KR20180028601A - Method for Screening a Conductive Laminate in Roll to Roll process - Google Patents

Abstract

The present invention relates to a method for screening a conductive laminate in a roll-to-roll process for forming a conductive laminate. According to the present invention, the method for screening a conductive laminate by using an in-situ way can be accomplished by measuring and comparing change degrees of resistance values measured in each step of forming a conductive laminate through a roll-to-roll coating way and simultaneously forming a conductive laminate.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of screening a conductive laminate in a roll-

The present application relates to a method for selecting a conductive laminate in a roll-to-roll process. More particularly, the present invention relates to a method of manufacturing a conductive laminate, and a method of preliminarily screening unusable fabrics by grasping whether the conductive laminate is defective or not.

The electrochromic device refers to a device that uses a phenomenon in which the color of an electrochromic material changes due to an electrochemical oxidation / reduction reaction. The electrochromic device may have a structure in which an electrochromic layer having an electrochromic material is laminated on one surface of an electrode layer. The electrochromic device may have a structure in which charge particles are inserted / can do.

On the other hand, the driving characteristics such as the discoloration rate of the electrochromic device largely depend on the resistance between the electrode layer or the laminate of the electrode layer and the electrochromic layer. Since the factors of increase in the resistance of the electrode layer or the laminate vary, it is difficult to limit all the factors for increasing the resistance, but it is necessary to measure and manage the resistance of the minimum electrode layer or the laminate. In this connection, a method of measuring the resistance of an ITO transparent electrode formed on a base film through sputtering, for example, is generally performed in terms of quality verification (QC) regarding delivery specifications. However, It is impossible to sufficiently prepare for the increase of the resistance of the sieve and the deterioration of the driving characteristics of the electrochromic device.

Furthermore, in order to produce a high-speed, high-volume production of components, a method of applying a coating solution containing an electrochromic material on an electrode fabric to be unwound, that is, a method of producing a laminate of an electrode layer and an electrochromic layer by a roll- The resistance of the electrode layer can be greatly increased due to the physical and chemical reaction between the coating material and the electrode. Therefore, a method for preventing the defective operation of the device due to the increase in the resistance of the electrode is needed.

An object of the present invention is to provide an electrochromic device improved in the problem of poor driving of the device due to an increase in the resistance of the electrode during the manufacturing process.

The above and other objects of the present application can be all attained by the present application which is described in detail below.

In one example of this application, the present application relates to a method of screening conductive laminates. The conductive laminate according to the present invention is a concept corresponding to an electrode or a counter electrode used in an electrochromic device or a battery. The conductive laminate is formed of a conductive material, that is, formed on a surface of an electrode layer, May refer to a structure having a separate layer.

The method of selecting the conductive laminate of the present application can be performed in an in-situ manner. Specifically, the screening method of the present application can be performed by forming the conductive laminate through the roll-to-roll coating method and measuring and comparing the degree of change of the resistance value measured at each step of forming the conductive laminate have. Specifically, in the method of selecting the conductive laminate of the present application, the resistance value (R1) of the rewound conductive substrate before application of the coating solution is measured, and the resistance value of the conductive substrate (R2 ), Measuring the resistance value (R3) of the conductive base material after the heat treatment for the coating solution, and comparing the measured resistance values. The term " resistance " in the present application may be a line resistance (Ω / cm) or a sheet resistance (Ω / □) measured on a conductive substrate or a conductive laminate and may be measured manually or automatically using a known device .

With respect to the roll-to-roll process, the point of time when the resistance value is measured in the present application will be described in detail as follows.

First, the resistance value R1 of the conductive substrate that has been re-wired from any one of the rolls can be measured. The conductive substrate on which the resistance value R1 is measured can be transported through the transport means, and the coating solution can be applied on the conductive substrate at the same time as the transport, or the conductive substrate can be transported to a specific point and then applied. The conveying means of the conductive substrate is not particularly limited and can be achieved through a known roll-to-roll system. The means for applying the coating solution on the conductive substrate is also not particularly limited, and application of the coating solution to the substrate may be performed using a known means such as a slot die.

After application of the coating solution, a resistance value (R2) measurement on the conductive substrate with the coating solution applied before the heat treatment mentioned below can be additionally performed.

Thereafter, a heat treatment process can be performed on the conductive base material on which the resistance value R2 is measured. The heat treatment may be a step of providing a separate coating layer on the conductive substrate by evaporating the solvent of the coating solution or hardening the curable resin contained in the coating solution. The heat treatment conditions are not particularly limited, and may be, for example, a temperature at which the coating solvent is evaporated or a temperature at which the curable resin can be cured. More specifically, the heat treatment may be performed at a temperature ranging from 50 ° C to 150 ° C, but is not particularly limited thereto. In addition, the heat treatment may be performed by a separate heater during the roll-to-roll process.

The method of selecting the conductive laminate according to the present application can be performed in consideration of the ratio between the resistance values measured in the above step. Specifically, when the coating solution is applied on a conductive substrate, the resistance of the conductive substrate increases due to a physical and chemical reaction between the coating material and the conductive substrate. Therefore, the present application relates to a method of manufacturing a resist- The defective fabric which lowers the durability of the device can be screened in advance, taking into account the ratio between the resistance values of the previous steps.

In one example, the method of the present application can be made by confirming whether [Relation 1] below is satisfied or not.

[Relation 1]

R3 / R2? 2

When the applied coating solution is subjected to a heat treatment, the resistance value of the conductive substrate with respect to the resistance before the heat treatment is greatly increased. Since the conductive laminate is directly used as a component of the electrochromic device or the battery, it is confirmed whether or not the difference in resistance value before and after the heat treatment for the coating solution satisfies the above relational expression May be particularly important for ensuring the durability of the element or the battery. Accordingly, in the method of the present application, only the conductive base material satisfying the above-mentioned relational expression 1 or the laminate thereof can be used for the production of devices and batteries.

In another example, the method of the present application can be made by confirming whether [Relation 2] below is satisfied or not.

[Relation 2]

R2 / R1? 1.5

Even when the coating solution is applied onto the conductive substrate, the resistance may be higher than the resistance value measured before application of the coating solution, although the resistance of the conductive base material after the heat treatment for the coating solution is not increased. It is preferable to confirm whether or not it is. When the above expression (2) is satisfied, the probability of satisfying the expression of the above expression (1) can be further increased.

The resistance value of the conductive base material may vary depending on the kind and content of the substance coated on the conductive base material, physical stress applied to the conductive base material during the roll-to-roll process, and the like. However, since the present application provides only the conductive laminate satisfying the relational expressions 1 and / or 2 to the device or the battery use, the present invention is not limited to the device or the durability- Battery can be provided. Furthermore, the present application makes it possible to confirm at which step of the process of manufacturing a conductive laminate, a problem such as an increase in resistance is caused.

The kind of the substance forming the conductive substrate is not particularly limited. For example, a transparent conductive metal oxide or a metallic material known as a low resistance metal may be used to form the conductive substrate.

In one example, a transparent conductive metal oxide used for the conductive base material is ITO (indium tin oxide), In 2 O 3 (indium oxide), (indium galium oxide) IGO, FTO (fluor doped tin oxide), AZO (aluminium doped zinc oxide (GZO), antimony doped tin oxide (ATO), indium doped zinc oxide (IZO), niobium doped titanium oxide (NTO), zinc oxide (ZnO), or cesium tungsten oxide (CTO) Can be used.

In one example, the low resistance metals used for the conductive substrate include metals such as silver (Ag), copper (Cu), aluminum (Al), magnesium (Mg), gold (Au), platinum (Pt), tungsten Molybdenum (Mo), titanium (Ti), nickel (Ni), or an alloy containing them may be used. The low resistance metal may form an electrode in the form of a mesh, or may be included in a conductive substrate in the form of nanowires.

In one example, the electrode including the low-resistance metal may be formed of OMO (Oxide / Metal / Oxide) in which a metal layer formed of a low-resistance metal is interposed between the layers constituted of the above-mentioned conductive oxide.

In another example, the conductive substrate may further include graphene or carbon nanotubes. For example, the conductive base material may be immersed in a solution in which graphene and / or carbon nanotubes are dispersed, or a solution in which graphene and / or carbon nanotubes are dispersed is sprayed onto a conductive substrate Graphene and / or carbon nanotubes may be coated or adsorbed onto the conductive substrate. Electrodes further comprising graphene or carbon nanotubes can be further improved in conductivity. The content of graphene and carbon nanotubes is not particularly limited, but may be used within a range that does not lower the transparency of the electrode.

In one example, a translucent substrate may be provided on a surface opposite to one surface of the conductive substrate provided with the coating layer formed after the heat treatment. Specifically, it may further include a light-transmitting substrate having a transmittance of about 50% to 90% with respect to visible light. The visible light may mean an optical wavelength in the range of approximately 380 nm to 780 nm.

The type of the light-transmitting base material is not particularly limited, and transparent glass or polymer resin can be used, for example. More specifically, a polyester film such as PC (Polycarbonate), PEN (poly (ethylene naphthalate)) or PET (poly terephthalate), an acrylic film such as poly (methyl methacrylate) Or a polyolefin film such as polypropylene (PP), but the present invention is not limited thereto.

In one example, the coating solution may comprise an organic solvent, an additive, and a electrochromic material.

In one example, as the organic solvent, an aqueous or alcohol-based solvent which can be evaporated through heat treatment after application of the coating solution can be used.

In one example, a known organic or inorganic binder may be used as the additive.

In one example, an organic or inorganic electrochromic material may be used as the electrochromic material. In a non-limiting example, pyridine-based compounds, aminoquinone-based compounds, polythiophene, viologen, and the like can be used as organic electrochromic materials. As the inorganic electrochromic material, at least one of oxides of Ti, V, Nb, Ta, Mo, W, Co, Rh, Ir, Ni, Cr, Mn and Fe may be used.

The method of applying the coating solution to the conductive substrate is also not particularly limited. Methods applicable to the roll-to-roll process can be used without limitation, for example, spin coating, dip coating, spray coating, gravure coating, flow coating, slot die coating or bar coating.

Since the conductive laminate selecting method of the present application employs an in-situ method, a conductive laminate is formed through a roll-to-roll coating method and a conductive laminate capable of improving the durability of the electrochromic device or the battery is provided can do.

Hereinafter, the present application will be described in detail by way of examples. However, the scope of protection of the present application is not limited by the embodiments described below.

Manufacture of Half-Cell

Example  One

The ITO / PET substrate samples were prepared in the same size (10 cm x 15 cm), and the coating solution was applied and heat treated to simulate the in-situ type conductive laminate selecting method in the roll-to-roll process according to the present invention. Of an electrochromic layer. The coating solution was composed of Prussian blue (PB) particles, water, and alcohol. The coating solution was coated by a bar coating method and then heat-treated at 130 ° C for 3 minutes.

Example  2 to 8 and Comparative Example  1 to 6

A coating liquid of the same composition was applied, and an electrochromic layer having the same thickness was formed under the same conditions. However, a commercially available product was used for the ITO, but the manufacturers of the examples and the comparative examples were different.

resistance measurement

Resistance of each step was measured using HIOKI 3244. Specifically, line resistances R1, R2, and R3 were measured in half-cell fabrication processes of the Examples and Comparative Examples. R 1 is the resistance value of ITO in the ITO / PET substrate before application of the coating solution, R 2 is the resistance value of ITO in the ITO / PET substrate immediately after application of the coating solution, and R 3 is the resistance value of the electrochromic layer / ITO / It is the resistance value of ITO in the PET laminate. The resistance values measured in each of the examples and the comparative examples are as shown in [Table 1].

Drive evaluation

The half-cell was immersed in a liquid electrolyte (1 M LiClO ₄ in PC) and applied to the same electrode for each cell. The half-cell was applied with a three electrode system in which the reference electrode was Ag / AgCl and the counter electrode was Pt. , And a driving characteristic was evaluated. The driving characteristics were measured by whether the switching of the detachment color was smooth and whether the charge amount was changed. The results are as shown in [Table 1].

[Table 1]

As shown in Table 1, in the case of Examples 1 to 8, since the stepwise resistance value satisfies 1 and 2 in the above-mentioned relationship, it can be confirmed that the drive characteristics are good. However, in the case of Comparative Examples 1 to 6 in which the star resistance values do not satisfy the relational expressions 1 and 2, it can be confirmed that the drive is not performed at all or is very poor. This is because the resistance of the conductive base material is increased beyond a certain level in the manufacturing process of the conductive laminate, so that the driving characteristic of the device is deteriorated due to the voltage drop due to the resistance.

Also, through the above experiment, it can be confirmed that the increase in the resistance value of the conductive substrate, which affects the deterioration of the driving characteristics of the electrochromic device, mainly occurs in the heat treatment step for the coating solution applied on the conductive substrate during the roll- .

Claims (12)

The resistance value (R1) of the rewound conductive substrate before application of the coating solution was measured,
After the application of the coating solution, the resistance value (R2) of the conductive substrate is measured,
After the heat treatment for the coating solution, the resistance value (R3) of the conductive base material is measured,
And comparing the measured resistance values.
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
The method according to claim 1, further comprising the steps of:
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
[Relation 1]
R3 / R2? 2
3. The method according to claim 2, further comprising the step of:
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
[Relation 2]
R2 / R1? 1.5
3. The method of claim 2, wherein the conductive substrate comprises a transparent conductive metal oxide, wherein the transparent conductive metal oxide is ITO (indium tin oxide), In 2 O 3 (indium oxide), (indium galium oxide) IGO, FTO (fluor doped tin oxide (AZO), gallium doped zinc oxide (GZO), antimony doped tin oxide (ATO), indium doped zinc oxide (IZO), niobium doped titanium oxide (NTO) , Or CTO (cesium tungsten oxide)
Method for screening conductive laminates in a roll-to-roll process for forming conductive laminates
3. The method of claim 2, wherein the conductive substrate comprises a metal mesh or nanowire.
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
6. The method of claim 5, wherein the metal mesh or nanowire comprises a low resistance metal and the low resistance metal is selected from the group consisting of Ag, Cu, Al, Mg, Au, (Pt), tungsten (W), molybdenum (Mo), titanium (Ti), nickel (Ni)
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
5. The electro-optical device according to claim 4, wherein the conductive substrate is OMO (Oxide / Metal / Oxide) in which a metal layer formed of a low-resistance metal is interposed between two layers composed of the transparent conductive metal oxide, ), Copper (Cu), aluminum (Al), magnesium (Mg), gold (Au), platinum (Pt), tungsten (W), molybdenum (Mo), titanium (Ti) Lt; / RTI >
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
3. The method of claim 2, wherein the conductive substrate further comprises graphene or carbon nanotubes.
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
3. The method of claim 2, wherein the coating solution comprises an organic solvent, an additive, and a electrochromic material.
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
The electrochromic material according to claim 9, wherein the electrochromic material comprises at least one oxide selected from oxides of Ti, V, Nb, Ta, Mo, W, Co, Rh, Ir, Ni, Cr,
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
The method of claim 2, wherein the coating solution is applied by spin coating, dip coating, spray coating, gravure coating, flow coating, slot die coating or bar coating.
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.
3. The method of claim 2, wherein the heat treatment is performed at a temperature in the range of 50 DEG C to 150 DEG C,
A method for screening conductive laminates in a roll-to-roll process for forming conductive laminates.