JPS63454A - Production of transparent conductive film - Google Patents

Abstract

PURPOSE:To produce a transparent conductive film having high transparency and crystallinity and uniform performance by subjecting a transparent conductive layer which is formed on a transparent substrate and consists of a crystalline or low crystalline metal oxide to a heating treatment so as to improve the crytallinity thereof. CONSTITUTION:The transparent conductive layer consisting of the crystalline or low crystalline metal oxide such as In2O3 or SnO is formed by a method such as vapor deposition, sputtering or ion plating at a relatively low temp. of about 50-70 deg.C on the transparent substrate consisting of an inorg. material such as quartz glass or org. material such as PE terephthalate. The above- mentioned transparent conductive layer has preferably 1.3-1.5 deg. of oxidation and >=70% light transmittance at 550nm wavelength. The transparent conductive layer is then subjected to the heating treatment by blowing of hot wind, etc., for a short period of about 10-30min at a relatively low temp. of 130-200 deg.C to improve the crystallinity. The transparent conductive film having the transparent conductive layer which has the high transparency and high crystallinity and uniform performance is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the Wm It is about the method.

[Background of the invention]

In general, transparent conductive films allow devices to be made lighter and thinner than glass electrodes, are easy to handle during the manufacturing process, can be easily formed into a desired shape, and can be used continuously. Since it has various advantages such as ease of production, it is widely used as a conductive member for transparent switches, transparent electrodes of electroluminescent (EL) display boards, and other devices, for example.

Such a transparent IIM film is usually constructed by providing a transparent conductive layer made of a metal oxide on a sheet-like transparent substrate.For forming this transparent conductive layer, sputtering method, reactive vapor deposition, etc. have been conventionally used. Methods such as the post-heating oxidation treatment method (see Japanese Patent Laid-Open No. 48-55267), etc. have been adopted.

[Problem that the invention seeks to solve]

However, when forming a transparent conductive layer using a sputtering method or a reactive vapor deposition method, it is difficult to maintain a uniform temperature throughout the transparent substrate, so it is difficult to form a transparent conductive layer with uniform crystallinity. difficult to do. Therefore, when a transparent electrode of an electroluminescent display panel or a transparent electrode of a liquid crystal display element is formed using a transparent RN film, there is a problem in that the performance of the transparent electrode varies. In other words, in the manufacturing process of transparent electrodes, it is necessary to perform a process of dissolving the transparent conductive layer with acid etc. and patterning it, but in this process, the dissolution rate of the transparent conductive layer depends on the degree of crystallinity. As a result, the shape accuracy of the pattern becomes non-uniform, making it difficult to form a transparent electrode with high performance.

In addition, in the post-heat oxidation treatment method, a metal oxide is vacuum-deposited on a transparent substrate to form a metal oxide layer with a low degree of oxidation, and this metal oxide layer is further placed in an oxidizing atmosphere. This is a method of forming a transparent conductive layer with a high degree of oxidation by heat treatment. Therefore, in order to obtain a transparent conductive layer with a sufficiently high degree of oxidation, it is necessary to increase the heat treatment time or Alternatively, it is necessary to raise the treatment temperature.For example, when performing post-heating oxidation treatment in the atmosphere, it is necessary to raise the treatment temperature to 1.
At least 60 minutes of treatment at 80℃ is required, and when post-heating oxidation treatment in oxygen gas, 60 minutes of treatment at 130℃ is required.
A treatment time of at least 1 minute is required, resulting in a decrease in the productivity of the transparent conductive film and difficulty in forming a high performance transparent electrode. In addition, when the temperature of the transparent substrate is raised to, for example, about 150 to 300°C, and a transparent conductive material is formed on the substrate by vapor deposition or spuck method to form a transparent conductive layer with high crystallinity and degree of oxidation, When the transparent conductive film is then cooled to room temperature, a large stress is generated in the transparent conductive layer due to the difference in thermal expansion coefficient between the transparent substrate and the transparent conductive layer, so the transparent conductive layer is dissolved with acid etc. and patterned. In the process, the pattern portion is curved and the flatness is reduced.As a result, when used as a transparent electrode of a liquid crystal display element, there is a problem that the hue changes in the pattern portion and the transparency is reduced.

[Purpose of the invention]

The present invention was made based on the above circumstances, and its object is a method for manufacturing a transparent conductive film having a transparent conductive layer having high transparency, high crystallinity, and uniform performance. Our goal is to provide the following.

Means for Solving Problem C] The method for producing a transparent conductive film of the present invention includes a first step of forming a transparent conductive layer made of an amorphous or low-crystalline metal oxide on a transparent substrate; , a second step of heating the transparent conductive layer formed in the first step to increase the crystallinity of the transparent conductive layer.

[Function and effect of the invention]

According to the present invention, after performing the first step of forming a transparent conductive layer made of an amorphous or low-crystalline metal oxide on a transparent substrate, heat treatment is performed to improve the crystallinity of the transparent conductive layer. In the first step, a transparent conductive layer with a high degree of oxidation can be formed at a low temperature, and therefore a large stress is not applied to the transparent conductive layer due to the difference in thermal expansion coefficient between the transparent substrate and the transparent conductive layer. In addition, since the degree of oxidation is already sufficient in the first step, there is no need to particularly increase the degree of oxidation in the second step, and the heat treatment is performed in a short time and at a low temperature. By this, a transparent conductive layer with sufficiently high crystallinity can be obtained.

For example, a crystalline transparent conductive layer can be obtained by heat treatment at 130° C. for 30 minutes or 200° C. for 10 minutes in the atmosphere. The heat treatment can be performed by blowing hot air heated to a predetermined temperature onto the substrate, by bringing it into contact with a heating roll or flat plate, or by radiant heating using a sheathed heater or a heating lamp.

As a result, it is possible to produce a transparent conductive film having a transparent conductive layer with high transparency and uniform performance.
Various properties such as light transmittance become uniform, and as a result, a large number of transparent electrodes with uniform performance can be formed.

Therefore, in the process of dissolving and patterning a transparent conductive layer with an acid or the like when forming, for example, a transparent electrode of an electroluminescent display board or a transparent electrode of a liquid crystal display element, the rate of dissolution by the acid or the like becomes uniform, and High flatness can be obtained without curving, and as a result, a transparent electrode with high shape accuracy and high performance can be formed.

In addition, the high crystallinity of the transparent conductive layer improves the durability of the transparent conductive layer, and therefore, when forming a transparent switch for touch input, it has sufficient resistance even after repeated touch inputs of 1 million times or more. A transparent switch with good switching performance and excellent durability can be obtained.

[Specific structure of the invention]

The present invention will be explained in detail below.

In the present invention, a first transparent conductive layer made of an amorphous or low-crystalline metal oxide is formed on a transparent substrate.
After completing the first step, a second step is performed in which the transparent conductive layer obtained in the first step is heat-treated to increase the crystallinity of the transparent conductive layer, thereby making the transparent conductive layer transparent. Manufacture film.

In the present invention, a "transparent conductive layer made of an amorphous or low-crystalline metal oxide" means that the value of the (2.2.2) peak in X-ray diffraction is such that the transparent conductive layer is
Refers to the value of the peak (2.2.2) of less than 273 in the X-ray diffraction of the transparent conductive layer obtained when heat-treated at 80° C. for 30 minutes.

More specifically, in the first step, while the transparent substrate is maintained at a relatively low temperature of 50 to 70°C, an amorphous or low-crystalline metal oxide is placed on the transparent substrate. A transparent conductive layer is formed by, for example, vapor deposition. In this first step, since a metal oxide is used as the material for forming the transparent conductive layer, the transparent conductive layer obtained has a high oxidation degree, preferably 1.3 to 1.5, and therefore It will have sufficient transparency. In addition, the degree of oxidation refers to the metal oxide as M,
It is the ratio y/x when expressed as Oa. Furthermore, the transparent conductive layer obtained in the first step has a light transmittance of 550 wavelengths.
It is preferable that it is 70% or more in nm.

Next, in the second step, the transparent conductive film having the transparent conductive layer formed in the first step is heated in the atmosphere, in nitrogen gas, or in a vacuum at a temperature of 130 to 200°C, which is higher than the temperature in the first step. At a relatively low temperature of 3°C
Heat treatment is performed for a short time of about 0 to 10 minutes. In this heat treatment, the transparent conductive layer made of an amorphous or low-crystalline metal oxide gradually crystallizes, and finally becomes a highly crystalline transparent conductive layer.

As the material of the transparent substrate, various inorganic materials or organic materials can be used. Examples of the inorganic material include glasses such as quartz glass, soda glass, and potash glass. Examples of organic materials include polyethylene terecrate, polyethylene naphthalate,
Aromatic polyesters containing polyhexamethylene diamide, polyetherimide, polymethaxylene diamine terephthalamide, bisphenol A and its halides, and acid dichloride as main components (for example, rNAP Film J (1! manufactured by Fuchi Kagaku Co., Ltd.)) or aromatic Polyamides, polycarbonates, polypropylene, polyimides, polyamides, imidopolybenzimidazole, polyethersulfones, polyetheretherketones, polysulfones, polyetherimides, such as polyester carbonates, copolymers of metaphenylenediamine and isophthalic acid and terephthalic acid, etc. Examples include triacetylcellulose. In addition, the transparent substrate may have a polarizing filter function, and if stretching is required during manufacturing, it may be uniaxial or biaxial. Alternatively, any amorphous material can be used.

The thickness of the transparent substrate varies depending on the material, the purpose, etc., and cannot be generally specified, but for example, when used in a transparent switch, it is approximately 75 to 125 μm; For example, when used for a transparent electrode of a liquid crystal display element, the thickness is about 100 to 200 μm.

In the first step, metal oxides that can be used to form a transparent conductive layer made of an amorphous or low-crystalline metal oxide include, for example, indium oxide, tin oxide, and combinations of indium oxide and tin. Examples include a mixture, a mixture of tin oxide and antimony, a mixture of cadmium oxide and tin, and the like.

In forming this transparent conductive layer, a reactive vapor deposition method, a reactive svanta method, an ion blasting method, and other thin film manufacturing methods can be used. For example, when forming a transparent conductive layer by a reactive vapor deposition method, an appropriate heat source such as a resistance heating source or an electron gun heating source can be used as a heating source for the vapor deposition material.

In addition to these evaporation materials, other substances may be ionized or activated using a discharge device and placed in the evaporation space as materials for forming the transparent conductive layer or as aids in the formation of the transparent conductive layer. May be supplied. As such other substances, for example, oxygen, a mixed gas of oxygen and argon, etc. can be used. The supply amount of such other substances is, for example, 30 to 200 cc/l.
ll1n, and the degree of vacuum is 2X10-'~5
x 10-' Torr.

In a discharge device, for example, the output is 100 to 10
It is preferable that the above substance is ionized or activated by high frequency discharge of approximately 00W.

The thickness of the transparent conductive layer formed in the first step varies depending on its material, purpose, etc. - Although it cannot be generally specified, it is, for example, a transparent switch, a transparent electrode of an electroluminescent display board, a liquid crystal display element, etc. When used for transparent electrodes, the number is about 200 to 2000.

Heating means that can be used to heat-treat the transparent conductive layer in the second step include, for example, blowing hot air, radiant heating using a sheathed heater or halogen lamp, or thermal conduction through contact with a heating drum, heating plate, etc. Means such as heating can be mentioned. The temperature of the heat treatment is
Usually, it is preferably within the range of 130 to 200°C. If this heat treatment temperature is high, cranks will occur in the transparent conductive layer due to the difference in thermal expansion coefficient between the substrate and the transparent conductive layer, and There is a risk that some polymer films may be deteriorated by heat, and on the other hand, if the heat treatment temperature is low, the crystallinity of the transparent conductive layer will not be sufficiently high, resulting in a decrease in properties such as durability of the transparent conductive layer. There is a risk.

The time required for the heat treatment of the transparent conductive layer in the second step varies depending on the temperature of the heat treatment, but is usually 10 to 6 hours.
It is preferable that the duration is about 0 minutes. If the heat treatment time is too short, the crystallinity of the transparent conductive layer may be insufficient.

In the present invention, in addition to the transparent substrate and the transparent conductive layer, other layers may be provided as necessary to produce a transparent conductive film. Such other layers include, for example, a subbing layer for increasing the adhesion between the transparent conductive layer and the transparent substrate, a protective layer for preventing scratches on the transparent conductive layer, and a layer for preventing scratches on the transparent substrate. Alternatively, examples include a hard coat layer for preventing stains and the like, and a barrier layer for preventing deterioration of the transparent substrate by suppressing permeation of moisture, oxygen, etc.

Specific structural examples of the transparent conductive film are shown in FIGS. 1 to 7. In these figures, 90 is a transparent substrate, 91 is a transparent conductive layer, 92 is a subbing layer, 93 is a protective layer, 94 is a hard coat layer, and 95 is a barrier layer.

In the example shown in FIG. 1, a transparent conductive layer 91 is placed on a transparent substrate 90.
The example shown in FIG. 2 is a structure in which a subbing layer 92 is laminated on a transparent substrate 90, and a transparent conductive layer 91 is laminated on this subbing layer 92, the example shown in FIG. is a transparent substrate 9
In the example shown in FIG. 4, a hard coat layer 94 is laminated on one surface of a transparent substrate 90, and In the example shown in FIG. 5, which has a structure in which a subbing layer 92 and a transparent conductive layer 91 are laminated in this order on the other surface of the transparent substrate 90, a barrier layer 95 is laminated on one surface of the transparent substrate 90, and In the example shown in FIG. 6, in which a subbing layer 92 and a transparent conductive layer 91 are laminated in this order on the surface of a transparent substrate 90, on one surface of a transparent substrate 90,
The configuration in which a barrier layer 95 and a hard coat layer 94 are laminated on this I+[, and a subbing layer 92 and a transparent conductive layer 91 are laminated in this order on the other surface of the transparent substrate 90, is an example shown in red in FIG.
A barrier layer 95 and a transparent conductive layer 91 are laminated in this order on one surface of a transparent substrate 90, and a hard coat layer 94 is laminated on the other surface of the transparent substrate 90.

As the constituent materials of the undercoat layer 92, the protective layer 93, and the hard coat layer 94, various organic polymer substances and inorganic substances can be used. Examples of polymeric substances include thermosetting resins such as silicone resins, silane camping agents, silanol resins, epoxy resins, and melamine resins;
Examples include UV-curable resins such as acrylic resins. Examples of inorganic substances include silicon oxide, aluminum oxide, tin oxide, indium oxide, an indium-tin oxide mixture, zirconium oxide, tantalum oxide, niobium oxide, and cerium oxide. Further, as the undercoat layer made of an inorganic substance, an amorphous oxide substance such as amorphous tin oxide described in Japanese Patent Application No. 59-236443 can be preferably used.

As a constituent material of the barrier layer 95, for example, vinylidene chloride resin, ethylene vinyl alcohol copolymer resin, etc. can be used. In addition, specific products commercially available as ethylene vinyl alcohol copolymer resins include:
゛For example, rEVA-EP-FIOIJ, rEVA
-E P -F 104 J, rEVA-BP-F2
Examples include O3J (hereinafter referred to as ① manufactured by Kuraray). Inorganic substances can also be used, and examples of the inorganic substances include silicon oxide, aluminum oxide, indium oxide, and tin oxide.

These subbing layer, protective layer, hard coat layer, and barrier layer can be formed by, for example, a wire bar coating method, a gravure roll coating method, or the like. The thickness of the subbing layer is preferably about 0.1 to 5 pm for polymeric materials, and about 50 to 2,000 pm for inorganic materials. The thickness of the hard coat layer and protective layer is, for example, 1 to 1 pm for polymeric materials.
For inorganic substances, it is preferably about 500 to 2000 people. The thickness of a single barrier layer is, for example, about 5 to 30 um for polymeric materials, and 100 to 10 um for inorganic materials.
00 people is preferable.

FIGS. 8 and 9 are explanatory diagrams schematically showing an example of a manufacturing apparatus that can be used to carry out the present invention,
FIG. 9 shows a vapor deposition device for performing the first step, and FIG. 10 shows a heat treatment device for performing the second step.゛As shown in Fig. 8, the interior of the vapor deposition apparatus is divided into four chambers 11, 12, 13, and 14, each of which is maintained at a predetermined degree of vacuum by an exhaust pump (not shown). In the chamber IL 14, a supply roll 15 and a take-up roll 16 for film-like transparent substrates 10 are arranged, and the transparent substrate 10 from the supply roll 15 is transported by transport rollers 21, 22, 23, 24 and a vapor deposition roller 20 during processing. The film is wound up at a uniform speed by a winding roll 16 through the winding roller 16.

The chamber 13 defines a base space 17 for performing vapor deposition processing, and a vapor deposition roller 20 is provided above the chamber 13.
is arranged, and in the lower part, a vapor deposition material container 31, a vapor deposition material 32 stored in this container, a heat source (not shown) for heating and vaporizing this vapor deposition material 32, and a A discharge device 33 to be provided is arranged. From this discharge device 33, for example, a substance constituting the transparent conductive layer or a substance promoting the formation of the transparent conductive layer is supplied to the vapor deposition space 17 in an ionized or activated state.

The vapor deposition roller 20 is provided with a heater inside thereof (not shown in detail), and the transparent substrate 10 is brought into contact with the surface of the roller and is conveyed following the rotation of the vapor deposition roller 20.
For example, the structure is such that the temperature can be maintained within a range of 50 to 70°C.

As shown in FIG. 9, the heat treatment apparatus has three chambers 41.
A supply roll 51 of a transparent substrate 10 on which a transparent conductive layer made of an amorphous or low crystalline metal oxide formed through the first step is laminated is arranged in the chamber 41. A take-up roll 52 for the transparent substrate IO is arranged in the chamber 43. Reference numeral 60 denotes a heating mechanism, which includes, for example, a sheathed wire resistance heater, a halogen lamp radiation heater, a hot air heater, etc.
is located at the bottom of the. The transparent substrate 10 on which the transparent conductive layer is laminated from the supply roll 51 is wound up at a uniform speed by the take-up roll 52 via the transport rollers 53 and 54 during the heat treatment.

Using these 'Wiffs, a transparent conductive film can be manufactured, for example, in the following manner.

The transparent substrate 10 is supplied from the strategist process supply roll 15 via the conveyance rollers 21 and 22 and introduced into the vapor deposition space 17 so as to contact the surface of the vapor deposition roller 20 and follow the rotation of the vapor deposition roller 20. , while the temperature is maintained within the range of 50 to 70°C by the vapor deposition roller 20,
The vapor deposition material 32 made of a metal oxide is heated by a heat source and evaporated into the vapor deposition space 17, thereby forming a transparent conductive layer made of an amorphous or low-crystalline metal oxide on the transparent substrate 10.

In this case, an ionized or activated substance may be introduced into the vapor deposition space 17 from the discharge device 33 to be combined with the vaporized substance of the vapor deposition material 32 or to activate the vaporized substance.

The transparent substrate 10 on which the transparent conductive layer has been formed in this way is wound up onto a winding roll 16 via conveyance rollers 23,24.

The conveyance speed of the transparent substrate 10 is determined from the relationship with the growth rate of the transparent conductive layer, and for example, 50 to 200 c.
It is preferably within the range of m/min.

After the second step, the transparent substrate 10 on which the transparent conductive Ti layer is laminated is
The transparent material on the transparent substrate IO is introduced into the chamber 42 from the supply roll 51 via the conveyance roller 53, and maintained at a constant temperature within the range of 130 to 200° C. by the heating mechanism 60 in the chamber 42. The conductive layer is heat-treated, and then passed through a conveying roller 54 to a winding roll 52.
A transparent conductive film is manufactured by winding it up into a transparent conductive film.

In such an apparatus, a transparent conductive layer can be formed while continuously conveying the transparent substrate 10 at a uniform speed, so mass production is possible and transparent conductive films can be manufactured at low cost. Moreover, a transparent conductive film with uniform properties can be manufactured.

〔Example〕

Hereinafter, specific examples of the present invention will be described, but the present invention is not limited to these examples.

<Example 1> First step: On a film-like transparent substrate made of polyether sulfone with a thickness of 100 μm, a film made of amorphous tin oxide with a thickness of 5
Amorphous or A transparent conductive layer having a thickness of 500 mm and made of indium-tin oxide (tin content = 6% by weight) with low crystallinity was formed.

The obtained film is referred to as "Film A".

The degree of oxidation of this film A is about 1.3, and the composition ratio is IntOz,b. In addition, the light transmittance for light with a wavelength of 550 nm is 84%, and the sheet resistance is 250 nm.
It was Ω/mouth.

Note that the oxidation degree of the transparent conductive layer was determined by the ESCASC method. The results of the ESCA analysis are shown in FIG. 10. Based on the results of the ESCA analysis, In: +d, 5nxa,
08. The height of each peak is measured, and each of these peak heights is divided by the correction value shown in Table 1 below, and the obtained I
nxa, 5n34.07. The ratio of In, ,
The oxidation degree was calculated using the following formula using the concentration of SnsO (at%).

Oxidation degree = 01. Concentration/Inxa Concentration Table 1 Also, when the transparent conductive layer of the above film A was examined by X-ray diffraction, the value of the (2.2.2) peak in X-ray diffraction was found to be This is about 10% or less of the peak value of (2.2.2) in the X-ray diffraction of the transparent conductive layer obtained when heat-treated for 30 minutes at l+1!, indicating that the crystallinity is low. 2nd step The film A obtained in the 1st step was placed at atmospheric pressure,
Heat treatment was performed at a temperature of 130° C. for 30 minutes, thereby obtaining a transparent conductive film according to the present invention.

This is referred to as "transparent conductive film 1".

When the transparent conductive layer in this transparent conductive film 1 was examined by X-ray diffraction, as shown in FIG.
It was confirmed that the transparent conductive layer had high crystallinity, and it was confirmed that the crystallinity of the transparent conductive layer was high.
When the degree of oxidation was measured based on the results of SCA analysis, it was approximately 1
．． 3 was the same as before the heat treatment, and it was confirmed that there was almost no change.

The transparent conductive film l obtained as described above was 2C
When the sheet resistance and light transmittance for light at a wavelength of 550 ns were measured for each small piece after dividing it into I11×2C11 pieces, the sheet resistance was 200±5.
0. Ω/mouth and high uniformity, and optical i3 pass rate is 84±1
%, and the uniformity was high.

On the transparent conductive layer of the transparent RM film obtained as described above, resist ink "Aqua resist ink" is applied.
(manufactured by Jujo Kakosha) by screen printing method.
Print a pattern with a line width of 1 ma+, then at a temperature of 90
The resist ink was dried by heat treatment at .degree. C. for 60 minutes.

Next, this was immersed in a hydrogen bromide (HBr) aqueous solution (25°C, concentration 45-50% by weight) for 20 seconds to dissolve the exposed part of the transparent conductive layer in 1 liter, then washed with water, dried, and then treated with an alkaline solution. The resist film was removed by , followed by washing with water and drying to form a line-shaped electrode made of a transparent conductive layer.

When the obtained linear electrode was observed under a microscope, it was confirmed that the shape accuracy was uniform and the flatness was high (an excellent transparent electrode).

Switching resistance properties A transparent switch for touch input was produced in accordance with practical use using the transparent conductive film 1 obtained as described above,
An experiment was conducted to examine the keystroke resistance of these transparent switches using an experimental apparatus having the configuration shown in FIG. In this FIG. 12, 70 is a DC power supply, 71 is a resistor, and 80
is a transparent switch, one transparent conductive layer 81 of the transparent switch 80 is connected to the positive electrode of the DC power source 70 via a resistor 71, and the other transparent conductive layer 82 of the transparent switch 80 is directly connected to the negative electrode of the DC power source 70. has been done. 72 is a key-pressing section. 83 and 84 are one and the other transparent substrates, respectively, and 85° and 86 are spacers. Transparent substrate 8
The thickness of 3.84 is 125μ, the thickness of transparent conductive layer 81.82 is 500, and the length D of gap 87 is 0.5m.
It is m. In the experiment, the transparent switch 80 was repeatedly opened and closed by reciprocating the key-pressing part 72 up and down, and even after about 1.5 million times, the T flowing through the transparent switch
It was confirmed that there was no disturbance in the L flow waveform and still good switching characteristics were obtained, and that the mechanical durability was excellent and the keystroke resistance was sufficient. Note that the switching current is In+A and the voltage is 5■. Further, the keying portion is provided at its tip with a spherical rubber keying portion having a rubber hardness of 6 degrees and a diameter of 8 degrees.

<Example 2> A transparent conductive film was produced in the same manner as in Example 1 except that the heat treatment temperature in the second step was changed as shown in Table 2 below.

Further, a transparent conductive film was produced in the same manner as above except that the atmosphere in the heat treatment in the second step was nitrogen gas.

For each of these transparent conductive films, the crystallinity of the transparent door T and layer was examined by X-ray diffraction.

The results are also shown in Table 2.
”, “△”, and “×” evaluations are as follows.

rOJ: The value of the (2.2.2) peak in X-ray diffraction is the value of (2.2. 2) is 2/3 or more of the peak value.

"Δ": The value of the (2.2.2) peak in X-ray diffraction is the value of (2. It shows that it is less than 2/3 of the peak value of 2.2).

rXJ: Indicates that no peak is observed in X-ray diffraction.

Table 2 From the results in Table 2, it is understood that crystallization of the transparent conductive layer progresses sufficiently when the heat treatment temperature is 130° C. or higher.

In addition, in the same manner as in Example 1, a transparent switch for touch input was manufactured, and a test was conducted to examine the anti-switching characteristics.
The number of keystrokes that could be tolerated before switching became defective was determined.

The results are also shown in Table 2.

As can be understood from the results in Table 2, when using a transparent 474 film with a heat treatment temperature of 130°C or higher in the second step, the mechanical resistance is 100,000 times or more. 'ffl F! has excellent durability.
did it. On the other hand, when a transparent conductive film is used in which the heat treatment temperature in the second step is 120°C or lower, the number of keystrokes is low at about 100,000 to 700,000 times, resulting in poor mechanical durability. Ta.

<Example 3> First step Using an apparatus having the configuration shown in FIG. 8, a transparent conductive layer with a thickness of 400 μm was formed on a film-like transparent substrate made of polyethylene terephthalate with a thickness of 100 μm according to the following conditions. , with a sheet resistance of 300 to 400 Ω/hole and a light i3 pass rate of 80 to 83 for light at a wavelength of 550 nm.
%, and the degree of oxidation of the transparent conductive layer was 1.3 to 1.5. This will be referred to as "Film C".

In addition, when the crystallinity of the transparent conductive layer in this film C was examined by X-ray diffraction, it was found that (2.2.
2) The peak value is 3
It was about 10 to 20% of the value of the peak (2.2.2) in the X-ray diffraction of the transparent conductive layer obtained when heat-treated for 0 minutes.

0Surface temperature of evaporation roll: 50-70℃Of deposition material: Indium-tin oxide (ITO) 0Heating method of evaporation material: Electron gun heating method 0Evaporation rate = 100-500 people/min0Discharge device: High frequency discharge device (Frequency - 13,56MHz, discharge power -300~50
0W) 0 Gas introduced from the discharge device: Oxygen gas (gas pressure = 2 Xl0-' to 3 Xl0-' Torr
)yJ2 process Using the apparatus configured as shown in Figure 9, the film C obtained in the first step was heated at a temperature of 150°C for 3
A transparent conductive film according to the present invention was obtained by heat treatment for 0 minutes. This is called “Transparent Conductive Film 3”
shall be.

- When the crystallinity of the transparent conductive layer in this transparent conductive film 3 was examined by X-ray diffraction, it was found that (
2.2.2) The peak increases and its value is determined by (2.2.2) in the X-ray diffraction of the transparent conductive layer obtained when the transparent conductive layer is heat-treated at a temperature of 180°C for 30 minutes.
The size was approximately 80% of the peak value, and it was confirmed that the crystallinity was sufficiently high.

The sheet resistance, light transmittance, and degree of oxidation of the transparent conductive film 3 were also examined, and they were almost the same as those of the film C obtained in the first step, with almost no change observed in these properties.

Characteristic tests similar to those in Example 1 were performed on the transparent conductive film 3 obtained as described above, and the sheet resistance was highly uniform at 350±50Ω/hole, and the light transmittance was also 82±1. %, and the uniformity was high.

Furthermore, when a patterning test similar to that in Example 1 was conducted using the transparent '-7ie film 3 obtained as described above, the shape accuracy of the obtained linear electrodes was uniform; It was also confirmed that the transparent electrode had high flatness and was excellent.

In addition, a transparent switch for touch input was fabricated using the transparent conductive film 3 in the same manner as in Example 1, and a test was conducted to examine the switching resistance characteristics, and the number of keystrokes that could be tolerated before switching became defective was determined. , keystroke resistance is 15
It was confirmed that the product had excellent JRtJ durability, exceeding 00,000 cycles.

For comparison, a transparent switch for touch input was fabricated in the same manner using Film C obtained in the first step, and the number of key presses was investigated. It was of inferior quality.

In addition, when a transparent conductive film was produced in the same manner as above except that the heat treatment temperature in the second step was changed to 150°C, a transparent conductive film having almost the same performance as the above-mentioned transparent conductive film 3 was obtained. It was done.

[Brief explanation of drawings]

FIGS. 1 to 7 are explanatory cross-sectional views showing specific structural examples of transparent conductive films, respectively, and FIG. 8 is a schematic diagram of an example of a manufacturing apparatus that can be used to carry out the first step in the present invention. FIG. 9 is an explanatory cross-sectional view schematically showing an example of a manufacturing apparatus that can be used to perform the second step in the present invention, and FIG.
E to determine the degree of oxidation of the transparent conductive layer formed in the process
An explanatory diagram showing the results of SCA analysis, Fig. 11 is an explanatory diagram showing the results of X-ray diffraction for examining the crystallinity of the transparent conductive layer obtained in the second step, and Fig. 12 is an explanatory diagram showing the results of X-ray diffraction for examining the keystroke resistance. FIG. 2 is a diagram showing an example of an experimental device in use. 90...Transparent base 91...Transparent conductor': 4
．． Layer 92... Subbing layer 93... AI protection layer 94... Hard coat layer 95... Barrier layer 1
1.12, 13.14... Chamber 10... Transparent substrate 15... Supply roll 16... Take-up roll 20... First arrival roller 21.22, 23.24... Conveyance roller 31 ... Vapor deposition material container 32... Vapor deposition material 33... Discharge device 17... Vapor deposition space 41.42.43...
- Chamber 51... Supply roll 52... Take-up roll 60... Heating mechanism 53.54... Conveyance roller 70... DC power supply 71... Resistor
72... Key stick 80... Transparent switch
81.82...Transparent conductive layer 83, 84...Transparent base 85.86...Spacer 87...Gap

Claims (1)

[Claims] 1) A first step of forming a transparent conductive layer made of an amorphous or low-crystalline metal oxide on a transparent substrate, and heating the transparent conductive layer formed in this first step. A method for producing a transparent conductive film, comprising a second step of treating the transparent conductive layer to increase crystallinity. 2) The degree of oxidation of the transparent conductive layer in the first step is 1.3 to 1.
．． 5. The method for producing a transparent conductive film according to claim 1, wherein the transparent conductive film has a light transmittance of 70% or more at a wavelength of 550 nm. 3) The temperature of the heat treatment in the second step is 130 to 200
The method for producing a transparent conductive film according to claim 1 or 2, characterized in that the temperature is .degree.