in terms of equipment and work. As an example of a method for solving this problem, a thickened etching solution described in JP-A-58-113376 is applied directly to the conductive thin film through a silk screen, and then washed with water, etc. A method of etching a desired pattern using a process has been proposed, but in a follow-up experiment conducted by the inventors
With this method, the etching effect after application of the etching solution cannot be fully confirmed or guaranteed from the appearance, or the reliability of adjusting the holding time after application and washing with water is extremely low, and there is a possibility that the etching is not completed. If water washing is performed beforehand, there is a risk that unnecessary parts will be eroded, and it is difficult to ensure reproducibility in actual industrial production. It was recognized that there was a strong tendency to lower the quality of products, and that there were many difficult problems in the product inspection process and work management. On the other hand, in the case of the lift-off method, unnecessary pattern parts on the substrate are printed in advance using, for example, water-soluble ink, and then a thin metal film or a thin metal oxide film is formed on the entire surface of the substrate, and then washed with water. A method has been devised in which a desired transparent conductive circuit can be obtained by removing the water-soluble ink pattern using a method that eliminates the need for an etching process from an industrial perspective. This makes the work considerably easier, but although it is an excellent method for mass production, it tends to pose economical problems when producing a wide variety of products in small quantities. In view of the current situation, the inventors of the present invention have spent many years researching ways to solve the above-mentioned problems of the conventional technology, and as a result of their dedicated efforts, they have formed the desired transparent conductive circuit on a substrate. We have finally completed the present invention as a new and remarkable method for achieving this. In this method, a desired pattern is formed on a transparent conductive film using an aqueous color-changing ink containing an acidic compound and a coloring substance, and then the etching is completed by the ink changing color as the reaction progresses. They discovered that by visually checking the ink, then washing off the ink with water and drying it, it was possible to form transparent conductive circuits with a precision and beauty not seen with conventional methods.Based on this knowledge, they developed various techniques. After investigating the raw material-related conditions and work procedures, the present invention was finally completed. That is, the present invention provides at least one oxidized group selected from the group consisting of a sulfoxy group, a sulfone group, a sulfin group, a sulfenic acid group, a sulfonic acid group, a phosphenic acid group, a phosphonic acid group, a phosphoric acid group, a sulfuric acid group, and a fluorine-containing condensed acid group. A pattern is printed on a transparent conductive film containing a heavy metal component on the surface of a resin substrate using a water-based color-changing ink containing a compound and a coloring substance, and after visually confirming the discoloration of the ink, the pattern portion is washed with water to remove it and dried. The present invention clarifies a method for manufacturing a substrate having a transparent conductive circuit characterized by the following. The present invention will be explained in detail below. Sulfoxy group, sulfone group in the present invention,
sulfinate root, sulfenate root, sulfonate root, phosphenate root, phosphonate root, phosphate root,
The acidic compound containing at least one acid group selected from the group consisting of a sulfate group and a fluorine-containing condensed acid group preferably satisfies the following conditions. That is, those that react quickly with the transparent conductive film and perform accurate etching, those that have good dispersion and solubility to produce gels and precipitates as much as possible when mixed into the ink binder, and those that can be quickly removed by washing. etc. are preferred. Now, specific compounds of such acidic substances include the following. In other words, the molecular formulas of typical compound examples are: CH ₃ SOCH ₂ COOH, C ₆ H ₅ SOCH ₂ COOH, SO
(CH ₂ CH ₂ COOH) ₂ , C ₆ H ₅ SO C ₆ H ₅ COOH,
C ₆ H ₅ SOC ₆ H ₄ CH ₂ COOH, CH ₃ SO ₂ C ₂ COOH,
C ₆ H ₅ SO ₂ COOH, SO ₂ (CH ₂ CH ₂ COOH) ₂ ,
C ₆ H ₅ SO ₂ C ₆ H ₄ CH ₂ COOH, C ₆ H ₅ SO ₂ H, CH ₃ ,
_{CH3C6H4SO2H , C6H5SOH , CH3C6H5SOH , _ _ _
CH3SO3H , CF3SO3H , C6H5SO3H , _
CH3C6H4SO3H , NH2SO3H , C6H5NHSO3H , _ _ _}
H ₂ SO ₃ H, HOC ₆ H ₄ SO ₃ H, (HO) ₂ C ₆ H ₃ SO ₃ H,
C ₁₀ H ₇ C ₁₀ H ₆ SO ₃ H, HOC ₁₀ H ₆ SO ₃ H, C ₆ H ₄
( _SO3H ) _{2 , CH3C6H3 ( SO3H ) 2} , _HOC6H3
( _SO3H ) ₂ , _{( HO} ) _{2C6H2SO3H ,}
(HO) ₂ C ₁₀ H ₅ SO ₃ H, (HO) ₂ C ₁₀ H ₄ (SO ₃ H) ₂ ,
_{ClC6H4SO3 , NO2C6H4SO3 , Cl2C6H3SO3H , _ _ _ _ _}
CF ₃ C ₆ H ₄ SO ₃ H, C ₆ H ₅・C ₆ H ₄ SO ₃ H,
HSO ₃ C ₆ H ₄ C ₆ H ₄ SO ₃ H, CH ₂ (C ₆ H ₄ SO ₃ H) ₂ ,
CH ₂ (HOC ₆ H ₃ SO ₃ H) ₂ , CH ₃ CH
(HOC ₆ H ₃ SO ₃ H) ₂ , (CH ₃ ) ₂ C (HOC ₆ H ₃ SO ₃ H),
(CH ₃ O) ₂ P (OH) ₂ , (C ₂ H ₅ ) ₂ P (OH) ₂ , (C ₆ H ₅ ) ₂ P
(OH) ₂ , _CH3OP (OH) ₂ , _{C2H5OP (} OH) ₂ ,
_C6H5OP ( _OH ) ₂ , _{CH3PO ( OH} ) ₂ , _C2H5PO2
(OH) ₂ , C ₆ H ₅ PO ₂ (OH) ₂ , H ₃ PO ₄ , NaHPO ₄ ,
_{Na2HPO4 ,} ( _NH4 ) _{H2PO4 ,} ( _NH4 ) _{2HPO4 ,
H2SO4} , _NaHSO4 , _{KHSO4 , CH3OSO2OH ,
C2H5OSO2OH , C6H5OCO2OH , HBF4 , HPF6 ,}
HSbF ₆ , H ₃ AlF ₆ , H ₂ TiF ₆ , H ₂ ZrF ₆ , NaFH ₂ ,
KHF ₂ , (NH ₄ )HF ₂ , R ₄ NHF ₂ , H ₃ TiF ₇ ,
H ₂ SiF ₆ or the like alone or in a mixture of two or more. Furthermore, various acidic derivatives and acidic salts based on each of these compounds, such as sulfoacetic acid, lithium sulfosalicylate borofluoride, ammonium borofluoride, onium hydroborofluoride, humic hydroborofluoride, and fluorophosphate. , onium fluorophosphate, onium polyfluorometallate, alkylbenzenesulfonic acids, akenylbenzenesulfonic acids, phenolsulfonic acids, cresolsulfonic acids, xylenolsulfonic acids, naphthalenesulfonic acids,
Anthracenesulfonic acids, phenanthrenesulfonic acids, naphtholsulfonic acids, halogenbenzenesulfonic acids, nitrobenzenesulfonic acids, alkoxybenzenesulfonic acids, hydroxybenzenesulfonic acids, olefinic acid adducts,
Benzene polysulfonic acid, naphthalene polysulfonic acid, and the like are also suitable compounds for the present invention, and they can be used alone or as a mixture. The sulfoxy group, sulfone group, sulfinate group, sulfenate group, sulfonate group, phosphenate group, phosphonate group, phosphate group shown above,
According to the results of experiments conducted by the present inventors, acidic compounds that do not contain at least one acid group selected from the group consisting of sulfuric acid radicals and fluorine-containing condensed acid radicals do not meet the present invention even when applied to the method of the present invention. The expected excellent effects as shown in the figure could not be exhibited (in this regard, it is necessary to conduct preliminary tests as shown in Comparative Examples 1 to 3). The amount of the acidic compound mentioned above in the present invention should not be particularly regulated, but it is generally desirable that it be included in the range of 20 to 50 parts by weight based on 100 parts by weight of the binder in the ink. . If the amount is less than 20 parts by weight, the etching speed will be slow and the discoloration image will become slow, which will be inconvenient for work. If the amount exceeds 50 parts by weight, undesirable side etching may occur during etching, the ink may not be easy to manufacture or store, and printability may be impaired. Next, the color-changing ink according to the present invention will be explained. The term "color-changing ink" as used herein refers to one that contains, as a coloring substance, a compound that changes color due to a change in pH or a compound that changes color due to the formation of an insolubilized substance. For example, compounds that change color due to changes in pH are:
It is a reagent that senses and detects changes in hydrogen ion concentration on the acidic side. Specific examples of such reagents include methyl violet, methanyl yellow, metacresol purple, p-xylenol blue, and motyl blue tropaeolin. , benzopurpurin
4B, quinaldine red, methyl yellow, blum phenol blue, tetrabromo phenol blue, methyl orange, brom chlorophenol blue, α-naphthyl red, alizarin sulfonic acid alkali, blum cresol green, methyl red, chlorphenol red, benzoyl auramine G, Bromcresol purple, bromphenol red, bromthymol blue, etc. alone or a mixture thereof, including bromcresol purple 0.05% + bromthymol blue 0.05%
The color changes to yellow to purple (acid to alkaline) at pH 6.7, and bromcresol green 0.075% +
It is known that 0.05% methyl orange changes color from orange to green (acid to alkaline) at pH 4.3. A compound that changes color due to the formation of an insolubilized substance refers to a compound that dissolves the transparent conductive film component and binds or adsorbs it to the components in the ink to generate a poorly soluble substance, specifically producing a white precipitate. Examples include aromatic carboxylic acids or their alkali salts, alkylbenzoic acids or their salts, aromatic sulfonic acids or their alkali salts, naphthalenecarboxylic acids or their salts, alkylnaphthalenecarboxylic acids or their salts, and colored pillows. Those that cause phlegm include mercaptans, mercaptides,
Examples include thiophenols, sulfur-containing amino acids, and dyes containing carboxyl or sulfoxy groups. Ink components other than the above-mentioned acidic substances and color-changing compounds include general-purpose binders suitable for various printing methods for this color-changing ink,
It contains a solvent (organic solvent or water), a surfactant, an antifoaming agent, and additives, and is processed so that it can be used as an ink. In addition, the printing used in the present invention includes screen printing, gravure printing, flexographic printing, offset printing, letterpress printing, and the like. Regarding the resin substrate referred to in the present invention, various resin sheets or various resin films can be used, but
In particular, polyester film and polyamide film are preferred for printing. The transparent conductive film containing heavy metal components of the present invention preferably has conductivity and transparency, such as metal thin films of gold, silver, platinum, palladium, copper, etc., tin oxide, indium oxide, Thin films of metal oxides include antimony oxide, titanium oxide, zirconium oxide, indium oxide-tin oxide, and tin oxide-antimony oxide, but considering etching processability and economic efficiency, indium oxide,
Those based on tin oxide seem to be the most preferred. The thickness of these transparent conductive films is 10 Hz to 500 Å, and the resistance value is 1 Ω/□ to 10 ⁴ Ω/ depending on the application of the electric circuit.
□, especially preferably 10Ω/□~
2000Ω/□ is good. Further, cleaning methods include shower cleaning using water or a polar solvent, cleaning in a bathtub, ultrasonic cleaning, microwave cleaning, and the like. At this time, care must be taken not only to completely remove ink residues that impede the transparency of the transparent conductive circuit, but also to avoid damaging the surface of the transparent conductive circuit. From this point of view, shower cleaning is an industrially preferred method, but in this case, it is desirable that the water pressure is 1 kg/m ² or more, and if it is 1 kg/m ² ,
It seems to be difficult to obtain accurate etched designs. Furthermore, before the subsequent drying step, it is advisable to wash and drain the material using a sponge roller or the like, and care should be taken to ensure that drying is carried out efficiently in a dehydrating air stream. The present inventors conducted a large number of experiments regarding the method of the present invention described above and confirmed the superiority of the present invention.In order to further explain the technical content of the present invention, representative examples are shown below. This will be shown as an example. It goes without saying that the method of the present invention should not be construed solely as being limited to the examples shown below, and that the embodiments thereof can be carried out as appropriate. Example 1 A biaxially stretched polyethylene terephthalate film (thickness 0.1 mm, 550 nm parallel light beam 87%) was
Indium/tin oxide having a composition of indium oxide: tin oxide = 90:10 was deposited by a sputtering method. Sputtering was performed at a vacuum level of 10 ^-3 torr with argon gas introduced, and the deposited film thickness was approximately 100 Å.
It was hot. Next, for 100g of sodium alginate, add 30g of CF ₃ SO ₃ H and 75% of bromcresol green.
mg and 50 mg of methyl orange were added, diluted with an equal amount of ethanol-water mixed solvent to make a total amount of about 300 g,
Created an ink suitable for silk screening. Using this ink, the above-mentioned thin film ink was prepared.
This ink is used to print the line width on the thin film mentioned above.
50.0mm, line spacing 1.0mm or 51.0mm pitch length
Ten 100mm thin lines were printed. After one minute, the color of the ink changed from orange to greenish. The film is then washed with water to completely remove the ink and then dried. For each thin wire, the surface resistance between both ends is
The resistance was 500Ω/□, and the insulation between each thin wire was perfect. Examples 2 to 10 Copper was deposited on a commercially available nylon film (thickness: 25 μm) by vacuum evaporation. Adhesive film pressure is approximately 3000
It was Å. On the other hand, 150 g of an aqueous color-changing ink containing 4 g of the aliphatic carbonyl cleavage-containing acidic compound shown in the attached table and 100 mg of the coloring reagent was prepared for 10 g of the synthetic resin shown in the attached table 1. Using this ink, 150 designs with a line width of 1.27 mm, a line spacing of 1.27 mm, or a pitch of 2.54 mm and a length of 50 cm were printed on the copper surface of the nylon film by gravure printing. After 5 to 20 minutes, the color change of the ink was completed, and the film was washed with water to completely remove the ink, and then dried.The surface resistance was measured, and the results shown in Attached Table 1 were obtained. Example 11 and Comparative Examples 1 to 3 Metals shown in Attached Table 2 were deposited to a thickness of 500 Å on a biaxially stretched polyethylene terephthalate film (thickness: 50 μm) by vacuum deposition. Next, 100g of high molecular weight polyethylene glycol,
Apply an ink containing 40g of the acidic compound shown in Attached Table 2, 300g of water, and 50mg of the color-changing reagent shown in Attached Table 2.
After leaving it for 30 minutes and confirming that the discoloration was complete, it was washed with water to completely remove the ink, dried, and then the surface resistance was measured to test the etching effect, and the results shown in Attached Table 2 were obtained. In Comparative Examples 1 to 3, the etching effect was poor because the combination of the deposited metal, the acidic compound, and the color-changing reagent was inappropriate. Since such unpredictable events may occur, combinations must be selected through sufficient preliminary testing. 【table】

Claims (1)

[Claims] 1. An acidic substance containing at least one acid group selected from the group consisting of a sulfoxy group, a sulfone group, a sulfinate group, a sulfenic acid group, a sulfonic acid group, a phosphenic acid group, a phosphonic acid group, a phosphate group, a sulfuric acid group, and a fluorine-containing condensed acid group, and a coloring. A pattern is printed on a transparent conductive film containing a heavy metal component on the surface of a resin substrate using a water-based color-changing ink containing a substance, and after the discoloration of the ink is visually confirmed, the pattern is removed by washing with water and dried. A method for manufacturing a substrate having a transparent conductive circuit.