KR100850874B1 - Manufacturing method of ni nano-particles, ni nano-particles and ink composition comprising the same - Google Patents

Abstract

A method for preparing nickel nanoparticles is provided to suppress the growth of particles through a low-temperature process, to save a cost by omitting a milling process, and to remove environmental pollution factors by using a material having relatively low toxicity and environmental pollution. A method for preparing nickel nanoparticles includes the steps of: preparing a nickel-organic material mixture-containing solution in which a nickel-organic material mixture is dissolved or dispersed in an organic solvent; removing the organic solvent from the solution to obtain nickel nanoparticles having organic impurities; and heat-treating the nickel nanoparticles at a low-temperature atmosphere of 250 °C or below to remove the organic impurities. Further, the step of removing the organic solvent is performed by agitation at room temperature.

Description

Manufacturing Method of Ni Nano-particles, Ni Nano-particles And Ink Composition Comprising The Same}

1 is a schematic view showing a method for manufacturing ultrafine nickel nanoparticles according to an embodiment of the present invention;

2 is an electron micrograph of the nickel nanoparticles prepared in Example 1,

3 is an X-ray diffraction diagram of the nickel nanoparticles prepared in Example 1,

4 is a comparative graph of the X-ray diffraction diagrams of Examples 1-3 and Comparative Examples 1-2.

The present invention relates to a method for producing ultrafine nickel particles, ultrafine nickel particles and a conductive ink comprising the same.

Recently, with the growth of mobile communication devices and the spread of digital TVs, the demand for high quality images is increasing. In order to meet such high quality images, flat panel displays must be accompanied by high definition. In order to meet this, the refinement of related process technologies must be developed. However, when the electrode pattern is formed by conventional screen printing and photolithography, the minimum pattern size that can be printed is determined from the mesh pitch of the screen. Accordingly, pattern formation of 100 μm or less is difficult. In addition, since the number of times of use of the screen needs to be changed to 1000 to 2000 times, and the conductive layer of the unnecessary portion must be removed through etching, the amount of the screen may be used in a larger amount than the required amount, resulting in a material cost increase. The glass frit is also used in the process aspect, so a high temperature process is required and the glass frit has a problem of increasing resistance. Therefore, a study on the inkjet method as a method for forming a fine pattern of 100 ㎛ or less has been made. The inkjet method not only facilitates the formation of a fine pattern, but also draws only the desired pattern, thereby significantly reducing the material cost compared to the conventional photolithography process.

The core material of the inkjet method is a conductive ink, which is composed of conductive nanoparticles containing metal and an ink solvent. Here, the conductive nanoparticles are the core because the surface area of the conductive nanoparticles is much increased compared to the existing bulk particles, and thus, the characteristics can be improved and new properties can be exhibited. In particular, in order to realize an electrode having an appropriate thickness, the content of the nanoparticles in the ink must be increased. As the particles become finer and better in dispersibility, the content of such particles may increase. Accordingly, solutions containing high content of nanoparticles are being developed, and various efforts are being made to develop various applications using the same.

However, despite these advantages, mass production technology has not yet been developed because the particle size and dispersion stability of the nanoparticles are not secured. In other words, the conventional nanopowder manufacturing process is produced by the wet precipitation method using NiCl ₂ , Ni (NO ³ ) ₂ as a raw material, and a large amount of chlorine (Cl) and nitric acid (NO ₃ ) components contained in the raw material The treatment process is very complicated and adversely affects the inkjet process. In order to remove residual elements such as Cl and NO ₃ , a high temperature heat treatment of 400 ° C. or higher is performed at the end of several tens of washings and processes. Powder particles grow in such a high temperature heat treatment process. As a result, it has coarse particle size distribution of 100 nm or more, and the characteristics, reproducibility, and stability as a nano powder may fall. In other words, due to the aggregation of the nanoparticles, the spray uniformity is not secured due to the clogging phenomenon of the nozzle, which causes a performance defect of the final product. Therefore, a low temperature heat treatment and synthesis method for improving the high temperature heat treatment process and improving the particle size and uniformity of the nickel nanopowder are required.

In addition, in consideration of environmental problems, mass production, and the like, there is a need for a method for producing nanoparticles having excellent crystallinity in a simple manner without complicated processes, additives, and the use of hazardous chemicals. When applied as an ink material after remaining in the nanoparticles, it is required to develop a method for producing nickel nanoparticles, which does not have a problem such that the impurities remain in the inkjet wiring to increase the electrical resistance.

The present invention is to solve the above problems,

An object of the present invention is to provide a method for producing ultra-fine nickel nanoparticles by suppressing particle growth through a low temperature process.

Another object of the present invention is to provide a method capable of omitting the grinding step, and to provide a method for producing ultra-fine nickel nanoparticles, which can reduce time and cost.

Another object of the present invention is to provide a method for producing ultra-fine nickel nanoparticles from which environmental pollution factors are eliminated by using materials having relatively low environmental pollution and toxicity.

Another object of the present invention is to provide nickel nanoparticles having an ultrafine particle diameter and specific crystallinity and an ink composition containing the same.

The present invention for achieving the above object,

Preparing a solution containing a nickel-organic mixture in which a nickel (Ni) -organic mixture is dissolved or dispersed in an organic solvent; Removing the organic solvent of the containing solution to obtain nickel nanoparticles in which impurities are present; It provides a method for producing ultra-fine nickel nanoparticles comprising the; heat treatment in a low temperature atmosphere of less than 250 ℃ to remove the impurities organic matter.

In addition, the step of removing the organic solvent provides a method for producing ultra-fine nickel nanoparticles, characterized in that carried out through stirring at room temperature.

In addition, the stirring is performed for more than 8 hours to provide a method for producing ultra-fine nickel nanoparticles, characterized in that to slowly remove the organic solvent.

In addition, the nickel-organic mixture provides a method for producing ultra-fine nickel nanoparticles, characterized in that the form of the chelated (nickel) and organic matter.

In addition, the organic material may include at least one of acetate (acetate), acetylacetonate, oxalate, and acid derived therefrom. to provide.

In addition, the organic solvent provides a method for producing ultra-fine nickel nanoparticles, characterized in that at least one selected from acetone, alcohol having 1 to 4 carbon atoms and glycol.

In addition, the step of removing the organic material by heat treatment provides a method for producing ultra-fine nickel nanoparticles, characterized in that performed in a low temperature atmosphere of less than 200 ℃.

In addition, by performing the step of removing the organic material by the heat treatment provides a method for producing ultra-fine nickel nanoparticles, characterized in that ultrafine nickel nanoparticles having an average particle diameter of 100nm or less is obtained without a grinding process.

In addition, nickel based on the weight of the nickel (Ni) -organic mixture 100 provides a method for producing ultra-fine nickel nanoparticles, characterized in that 15 to 50 parts by weight.

The present invention also provides ultra-fine nickel nanoparticles, which have an average particle diameter of 100 nm or less, as the ultra-fine nickel nanoparticles prepared by the above method.

In addition, it provides an ultra-fine nickel nanoparticles, characterized in that the average particle diameter is 10nm or less.

In addition, it provides an ultra-fine nickel nanoparticles, characterized in that the average particle diameter is 5nm or less.

In addition, the X-ray diffractogram of the ultra-fine nickel nanoparticles shows the largest peak between 2θ and 40-50, the second largest peak between 35-40, and the third largest peak between 60-65. It provides ultra-fine nickel nanoparticles having a crystallinity.

In addition, it provides an ultra-fine nickel nanoparticles, characterized in that the intensity of the noise or impurity peak of the largest peak (Intensity) is less than 1/4.

The present invention also provides an ink composition comprising the ultra-fine nickel nanoparticles.

The present invention also provides a pattern structure prepared by spraying and patterning the ink composition on the substrate by an inkjet method, followed by heat treatment.

Hereinafter, the present invention will be described in detail with reference to the drawings and examples.

The present invention provides a method of preparing a nickel-organic mixture containing liquid in which a nickel (Ni) -organic mixture is dissolved or dispersed in an organic solvent, and obtaining nickel nanoparticles in which an impure organic substance is present by removing the organic solvent. It provides a method for producing ultra-fine nickel nanoparticles comprising the step of removing the impurities organic material by heat treatment in a low temperature atmosphere of less than 250 ℃.

1 is a process schematic diagram of a method for producing ultra-fine nickel nanoparticles according to an embodiment of the present invention.

First, in order to prepare ultra-fine nickel nanoparticles, a nickel-organic mixture containing liquid in which a nickel (Ni) -organic mixture is dissolved or dispersed in an organic solvent is prepared.

The nickel (Ni) -organic mixture is preferably a mixture of nickel and the organic material in the form of chelation (Chelation), not an ionic bond, in particular, the form in which the organic material is wrapped in nickel. This form makes it easy to dissolve or evenly disperse in the organic solvent.

The content of nickel in the nickel (Ni) -organic mixture is not limited, but it is preferable that nickel is contained in an amount of 15 to 50 parts by weight based on the total weight of the mixture. When nickel is included in the range below the nickel, the yield of nickel is not good compared to the mixture, and when nickel is included in the above range, the solubility or dispersibility may be lowered, thereby increasing the particle size of the finally obtained nickel particles.

The organic material may be used without limitation as long as it has a functional group capable of chelation with nickel, preferably acetate, acetylacetonate, oxalate and acid derived therefrom. It is good that at least one of the mixing agent is dissolved in an organic solvent.

The organic solvent may be used without limitation as long as the organic solvent in which the nickel-organic mixture is dissolved or evenly dispersed, and preferably at least one selected from acetone, alcohol having 1 to 4 carbon atoms, and glycol.

Next, the organic solvent is removed from the nickel-organic mixture containing liquid obtained above to obtain nickel nanoparticles in which an impure organic substance is present. When the organic solvent is removed, nickel nanoparticles are gradually precipitated and gelate.

Removing the organic solvent is preferably carried out by stirring at room temperature to obtain the desired nano-sized particles. When the organic solvent is rapidly removed by applying heat, the diameter of the nickel nanoparticles obtained may be somewhat large (however, in the present invention, the removal of the organic solvent is not performed by applying heat). Preferably, the stirring is performed until the organic solvent is sufficiently removed, and preferably, the stirring is performed for at least 8 hours to gradually remove the organic solvent. The upper limit of the stirring time is not limited but is suitable within 96 hours. The stirring may be continuous or may be performed discontinuously and all are included in the present invention.

When the organic solvent is sufficiently removed, ultrafine particles of 100 nm or less are easily obtained without a special grinding process. In this case, when the organic solvent is removed, the organic material that has been cheated with nickel may be removed by evaporation, but a considerable amount remains and remains as impurities.

Next, the organic material remaining as the impurity is heat-treated in a low temperature atmosphere of 250 ° C. or less to remove the impurity organic material to obtain pure ultra-fine nickel nanoparticles. When the heat treatment is performed at a temperature above the above range, the nickel particles are coarse and aggregation between particles occurs, which makes it difficult to obtain desired ultrafine nickel nanoparticles.

In order to obtain ultrafine nickel nanoparticles, it is preferable to heat-treat at a minimum temperature at which the impurity organics can be removed, and in particular, it is preferably performed in a low temperature atmosphere of less than 200 ° C. The lower limit of the heat treatment temperature is not limited, but for the efficiency of the heat treatment effect, heat treatment at a temperature of 150 ° C. or higher, particularly 180 ° C. or higher is preferable.

When performing the step of removing the organic material by the heat treatment, ultrafine nickel nanoparticles are obtained without a special grinding process. That is, in the present invention, ultrafine nickel nanoparticles can be obtained simply without complicated processes such as a reduction step or a grinding step.

The present invention also provides ultra-fine nickel nanoparticles prepared according to the above-described method, wherein the average particle diameter is 100 nm or less, particularly 10 nm or less, and more specifically, the average particle diameter is 5 nm or less. The lower limit of the average particle diameter is not limited, and it is preferable to have the minimum particle diameter as long as the present invention permits. Of course, less than nanosize may not be required depending on the field applied.

In particular, when manufacturing the nickel nanoparticles according to the above-described characteristic manufacturing method, it is possible to obtain nickel nanoparticles having a unique crystallinity. That is, in the X-ray diffractogram of ultrafine nickel nanoparticles, 2θ shows the largest peak between 40-50, the second largest peak appears between 35-40, and the third largest peak appears between 60-65. Ultrafine nickel nanoparticles having crystallinity can be obtained, and in particular, ultrafine nickel nanoparticles having an intensity of noise or impurity peaks of 1/4 or less relative to the intensity of the largest peak can be obtained.

The XRD peak of the ultrafine nickel nanoparticles of the present invention is somewhat different from the bulk peak of the conventional nickel powder. The exact cause of this problem has not been determined, but it is presumed that some ultra-thin organic oxide exists on the surface of the obtained ultra-fine nickel nanoparticles. From the point where the color of the obtained ultrafine nickel nanoparticles is black and the plating test result (the color and the electron microscope confirmed), it was fully proved and confirmed that the component of the obtained powder was nickel.

The present invention also provides an ink composition containing the ultra-fine nickel nanoparticles. The ink composition can be suitably used for the inkjet method. The component of the ink composition is not limited as long as it contains the ultra-fine nickel nanoparticles, and ink compositions known in the art may be applied.

As an example, the ultra-fine nickel nanoparticles and solvents are included, and other additives may be further included. Examples of the additives include, but are not limited to, anti abrasive promoting nano particles and / or flexibility promoting. Flexible promoting polymers and the like. The anti-wear promoting nanoparticles include colloidal and / or fumed silica nanoparticles and / or sol-gel nanoparticles and / or carbon nanoparticles, and the like. And / or functionalized silicone polymers.

Examples of the solvent include, but are not limited to, alcohol organic solvents such as ethanol and ethylene glycol, and may be used in one kind or in mixture.

The present invention also provides a pattern structure prepared by spraying and patterning the ink composition on the substrate by an inkjet method, followed by heat treatment.

When the ink composition is sprayed by an inkjet method to apply the ink composition to a substrate in a predetermined pattern, and then heat treated, a fine conductive pattern structure can be obtained.

In particular, the electrode of the display device can be manufactured by patterning the above method. In the case of using the ink composition, it contains nickel having characteristic crystallinity and ultra-fine nanoparticle diameter, and thus an extremely fine electrode pattern of 100 μm or less can be excellently formed.

Hereinafter, the present invention will be described in more detail. The following examples are examples, so the present invention is not limited thereto.

<Example 1>

10 g of Ni-acetate was added and dissolved in 1 L of acetone to prepare a mixed solution containing Ni-acetate. The prepared liquid mixture was removed by evaporation of the organic solvent and some acetate while stirring at room temperature for 30 hours. After the removal, the obtained dried material was recovered and the impurities were removed by low temperature heat treatment at 190 ° C. for 5 hours in an electric furnace to prepare pure metal Ni nanoparticles.

<Example 2>

Metal Ni nanoparticles were prepared in the same manner as in Example 1 except that the heat treatment temperature was performed at 200 ° C.

<Example 3>

Metal Ni nanoparticles were prepared in the same manner as in Example 1 except that the heat treatment temperature was performed at 250 ° C.

Comparative Example 1

Metal Ni nanoparticles were prepared in the same manner as in Example 1 except that the heat treatment temperature was performed at 350 ° C.

Comparative Example 2

Metal Ni nanoparticles were prepared in the same manner as in Example 1 except that the heat treatment temperature was performed at 400 ° C.

The nickel nanoparticles prepared above were analyzed by particle size with an electron micrograph, and the crystallinity was analyzed by X-ray diffractogram.

2 is an electron micrograph of the nickel nanoparticles prepared in Example 1, and it can be seen that ultrafine nickel nanoparticles having a particle diameter of 5 nm or less are obtained without a special grinding process.

3 is an X-ray diffraction diagram of the nickel nanoparticles prepared in Example 1, where the crystallinity of pure nickel can be seen.

Figure 4 is a comparative graph for the X-ray diffractograms of Examples 1 to 3 and Comparative Examples 1 and 2, it can be seen that the crystallinity of the Comparative Example is poor due to the heat treatment temperature, the best crystallinity is less than 200 ℃ Can be.

The present invention can produce ultra-fine nickel nanoparticles by suppressing particle growth through low temperature process, ultra-fine nickel nanoparticles are obtained even if the grinding step is omitted, time, cost reduction, environmental pollution and toxicity By using this relatively small material, it is possible to eliminate environmental pollution factors, and to provide nickel nanoparticles having an extremely fine particle size and specific crystallinity and an ink composition containing the same, thereby making electrodes of a display device more excellent. Can be.

Claims (16)

Preparing a solution containing a nickel-organic mixture in which a nickel (Ni) -organic mixture is dissolved or dispersed in an organic solvent; Removing the organic solvent of the containing solution to obtain nickel nanoparticles in which impurities are present; Removing the impure organic matter by heat treatment in a low temperature atmosphere of less than 250 ℃; method for producing ultra-fine nickel nanoparticles comprising a. The method of claim 1, wherein the removing of the organic solvent is performed by stirring at room temperature. The method of claim 2, wherein the stirring is performed for at least 8 hours to slowly remove the organic solvent. The method of claim 1, wherein the nickel-organic mixture is in a form in which nickel and an organic compound are chelated. The ultrafine nickel nanoparticles of claim 1, wherein the organic material includes at least one of acetate, acetylacetonate, oxalate, and an acid derived therefrom. Manufacturing method. The method of claim 1, wherein the organic solvent is at least one selected from acetone, an alcohol having 1 to 4 carbon atoms, and a glycol. The method of claim 1, wherein removing the organic material by heat treatment is performed in a low temperature atmosphere of less than 200 ° C. 6. The method of claim 1, wherein the performing of the step of removing the organic material by heat treatment yields ultra-fine nickel nanoparticles having an average particle diameter of 100 nm or less without a pulverization process. The method of claim 1, wherein the nickel (Ni) -organic mixture is included in an amount of 15 to 50 parts by weight of nickel based on 100 parts by weight of the ultrafine nickel nanoparticles. The ultra-fine nickel nanoparticles prepared by the method of any one of claims 1 to 9, the average particle diameter is 100nm or less, the X-ray diffractogram of the ultrafine nickel nanoparticles 2θ is the most between 40-50 Ultrafine nickel nanoparticles, characterized in that the large peak appears, the second largest peak appears between 35-40, and the third largest peak appears between 60-65. The ultrafine nickel nanoparticles according to claim 10, wherein the average particle diameter is 10 nm or less. The ultrafine nickel nanoparticles according to claim 10, wherein the average particle diameter is 5 nm or less. delete The ultrafine nickel nanoparticles of claim 10, wherein the intensity of the largest peak is less than 1/4 of the intensity of noise or an impurity peak. An ink composition comprising the ultrafine nickel nanoparticles of claim 10. The pattern structure prepared by spraying the ink composition of claim 15 on an upper surface of the substrate by an inkjet patterning, and then heat treating the ink composition.

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