KR20150077674A - Nano copper oxide composition for manufacturing metal mesh and manufacturing method of metal mesh using the same - Google Patents

Abstract

The present invention relates to a nano copper oxide ink composition for manufacturing a metal mesh and a manufacturing method of the metal mesh using the same, and more specifically, to a composition which enables to reduce a process time and to reduce process costs as well as minimizing damage of a substrate by a sintering process through a light radiation. According to the present invention, the copper oxide ink composition for manufacturing a metal mesh comprises: a copper particle or a copper precursor having copper oxide and a copper oxide film; and ascorbic acid reducing copper which is oxidized by the light radiation.

Description

TECHNICAL FIELD The present invention relates to a nano-oxide-copper ink composition for forming a metal mesh, and a metal mesh forming method using the same.

The present invention relates to a copper oxide ink composition for forming a metal mesh and a method of forming a metal mesh using the same. More particularly, the present invention relates to a metal ink for forming a metal mesh, which can reduce process take- And more particularly, to a copper oxide ink composition for forming a metal mesh and a metal mesh forming method using the same.

The conductive ink currently used in printing and printing technology is silver ink or silver paste mainly containing silver. In addition, metal particles such as gold, platinum, and palladium may be included in the conductive ink.

Such conductive ink is used mainly as a conductive pattern of a display panel, a solar panel, and a printed circuit board. However, the price of silver contained in the conductive ink is very expensive, and thus it is difficult to realize an economical conductive pattern.

In recent years, techniques for realizing a conductive pattern using a conductive ink having low cost by including copper particles instead of silver particles in a conductive ink have been developed.

However, when a conductive pattern is formed using a conductive ink containing copper particles, an oxide film is easily formed on the surface of each copper particle contained in the conductive ink, thereby increasing the electrical resistance of the conductive pattern.

In order to prevent the copper oxide film from being formed on the surface of each copper particle, it is necessary to perform the firing at an elevated temperature of 500 ° C or higher for 1 hour to 3 hours under an inert gas atmosphere. When firing at a high temperature for a long time in an inert gas atmosphere, There is a problem that the production cost is further increased as compared with the conductive ink using the conductive ink.

Korean Patent Publication No. 10-2012-0060450 Korean Patent Publication No. 10-2013-0031414

An object of the present invention is to provide a copper oxide ink composition for forming a metal mesh, which can reduce process take-time, reduce a process cost, and minimize damage to a substrate by a sintering process through light irradiation.

It is an object of the present invention to provide a metal mesh forming method using the copper oxide ink composition for forming a metal mesh and a metal mesh formed using the metal mesh forming method.

In order to achieve the above object, the present invention provides a copper ink composition for forming a metal mesh comprising copper oxide, copper particles or copper precursor having a copper oxide film, and ascorbic acid for reducing copper oxidized by light irradiation.

The copper ink composition for forming a metal mesh may further include a binder: and a solvent.

The binder may be selected from the group consisting of PVP, PVA, PVC, a cellulose resin, a polyvinyl chloride resin, a copolymer resin, a polyvinyl alcohol resin, a polyvinylpyrrolidone resin, an acrylic resin, a vinyl acetate / acrylate copolymer resin, A resin, an epoxy resin, a phenol resin, a rosin ester resin, a polyester resin, and silicone.

Wherein the solvent is selected from the group consisting of a hydrocarbon solvent, a chlorinated hydrocarbon solvent, a cyclic ether solvent, a ketone solvent, an alcohol, a polyhydric alcohol solvent, an acetate solvent, an ether solvent of a polyhydric alcohol, Or more species.

The solvent is selected from the group consisting of BCA (butyl carbitol acetate), BC (butyl carbitol), texanol, terpineol, BA (butyl acrylate), EA (athylacetate, ethyl acetate) And may include at least one member selected from the group consisting of glycol (EG), diethylene glycol, glycerol, cresol, MEK, and acetone.

The copper precursor may be selected from the group consisting of CuCl, CuCl2, Cu (acac) 2, Cu (hfac) 2, Cu (tfac) Cu (nona-F) 2, Cu (acen) 2, Cu (NO3) 2 and CuSO4.

The particle diameter of the copper oxide, copper particles and copper precursor is preferably 10 nm to 500 nm, more preferably 40 nm to 150 nm.

The amount of the ascorbic acid to be added to 100 parts by weight of the copper oxide, the copper particles and the copper precursor is preferably 0.1 to 5 parts by weight.

The present invention also relates to a process for preparing a copper oxide ink composition comprising copper oxide, copper particles having a copper oxide film or a copper precursor: ascorbic acid, a binder and a solvent; Printing the copper oxide ink composition on a substrate to form a preliminary conductive pattern; And forming a conductive pattern by irradiating light onto the preliminary conductive pattern to reduce and sinter the oxidized copper to form a conductive pattern.

In the copper ink composition, the amount of the ascorbic acid to be added to 100 parts by weight of the copper oxide, the copper particles and the copper precursor is preferably 0.1 to 5 parts by weight.

The substrate may be a synthetic resin substrate selected from polyimide, polyurethane, PMMA and PET, a metal substrate selected from stainless steel, aluminum, gold and silver, or a nonmetal substrate selected from among indium tin oxide and ceramics, have.

The forming of the conductive pattern may include a preliminary light irradiation step for preheating and drying the solvent, and a main light irradiation step for reducing and sintering the copper oxide film to copper.

The printing of the copper ink composition onto the substrate is performed using a printing method selected from the group consisting of ink jet printing, flexographic / gravure ring printing, offset printing, reverse offset, imprinting, .

Wherein the light pulse width is 0.01ms to 100ms, and the pulse gap is 0.1ms to 100ms, the number of pulses is 1 to 1,000 times, the strength is preferably in a 1J / m ² to 100J / m ^2.

The present invention also provides a metal mesh formed using the metal mesh forming method.

According to the copper oxide ink composition for forming a metal mesh of the present invention and the method of forming a metal mesh using the copper oxide ink, the cost of electrode formation can be greatly reduced by using copper oxide or copper oxide formed at low cost.

In addition, by using a light irradiation sintering process, it is possible to minimize the damage of the substrate and reduce the process take-time, thereby further reducing the processing cost.

1 is a flowchart illustrating a process of forming a metal mesh using a copper ink composition according to an embodiment of the present invention.
FIG. 2 is a graph showing the results of resistivity measurement according to light irradiation energy of electrodes printed using the compositions of Example 1 and Comparative Example 1. FIG.

Hereinafter, the present invention will be described in more detail.

In the following description, only parts necessary for understanding embodiments of the present invention will be described, and description of other parts may be omitted within the scope of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely preferred embodiments of the present invention, and are not intended to represent all of the technical ideas of the present invention, so that various equivalents And variations are possible.

First, the copper oxide ink composition for forming a metal mesh of the present invention will be described.

The copper oxide ink composition for forming a metal mesh of the present invention comprises copper oxide, copper particles or copper precursor having a copper oxide film, ascorbic acid, a binder and a solvent.

The copper oxide ink composition for forming a metal mesh of the present invention comprises copper oxide or a copper precursor having copper oxide or copper oxide as a conductor. As the copper raw material, copper oxide or the like can be significantly reduced in production cost by using copper in a partially or entirely oxidized state.

Copper oxide, copper particles having a copper oxide film or a copper precursor preferably have a size of 10 to 500 nm, more preferably 40 to 150 nm. However, the present invention is not limited thereto.

The copper precursor may be selected from the group consisting of CuCl, CuCl2, Cu (acac) 2, Cu (hfac) 2, Cu (tfac) Cu (nona-F) 2, Cu (acen) 2, Cu (NO3) 2 or CuSO4. These may be used alone or in combination. In addition, the copper compounds may be used as such or in a hydrated state.

Ascorbic acid functions as a catalyst in the reaction for reducing copper oxide, copper oxide having a copper oxide film, and copper precursor to copper, and can act as a dispersing agent while reducing the copper raw material such as copper oxide to copper by light irradiation, It also has the effect of preventing re-oxidation. As such, since the ascorbic acid serves as a reducing agent and initiator for the photocomposition, the kind of the binder contained in the ink composition is not limited.

Thus, by incorporating ascorbic acid as a catalyst in a copper oxide ink composition, a synthetic resin substrate selected from polyimide, polyurethane, PMMA and PET, a metal substrate selected from stainless steel, aluminum, gold and silver, A non-metallic substrate selected from glass, silicon, and the like can be used, the adhesion of the conductive pattern to the conductive pattern can be improved, the printing property of the conductive pattern can be improved, and a high aspect ratio can be realized.

In addition, since ascorbic acid is included as a catalyst in a copper oxide ink composition, sintering through light irradiation with a low energy is possible, thereby preventing damage such as xarpage or shrinkage of the substrate, It is possible to reduce the process take-time and reduce the process cost compared to sintering.

It is preferable that the ascorbic acid is added in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the copper oxide, the copper particles and the copper precursor. When the amount of the ascorbic acid added is more than 5 parts by weight, there is a problem of lowering the dispersibility and lowering the homogeneity due to the lowering of the compatibility in the entire composition system. When the amount is less than 0.1 part by weight, the reduction and sintering of smooth copper oxide particles It is not preferable because it is not achieved.

The following binder serves to bind the copper raw material when forming the metal mesh electrode using the copper oxide ink composition, so that the conductive pattern can maintain excellent printability and high aspect ratio.

Examples of the binder include a cellulose resin, a polyvinyl chloride resin, a copolymer resin, a polyvinyl alcohol resin, a polyvinyl pyrrolidone resin, an acrylic resin, a vinyl acetate-acrylate copolymer resin, a butyral resin, an alkyd resin, A resin, a phenol resin, a rosin ester resin, a polyester resin, or silicone can be used. These may be used alone or in combination.

Typically, the solvent may be a hydrocarbon solvent, a chlorinated hydrocarbon solvent, a cyclic ether solvent, a ketone solvent, an alcohol, a polyhydric alcohol solvent, an acetate solvent, an ether solvent of a polyhydric alcohol, or a terpene solvent .

Specifically, the solvent is selected from the group consisting of BCA (butyl carbitol acetate), BC (butyl carbitol), texanol, terpineol, BA (butyl acrylate), EA (athylacetate, ethyl acetate ), Ethylene glycol (EG), diethylene glycol, glycerol, cresol, MEK or acetone.

Next, a method of forming the metal mesh electrode of the present invention will be described.

1 is a flowchart of a method of forming a metal mesh according to an embodiment of the present invention.

1, a copper ink composition comprising a copper raw material, ascorbic acid, a binder and a solvent is prepared (S1).

The copper raw material is used as a conductor, and copper oxide or a copper particle having a copper oxide film or a copper precursor can be used. As the copper raw material, copper oxide or the like can be significantly reduced in production cost by using copper in a partially or entirely oxidized state.

Copper oxide, copper particles having a copper oxide film or a copper precursor preferably have a size of 10 to 500 nm, more preferably 40 to 150 nm. However, the present invention is not limited thereto.

The copper precursor may be selected from the group consisting of CuCl, CuCl2, Cu (acac) 2, Cu (hfac) 2, Cu (tfac) Cu (nona-F) 2, Cu (acen) 2, Cu (NO3) 2 or CuSO4. These may be used alone or in combination. In addition, the copper compounds may be used as such or in a hydrated state.

Ascorbic acid functions as a catalyst in the reaction for reducing copper oxide, copper oxide having a copper oxide film, and a copper precursor to copper, and reduces the copper raw material such as copper oxide to copper by light irradiation.

As a result of the inclusion of ascorbic acid as a catalyst in the copper oxide ink composition, it is possible to perform sintering through light irradiation, thereby preventing damage such as warpage or shrinkage of the substrate, -time can be reduced and the process cost can be reduced.

The binder serves to bind the copper raw material when forming the metal mesh electrode using the copper oxide ink composition, so that the conductive pattern can maintain excellent printability and high aspect ratio.

Examples of the binder include a cellulose resin, a polyvinyl chloride resin, a copolymer resin, a polyvinyl alcohol resin, a polyvinyl pyrrolidone resin, an acrylic resin, a vinyl acetate-acrylate copolymer resin, a butyral resin, an alkyd resin, A resin, a phenol resin, a rosin ester resin, a polyester resin, or silicone can be used. These may be used alone or in combination.

Typically, the solvent may be a hydrocarbon solvent, a chlorinated hydrocarbon solvent, a cyclic ether solvent, a ketone solvent, an alcohol, a polyhydric alcohol solvent, an acetate solvent, an ether solvent of a polyhydric alcohol, or a terpene solvent .

Specifically, the solvent is selected from the group consisting of BCA (butyl carbitol acetate), BC (butyl carbitol), texanol, terpineol, BA (butyl acrylate), EA (athylacetate, ethyl acetate ), Ethylene glycol (EG), diethylene glycol, glycerol, cresol, MEK or acetone.

Once the copper raw material, ascorbic acid, binder and solvent are mixed, additional homogenization and filtering processes may be performed to more evenly mix the constituents.

In the homogenization process, for example, the mixture is linearly dispersed by a linear disperser for 30 minutes to 1 hour, and the linearly dispersed mixture is further dispersed by a three-necked mill. Through such a homogenization process, the constituents of the copper oxide ink composition can be mixed more uniformly. Further, in the filtering step, the foreign substances contained in the copper oxide ink composition are filtered.

Next, the copper oxide ink composition is printed on a substrate to form a preliminary conductive pattern (S2).

Examples of the substrate include a synthetic resin substrate selected from the group consisting of polyimide, polyurethane, PMMA and PET, a metal substrate selected from stainless steel, aluminum, gold, and silver, or a metal substrate selected from among indium tin oxide and ceramics, Substrate and the like can all be used.

Printing on the substrate of the copper ink composition for forming the preliminary conductive pattern may be performed by inkjet printing, flexographic / gravure ring printing, offset printing, reverse offset, imprinting, dispensing printing, or screen printing.

The preliminary conductive pattern may be formed on the substrate, for example, with a thickness of 5 占 퐉, a width of 1 cm, and a length of 2 cm, which are illustrative and thickness, width, and length may be appropriately selected.

Since the preliminary conductive pattern has fluidity before being photo-sintered, it is preferable to dry a part of the solvent included in the preliminary conductive pattern through a drying process after the preliminary conductive pattern is formed on the substrate. The drying process is preferably carried out at a temperature of 70 to 90 DEG C for 3 minutes to 1 hour, but is not limited thereto.

Next, light is irradiated to the preliminary conductive pattern to reduce and sinter the oxidized copper to form a conductive pattern (S3).

In order to form a conductive pattern on the substrate by photo-sintering the preliminary conductive pattern, light is provided to the preliminary conductive pattern formed on the substrate.

For example, a white light generated from a xenon flash lamp may be used as the light to be provided to the preliminary conductive pattern, but it is also possible to use light generated from other types of lamps, It is possible.

The white light generated from the xenon flash lamp can be preferably used because it is easy to precisely control the pulse width, pulse gap, pulse numbers and intensity.

The pulse width of the white light provided to the preliminary conductive pattern may be about 0.01 ms to about 100 ms, the pulse gap generated from the xenon flash lamp is about 0.1 ms to about 100 ms, the number of pulses is 1 to about 100, From about 1 J / cm 2 to about 25 J / cm 2.

If the pulse width of the white light is larger than 100 ms, the incident energy per unit time is reduced and the photo-sintering efficiency may be lowered. Also, if the pulse gap is greater than 100 ms or the number of pulses is greater than 100, copper oxide ink may not be sintered properly due to low energy of white light.

In addition, if the pulse gap is less than 0.1 ms or the intensity of white light is more than 25 J / cm 2, damage or life of the lamp may be shortened and the substrate may be damaged.

In addition, when the intensity of the white light is about 1 J / cm 2 or less, the reduction reaction for reducing copper oxide, copper particles, and copper oxide film formed on the surface of the copper precursor to copper is weak, and the electrical resistance characteristic of the conductive pattern may be deteriorated.

On the contrary, when the intensity of the white light is about 25 J / cm 2 or more, high energy is provided to the substrate, and the substrate may be damaged such as shrinkage, warping and twisting, and the preliminary conductive pattern and the substrate may be peeled off. However, in the case of a substrate having excellent mechanical strength, the intensity of white light can be provided up to about 100 J / cm 2, which is larger than 25 J / cm 2.

The step of providing light to the preliminary conductive pattern to form the conductive pattern can be performed by irradiating the preliminary conductive pattern with light once to the substrate within the pulse width range, the pulse gap range, the pulse number range, and the intensity range of the light described above have.

In addition, light can be sintered by irradiating the preliminary conductive pattern with light twice or more. Preferably, the light is sintered twice to the preliminary conductive pattern to perform photo-sintering of the copper raw material contained in the preliminary conductive pattern . At this time, the primary light irradiation is performed for the preheating of the preliminary conductive pattern, the texture densification and solvent drying, and the secondary light irradiation can be performed for the sintering of the copper raw material.

In order to completely volatilize the solvent in the lower portion (upper portion of the substrate) in the printing electrode, light of 3 J / cm 2 or less is irradiated once or more five times in the pulse width range of 1 to 20 ms at the time of primary light irradiation, And the adhesion between the substrate and the ink can be increased. In the secondary light irradiation, light of 5 J / cm 2 or more can be adjusted in a pulse width range of 5 to 100 ms. The pulse width and the energy can be adjusted according to the type of the substrate and the thickness of the printing electrode. When a polyimide substrate is used as in the following examples, the secondary light irradiation can be performed in a range of 5 to 15 J / cm 2 and a pulse width of 5 to 30 ms. When the light irradiation energy exceeds 15 J / cm 2, deformation such as warping of the substrate occurs due to excessive energy, and even if the same light energy is used, the deformation of the substrate is more serious as the pulse width is larger.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. Such variations and modifications are intended to be within the scope of the appended claims.

Example

Example 1: Preparation of copper oxide ink composition

200 g of copper oxide having an average particle size of 100 nm, 10 g of polyvinylpyrrolidone and 2 g of ascorbic acid were added to 40 g of ethylene glycol, and the mixture was linearly dispersed in a line disperser for 1 hour, To prepare a copper oxide ink composition.

Comparative Example 1: Preparation of copper oxide ink composition

200 g of copper oxide having an average particle size of 100 nm and 10 g of polyvinyl pyrrolidone were added to 40 g of ethylene glycol and mixed. The resulting mixture was linearly dispersed in a linear disperser for 1 hour and dispersed in a three- A composition was prepared. The composition is the same as in Example 1 except for ascorbic acid.

Experimental Example: Formation of Conductive Pattern and Resistivity Measurement

The copper oxide ink compositions prepared in Example 1 and Comparative Example 1 were each screen-printed on a polyimide substrate and then dried at 80 DEG C for 30 minutes to form a preliminary conductive pattern.

Thereafter, the preliminary conductive pattern was irradiated with white light generated from a xenon flash lamp to form a conductive pattern. At this time, the change of the resistivity of the printed electrode was measured while changing the light having the pulse width of 20 ms of white light from 8 to 12 J / cm 2. The results of the resistivity measurement according to the light irradiation energy of the electrodes printed using the compositions of Example 1 and Comparative Example 1 are shown in Table 1 below and the change of the resistivity is shown in the graph of FIG.

Resistivity measurement results according to light irradiation energy Light irradiation energy
(J / cm ² ) Resistivity - Example 1
(u [Omega] cm) Resistivity - Comparative Example 1
(u [Omega] cm) 8 60 125 9 25 75 10 20 50 11 10 70 12 8 80

In the case of the composition of Example 1 in which ascorbic acid was added, the resistivity was constantly decreased as the irradiation energy was increased from 8 J / cm 2 to 12 J / cm 2, while in the case of the composition of Comparative Example 1 in which ascorbic acid was not added, cm < 2 >, and then increased again as the irradiation energy exceeded 10 J / cm < 2 >.

It can be confirmed that the composition of Example 1 exhibits a resistivity lower than 1/2 that of the composition of Comparative Example 1 at all light irradiation energies, so that ascorbic acid aids reduction of the copper oxide layer by light irradiation .

In addition, in the case of the composition 1 of the comparative example, the resistivity was decreased and increased as the light irradiation energy was increased. However, in the case of the composition of Example 1, the resistivity was decreased continuously as the light irradiation energy was increased. It can be confirmed that there is an effect of preventing the re-oxidation of copper.

Claims (16)

Copper oxide, copper particles or copper precursor having a copper oxide film: and
And an ascorbic acid for reducing copper oxidized by light irradiation.
The method according to claim 1,
1. A copper ink composition for forming a metal mesh, comprising: a binder; and a solvent.
The method according to claim 1,
The binder may be selected from the group consisting of PVP, PVA, PVC, a cellulose resin, a polyvinyl chloride resin, a copolymer resin, a polyvinyl alcohol resin, a polyvinylpyrrolidone resin, an acrylic resin, a vinyl acetate / acrylate copolymer resin, The copper ink composition for forming a metal mesh according to claim 1, wherein the composition contains at least one selected from the group consisting of a resin, an epoxy resin, a phenol resin, a rosin ester resin, a polyester resin and silicone.
The method according to claim 1,
Wherein the solvent is selected from the group consisting of a hydrocarbon solvent, a chlorinated hydrocarbon solvent, a cyclic ether solvent, a ketone solvent, an alcohol, a polyhydric alcohol solvent, an acetate solvent, an ether solvent of a polyhydric alcohol, Wherein at least one of the metal particles is at least one selected from the group consisting of copper oxide,
5. The method of claim 4,
The solvent is selected from the group consisting of BCA (butyl carbitol acetate), BC (butyl carbitol), texanol, terpineol, BA (butyl acrylate), EA (athylacetate, ethyl acetate) Wherein the composition contains at least one selected from the group consisting of glycol (EG), diethylene glycol, glycerol, cresol, MEK, and acetone.
The method according to claim 1,
The copper precursor may be selected from the group consisting of CuCl, CuCl2, Cu (acac) 2, Cu (hfac) 2, Cu (tfac) Wherein at least one selected from the group consisting of Cu (nona-F) 2, Cu (acen) 2, Cu (NO3) 2 and CuSO4 is contained.
The method according to claim 1,
Wherein the copper oxide, copper particles and copper precursor have a particle diameter of 10 nm to 500 nm.
8. The method of claim 7,
Wherein the copper oxide, copper particles and copper precursor have a particle diameter of 40 nm to 150 nm.
The method of claim 1,
Wherein the amount of the ascorbic acid added to 100 parts by weight of the copper oxide, the copper particles, and the copper precursor is 0.1 to 5 parts by weight.
Preparing a copper oxide ink composition comprising copper oxide, copper particles having a copper oxide film or copper precursor: ascorbic acid, a binder and a solvent;
Printing the copper oxide ink composition on a substrate to form a preliminary conductive pattern; And
Irradiating light onto the preliminary conductive pattern to reduce and sinter oxidized copper to form a conductive pattern;
≪ / RTI >
11. The method of claim 10,
Wherein the amount of the ascorbic acid added to 100 parts by weight of the copper oxide, the copper particles, and the copper precursor in the copper ink composition is 0.1 to 5 parts by weight.
11. The method of claim 10,
Wherein the substrate is a synthetic resin substrate selected from the group consisting of polyimide, polyurethane, PMMA, and PET, a metal substrate selected from stainless steel, aluminum, gold, and silver, or a nonmetal substrate selected from ceramics, glass, and silicon To form a metal mesh.
11. The method of claim 10,
Wherein forming the conductive pattern comprises:
A preliminary light irradiation step for preheating and drying the solvent, and
And a main light irradiation step for reducing and sintering the copper oxide film with copper.
11. The method of claim 10,
The printing of the copper ink composition onto the substrate is performed using a printing method selected from the group consisting of ink jet printing, flexographic / gravure ring printing, offset printing, reverse offset, imprinting, ≪ / RTI >
11. The method of claim 10,
Wherein the light pulse width is 0.01ms to 100ms, and the pulse gap is 0.1ms to 100ms, the number of pulses is 1 to 1,000 times, the strength is method of forming a metal mesh, characterized in that 1J / m ² to 100J / m ^2.
A metal mesh formed by the method of any one of claims 10 to 15.

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