KR20180052191A - A Conductive Film and Method for Preparing the Same - Google Patents

Abstract

The present invention relates to a conductive film and to a manufacturing method thereof. In the present application, since moving particles can be confined by a simple process, the manufacturing process can be simplified and the manufacturing cost can be reduced. In addition, since the qualities of micelles containing conductive particles can be increased for a long time, the durability reliability of products can be improved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a conductive film,

The present application relates to a conductive film and a method of manufacturing the same.

When the electrically driven cell includes charged particles or liquid crystal, a barrier is used to confine the charged particles or liquid crystal in a certain space inside the cell. Such barrier ribs are formed by patterning a polymer layer provided on a substrate, and photolithography, photoresist, or mold printing or the like is generally used for the patterning. However, the above-described process of forming the barrier ribs complicates the fabrication process, increases the manufacturing cost, and causes damage to the electrodes during the process.

On the other hand, although emulsions have been used in various fields, there is a problem that it is difficult to maintain the dispersion stability of droplets as dispersed phases for a long time.

One object of the present invention is to provide a conductive film containing liquid crystal or charged particles without forming a barrier rib.

Another object of the present invention is to provide a method of manufacturing a conductive film in which the manufacturing process is simplified and the manufacturing cost is reduced.

These and other objects of the present application can be resolved entirely by the present application, which is described in detail below.

In one example of this application, the present application relates to a conductive film. The conductive film may include a conductive substrate and a plurality of micelles provided on the conductive substrate to form one layer. The conductive substrate may be an electrode substrate, and the micelle may include conductive particles.

In one example, the conductive substrate may be an electrode comprising a transparent conductive metal oxide. Examples of the transparent conductive metal oxide include ITO (Indium Tin Oxide), In ₂ O ₃ (indium oxide), IGO (indium gallium oxide), FTO (fluoro-doped tin oxide), AZO Gallium 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).

In another example, the conductive substrate may be a metal mesh electrode. Examples of the metal material for forming the metal mesh include metals such as silver, copper, aluminum, magnesium, gold, platinum, tungsten, Molybdenum (Mo), titanium (Ti), nickel (Ni), or alloys thereof may be used.

In another example, the conductive substrate may be an oxide / metal / oxide (OMO) electrode. The OMO (oxide / metal / oxide) electrode may have a metal layer interposed between two metal oxide layers. The metal oxide layer included in the oxide / metal / oxide (OMO) electrode may include, for example, Sb, Ba, Ga, Ge, Hf, In, La, Ma, Se, Si, Ta, Se, Y, Zn, and Zr may be used. The metal layer interposed between the metal oxide layers may contain at least one selected from the group consisting of Ag, Cu, Al, Mg, Au, Pt, , Molybdenum (Mo), titanium (Ti), or nickel (Ni) may be used, but it is not particularly limited.

In one example, the conductive film may comprise a plurality of conductive substrates. In this case, the plurality of micelles may be provided between any two conductive substrates, and a conductive film may be formed such that at least two conductive substrates of the conductive substrates face each other via one layer formed by the plurality of micelles. Depending on the positional relationship with the layer formed by the micelle, the two conductive bases facing each other may be referred to as an upper conductive base or a lower conductive base.

The conductive substrate may be a laminate of any one of the above-mentioned electrode materials and a translucent substrate having a transmittance of about 50% to 90% with respect to visible light. The type of the light-transmitting base material is not particularly limited, and for example, transparent glass or polymer resin can be used as the light-transmitting base material. 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.

The micelle may be defined by an amphipathic compound. Specifically, the micelle may have a form in which heads of amphipathic compounds constituting one micelle are chemically bonded to each other. That is, as mentioned below, the micelles of the present application can be formed from an amphipathic compound comprising a curable functional group in the head, and the head of the amphipathic compound is partially cured and completely cured, Or a cured film, the micelle can be defined as being surrounded by the cured product or the cured film without losing its shape even in the final product.

In one example, the amphiphilic compound forming the micelle may include a curable functional group such as an acrylate group or an epoxy group in the head portion. The kind of the amphipathic compound which can be used is not particularly limited, and a compound suitable for the amphipathic compound may be selected in consideration of the characteristics of the manufacturing method of the present invention mentioned below.

The micelle may form one layer on at least one substrate. In the present application, a layer formed by micelles may be referred to as a micelle layer. The micelles according to the present invention prepared according to the below-described production methods are excellent in morphological stability because they are provided through a partial curing and a complete curing process of an amphipathic compound head, and besides, Only one layer can be formed on the conductive substrate.

The micelle may comprise liquid crystal or conductive particles. In one example, the conductive particles included in the micelle may be charged particles having a (-) or (+) charge. The specific conductive particles are not particularly limited. For example, carbon black, ferric oxides, chromium copper (CrCu), or aniline black may be used as the conductive particles.

In one example, the micelle may further include a driving solvent. The driving solvent allows the liquid crystal or conductive particles to have mobility in an independent phase. Specifically, the driving solvent is a solvent which does not have a curable functional group, and therefore, the mobility of the conductive particles in the final product can be ensured because it is not cured even when the amphipathic compound is cured to the head as mentioned below . The type of the driving solvent is not particularly limited and may be suitably selected in consideration of the production method of the present application mentioned below.

In one example, the conductive film may further comprise a power source. The power source may be configured to apply a suitable level of voltage to the conductive film. The size of the voltage applied by the power source and the electrical connection between the conductive film and the power source can be suitably selected and applied by a person having ordinary skill in the art.

In another example of this application, the present application relates to a method of making a conductive film. The method for producing a conductive film includes forming a micelle formed from an amphipathic compound, curing the interface between the continuous phase and the micelle surrounding the micelle, that is, the head of the amphipathic compound, Particles can be injected. The method of the present invention as described above corrects the dispersion stability of the micelle through partial or complete curing, thereby improving process reliability and durability of the final product.

Specifically, in the manufacturing method of the present application, the head of the micelle (a2) formed from the amphipathic compound (a1) containing a curable functional group in the head is partially cured, and then the liquid crystal or the conductive particles (b) , And completely curing the head of the micelle. Since the micelles have a hardened surface, problems such as micellar destruction due to time lapse, stroke, and the like can be solved.

In one example, the micelle (a2) may be prepared by mixing and / or stirring an amphipathic compound with a hydrophilic or hydrophobic dispersion medium. More specifically, the first composition containing the dispersion medium (c), the initiator (d), and the amphipathic compound (a1) having a curable functional group may be mixed and / or stirred to form the micelle (a2).

In one example, the kind of the dispersion medium (c) usable is not particularly limited and can be selected in consideration of the degree of immiscibility with the driving solvent, as described below. Specifically, the hydrophobicity or hydrophilicity of the dispersion medium is not uniformly determined, and it can be judged in consideration of the polarity of the functional group contained in the dispersion medium and the length of the carbon chain in the compound. In particular, as mentioned below, in relation to the driving solvent (e) to be mixed together, the hydrophilicity or hydrophobicity of the dispersion medium (c) can be relatively determined.

The kind of the initiator is also not particularly limited, and known heat or photoinitiator can be appropriately selected. Preferably, an initiator excellent in miscibility with the dispersion medium can be used.

In one example, the specific kind of the amphipathic compound (a1) can be selected in consideration of the properties of the dispersion medium (c). More specifically, in the present application, since the head of the amphipathic compound (a1) has a curable functional group, when the dispersion medium (c) has hydrophilicity, a curable functional group may be present at the hydrophilic end of the amphipathic compound, (c) is hydrophobic, a curable functional group may be present at the hydrophobic end of the amphipathic compound.

The amphipathic compound may be a compound containing an acrylate group or an epoxy group as a curable functional group. For example, when water or a substance having excellent compatibility or compatibility with water is selected as the dispersion medium (c), examples of the amphipathic compound (a1) having an acrylate group include trimethylpropane triacrylate, trimethylolpropane triacrylate, Propane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene glycol diacrylate, 1 , 6-hexanediol diacrylate or polyethylene glycol diacrylate, and the like can be used.

In one example, the first composition may comprise from 0.01 to 5 parts by weight of initiator (d), and from 0.5 to 25 parts by weight of amphipathic compound (a1) comprising a curable functional group, relative to 100 parts by weight of the dispersion medium (c) .

After the formation of the micelle (a2), the partial curing of the amphiphilic compound (a1) having the curing functional group at the interface between the dispersion medium and the micelle can be performed. The partial curing is a step of maintaining the shape of the micelle and preparing the conductive particles to be introduced into the micelle as described below. In this application, partial curing and full curing of the head of the micelle can be distinguished by whether the micelle is soluble in the dispersion medium and in the insoluble or immiscible solvent. Specifically, when the micelle in which the head is cured is mixed with the dispersion medium which is a continuous phase with respect to the micelle and the insoluble solvent, it can be judged that the head is completely cured when the micelle is not completely dissolved. Conversely, when the micelle melts to some extent, it can be judged that the head is partially hardened.

In one example, the partial curing may be accomplished by either stirring, heat irradiation or light irradiation.

The method of partial curing by stirring is not particularly limited, but can be performed, for example, by stirring at a temperature of 80 DEG C or less for 3 hours or less, preferably 1 hour or less. The partial cure may be achieved through hydrogen bonding between the amphipathic compounds. In this case, the first composition may further comprise water or dimethyl sulfoxide (DMSO).

The partial curing system by heat irradiation is not particularly limited, but can be performed at a temperature of, for example, 80 to 160 ° C, preferably 110 ° C or less. Thermal curing can be applied when the amphipathic compound has an epoxy group.

The partial curing system by light irradiation is not particularly limited, but can be performed by irradiating UV light of 550 mJ / m ² or less, or 500 mJ / m ² or less, for example. Photocuring can be applied when the amphiphilic compound has an acrylate group.

In one example, introduction of the liquid crystal or conductive particles (b) into the micelle can be achieved by mixing two compositions that are immiscible. Specifically, a method for mixing and / or stirring a second composition comprising liquid crystal or conductive particles (b) and a driving solvent (e) which is immiscible with the dispersion medium (c) , Liquid crystal or conductive particles (b) can be introduced into the micelle.

In the case of the conductive particles (b), the constitution or characteristics are the same as those of the conductive particles described above.

In the case of the driving solvent (e) for ensuring the mobility of the liquid crystal or the conductive particles (b) in the micelle, it may be immiscible with the dispersion medium (c) having the curable functional group. The term " immiscible " in the present application can be understood to mean a relative property between the mixed materials, such as that used in a conventional emulsion system or a micelle formation system. For example, in the case of simple mixing of two or more solvents, these solvents may be said to be immiscible if phase separation occurs without mixing with each other. The solvent (e) may be methylene chloride (MC), for example, when the dispersion medium (c) is water or mixed with a hydrophilic solvent such as ethyl acetate without phase separation, , N-hexane, isoparaffin or toluene, and the like. Conversely, when the dispersion medium (c) has a property of being mixed with the hydrophobic solvent without phase separation, a solvent having hydrophilicity may be selected as the driving solvent (e).

In one example, the second composition may comprise 0.1 to 15 parts by weight of the conductive particles (b) relative to 100 parts by weight of the driving solvent (e) which is immiscible with the dispersion medium (c) having the curable functional group .

In one example, 1 to 50 parts by weight of the second composition may be mixed with 100 parts by weight of the first composition. The method for stirring and / or mixing the first and second compositions is not particularly limited and may be performed using, for example, a known homogenizer.

After the liquid crystal or conductive particles are introduced into the micelles, complete curing of the amphiphilic compound (a1) having a curable functional group to the head can be performed. The complete curing is a step of finalizing the shape of the micelle to define the micelle as an independent phase. Since the conductive particles are trapped in the micelles through full curing, they can not be adsorbed to the electrodes even when the conductive particles move according to the voltage polarity. Therefore, the present application can prevent the durability of the product from deteriorating due to the electrode adsorption of the conductive particles.

The method of full curing is not particularly limited, but can be accomplished by stirring for a longer time or by irradiation of stronger heat or light than the condition in which the partial curing is performed, for example. For example, in the case of full curing by stirring, the stirring time may be from 2 hours to 6 hours, or in the case of full curing by heat irradiation, heat of 140 ° C or more may be applied, and in the case of full curing by light irradiation, mJ / m can be achieved by irradiating the UV light for ² to 2500 mJ / m ² range.

After the head of the micelle is completely cured as described above, the method of the present application applies a mixture of the first composition and the second composition onto the lower conductive substrate to form a plurality of completely hardened micelles on the lower conductive substrate The method comprising:

The constitution and characteristics of the conductive substrate are the same as those mentioned above, and the conductive substrate may be referred to as an upper or lower conductive substrate depending on the relative positional relationship with the micelle layer.

In one example, the method of manufacture of the present application is capable of placing the micelle on the underlying conductive substrate, followed by drying. The drying allows the plurality of micelles with the heads to be fully cured to be dense or packed on the conductive substrate to form a single uniform layer. The drying condition is not particularly limited, and may be, for example, stored at a room temperature between 18 ° C and 28 ° C for a certain period of time, or at a temperature of 30 ° C to 100 ° C or under a hot air condition.

In one example, the manufacturing method of the present application may provide another conductive substrate on one side of the micelle layer such that the micelle layer is located between the two conductive substrates. The manner in which the conductive substrate and the micelle layer are bonded is not particularly limited and may be performed using a separate adhesive layer or by a conventional lamination method.

The conductive film may be used for a variable transmittance element or an electronic paper. For example, since the conductive film includes conductive particles that can be moved according to the polarity of a voltage to be applied, or a liquid crystal in which the arrangement is changed, the conductive film may have a predetermined transmittance change or may be formed into a predetermined shape by the movement of the conductive particles. have.

The present application has the effect of simplifying the manufacturing process and reducing the manufacturing cost because the driving liquid including the conductive particles and the liquid crystal can be confined in the cell without forming barrier ribs. In addition, since the manufacturing method of the present application takes the step of partially curing and completely curing the surface of the micelle, it is possible to solve the concern about the long-term dispersion stability of the micelle containing the conductive particles, It is possible to provide one layer formed by densification or packing. Furthermore, since the conductive particles are contained in the micelles, the problem of durability deterioration caused by adsorption of the liquid crystal or conductive particles to the electrodes can be also improved.

1 schematically shows a manufacturing method of the present application.
Fig. 2 is an image of the penetration of conductive particles into the micelle according to the manufacturing method of the present application. Fig.
3 is an image of a conductive film produced according to the manufacturing method of the present application.

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.

Example

Water, TMPTA (trimethylolpropane triacrylate, Sigma-Aldrich), and a hydrophilic initiator (Irgacure 2959) were mixed in a weight ratio of 10: 2: 0.05 to prepare micelles. The micelle-containing composition was irradiated with UV of about 500 mj / m ² to partially cure the micelle surface of TMPTA.

Thereafter, a second composition in which carbon black particles whose surfaces are negatively charged and a hydrophobic solvent (isoparaffin G) are mixed in a ratio (weight) of 0.1: 10 are mixed with the first composition to form carbon black particles And the surface thereof was injected into the partially cured micelles. The penetration of the particle solution into the partially cured micelles was confirmed by a microscope (FIG. 2) while stirring for 2 hours, and the surface of the micelles was completely cured by further irradiating with UV of 2,000 mJ / m ² .

After full curing on the micelle surface, the mixture of the first and second compositions was coated on PET / ITO And dried in an oven at 70 캜 for 10 minutes to form a layer containing a plurality of micelles on the conductive substrate.

Then, a metal mesh was adhered onto the micelle containing layer to prepare a conductive film. The final conductive film is shown in Fig.

Claims (22)

A bottom conductive substrate; And a plurality of micelles provided on the lower conductive substrate to form one layer and containing liquid crystal or conductive particles.
The method of claim 1, wherein the head of the amphipathic compound contained in the micelle is a conductive film
3. The conductive film of claim 2, further comprising an upper conductive substrate disposed to face the lower conductive substrate.
The method of claim 3 wherein the upper and lower 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), IGO (indium galium oxide), FTO (Fluoropod Tin Oxide), AZO (Aluminum Doped Zinc Oxide), GZO (Galium Doped Zinc Oxide), ATO (Antimony Doped Tin Oxide), IZO (Indium Doped Zinc Oxide), NTO (Niobium doped Titanium Oxide) oxide, or CTO (Cesium Tungsten Oxide).
The method of claim 3, wherein the upper and lower conductive substrates are formed of a material selected from the group consisting of Ag, Cu, Al, Mg, Au, Pt, W, ), Titanium (Ti), nickel (Ni), or an alloy thereof.
6. The conductive film of claim 5, wherein the upper and lower conductive substrates are OMO (oxide / metal / oxide) electrodes having a metal layer interposed between two metal oxide layers.
7. The method of claim 6, wherein the metal oxide layer is selected from the group consisting of Sb, Ba, Ga, Ge, Hf, In, La, Ma, Se, Si, Ta, Se, Ti, V, Y, A conductive film comprising at least one metal oxide.
The method of claim 7, wherein the metal layer is formed of a metal selected from the group consisting of Ag, Cu, Al, Mg, Au, Pt, W, Mo, (Ti), and nickel (Ni).
The method of claim 1, wherein the conductive particles are charged particles having a negative (-) or positive (+) charge, and the charged particles include carbon black, ferric oxides, chromium copper (CrCu) Conductive film in black (aniline black).
The conductive film of claim 1, wherein the micelle further comprises a driving solution, and the conductive particles are movable in a micelle.
Curing the head of the micelle (a2) formed from the amphiphilic compound (a1) containing a curable functional group in the head, introducing liquid crystal or conductive particles (b) into the micelle, and completely curing the head of the micelle ;
≪ / RTI >
12. The method of claim 11, wherein the micelle (a2)
A method for producing a conductive film, which comprises preparing a first composition comprising a hydrophilic or hydrophobic dispersion medium (c), an initiator (d), and an amphipathic compound (a1) having a curable functional group.
The composition according to claim 12, wherein the first composition comprises 0.01 to 5 parts by weight of the initiator (d) and 0.5 to 25 parts by weight of the amphipathic compound (a1) having a curable functional group, relative to 100 parts by weight of the hydrophilic or hydrophobic dispersion medium (c) By weight based on the total weight of the conductive film.
12. The method of claim 11, wherein introduction of the conductive particles (b)
A second composition comprising a liquid crystal or conductive particles (b) and a driving solvent (e) immiscible with the hydrophilic or hydrophobic dispersion medium (c) is mixed with the first composition to prepare a conductive film Way.
15. The method of producing a conductive film according to claim 14, wherein the second composition comprises 0.1 to 15 parts by weight of the liquid crystal or conductive particles (b) relative to 100 parts by weight of the driving solvent (e).
15. The method of claim 14, wherein 1 to 50 parts by weight of the second composition is mixed with 100 parts by weight of the first composition.
The method for producing a conductive film according to claim 11, wherein the amphipathic compound (a1) has an acrylate group or an epoxy group as a curable functional group.
18. The method of producing a conductive film according to claim 17, wherein the partial curing is carried out by stirring, heat irradiation or light irradiation.
18. The method of producing a conductive film according to claim 17, wherein the complete curing is performed by stirring, heat irradiation or light irradiation.
15. The method of claim 14, further comprising: after fully curing the head of the micelle, applying the first and second compositions mixed with each other onto the underlying conductive substrate to position the fully hardened micelle on the underlying conductive substrate;
≪ / RTI >
21. The method of producing a conductive film according to claim 20, wherein the micelles are placed on the lower conductive substrate, followed by drying.
21. The method of claim 20, further comprising: providing an upper conductive substrate on a layer of micelles to form a lower conductive substrate opposite the lower conductive substrate;
≪ / RTI >

Images