TW200932405A - Method for producing copper powder, and copper powder - Google Patents

Abstract

A process for producing a copper powder which has a particle size distribution with an extremely narrow width and is reduced in impurity content; and a copper powder which is obtained by the process, has heightened conductivity, is homogeneous, and has high quality. The process for copper powder production comprises: adding a hydrazine-based reducing agent to a copper salt compound slurry obtained by adding an alkali solution to an aqueous copper salt solution to obtain a slurry of cuprous oxide; washing the cuprous-oxide slurry with water and slurrying the oxide again; and adding a hydrazine-based reducing agent again to the resultant slurry of the washed cuprous oxide. In this process, a phosphorus compound is added to the reaction slurry before completion of the final reduction reaction so as to result in a phosphorus/copper molar ratio, P/Cu, in the range of 0.0001-0.003.

Description

200932405 IX. Description of the Invention: [Technical Field] The present invention relates to a method for producing copper powder by a wet method, using a copper salt aqueous solution as a starting liquid and by using a second and a j, and thereby The manufacturer... The copper powder obtained by the cracking & method of the copper powder. [Prior Art] Copper powder is widely used as copper paste or copper

It is a steel powder composed of a micron particle (A m) fine particle 1 melon, and has a structure of a fat component, and is formed by a circuit board circuit which can be applied to a screen. Various types of electrical contact parts, etc., are cured as a conductor film during the sintering process, and exhibit a conductive structure. The influence of miniaturization such as a printed circuit board, conductivity, reliability, etc. by the copper paste-shaped electric power From the point of view, further improvement of copper powder is already in demand in the market. For example, in a microcircuit, when the electrical characteristics are small and the motion affects the product, the conductive filler also has high requirements for electrical stability. Accuracy level. Also, 'because of the fine line of the fine circuit, there is a requirement for the conductive filler of the particle. However, the copper powder is easily aggregated due to the surface of the formed particles = the energy becomes high, which makes the particle size distribution wider and more difficult. In this case, there is a requirement for a uniform particle of copper powder. In addition, when the conductor is formed, since the copper powder particles contain a carbon component, carbonic acid gas is generated during high-temperature sintering, and the conductor is formed. Do not Uniformity hinders the problem of stable conductor formation. Specifically, when a copper powder containing copper powder containing a large amount of carbon is used in a copper paste material, it is formed at a high temperature sintering.

2213-10013-PF 5 200932405 Carbonic acid gas is generated inside the formed film. Therefore, carbonic acid gas is generated, and a crack occurs on the surface of the sintered film, thereby generating internal defects of the conductor. In the above, the steel powder of 匕3 carbon and other impurities is generated in the electric resistance characteristics of the electric resistance value. The change in sputum is required to have copper powder with few impurities and high purity. Patent Document 1 (Japanese Patent Application Laid-Open No. Hei No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No Further, in Patent Document 2, it is disclosed that copper powder having an external phosphorus content of not more than 0.1% by mass to 〇· ι〇 mass percentage and aerobic s amount of G.3G mass percent or less is not used. Cream composition. In the patent document 2 (Japanese Patent Application Laid-Open No. Hei No. 2005-222737), the outer electrode is used for the copper paste composition: the average particle diameter of the spherical copper powder is i micrometer i 4 micrometers 'for the external electrode copper paste The composition is given a $ 丨 shaped drug. Further, in this patent and coating property, the copper powder produced by the organic J document 2 is not particularly limited in terms of the wet reduction method or the dry method.丨 method, etc., and it is better to use water mist but the need for uniform and low-impact copper powder. The information powder of the micro-copper powder produced will contain coarse particles, = = : good dispersion steel to. Also, for...! The impureness of the impurities is such that, in addition to the coarse particles, the classification is enhanced, the yield or the yield is lowered, and the manufacturing cost becomes high. In the case of the copper powder obtained by the conventional wet reduction method, there is a tendency for the particles to be homogenized in the conventional wet reduction method. Therefore, from the viewpoint of reactivity = r, most of them are organic reducing agents ( For example, Patent Document 3;::: Lee

2213-10013-PF 200932405 Application No. 2GG5-314755). As a result, the amount of adsorption of the organic agent in the copper powder tends to increase, and the carbon content tends to increase. Further, in the case of the wet reduction method using an inorganic reducing agent (for example, Patent Document 4; Japanese Patent Application Laid-Open No. 357-591), although the above problem of carbon content is solved, aggregation occurs and the result is obtained. Copper (four) degrees are widely distributed and wide. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the invention is to provide a high-quality copper powder II® having a narrow particle size distribution width, a low impurity content, a high electrical conductivity, and a uniform quality, and a copper powder production method for stably and efficiently obtaining the copper powder. As a result of intensive studies, the present inventors have obtained a copper powder which solves the above problems by the following (four) manufacturing method using the wet reduction method. Copper powder manufacturing method: The copper powder manufacturing method of the present invention is to add a hydrazine-based reducing agent to a copper oxychloride slurry in a copper salt compound slurry obtained by adding a test solution to a copper salt aqueous solution φ, and wash the copper oxychloride slurry by water. In the slurry-washed copper oxide slurry, the copper powder production method m in which the hydrazine-based reducing agent is added again is added to the final reduction reaction, so that the phosphorus-copper molar ratio is P/CU=0.0001 to 0.003. And adding a scaly compound to the reaction mud. Furthermore, in the copper powder producing method of the present invention, the copper concentration of the copper salt compound is preferably from 1 mol/L to 3 m/l. In the method for producing a copper powder of the present invention, the alkali solution is preferably an aqueous ammonia solution.

2213-10013-PF 200932405 In the method for producing copper powder of the present invention, the hydrazine-based reducing agent is subjected to a reduction reaction of from 3.5 to 6.0. The pH value of the copper salt compound slurry added is preferably adjusted.

In the method for producing copper powder of the present invention, it is preferred to adjust the acid value during the reduction reaction of the ammonia hydrazine/liquid mixture into the hydrazine reducing agent in the compound slurry of the former J4. In the method for producing copper powder of the present invention, the acid value of the slurry before the addition of the hydrazine (tetra) original agent in the washed sub-oxidized steel slurry is preferably adjusted to 6.0. The copper powder of the present invention: The copper powder of the present invention is a copper powder obtained by the above method for producing steel powder. The cumulative average particle diameter d5 was measured by a laser diffraction scattering type particle size distribution. 〇 1 姆 s c Λ ^ is ϋ. 1 micro to 5. 0 μm, the standard deviation of the particle size distribution obtained by the laser diffraction scattering particle size distribution measurement and the volume cumulative average particle diameter D5. SD/D5 as shown. It is 0 2 to 0. In addition, the carbon content of the copper powder of the present invention in the air atmosphere at 400 ° C for 30 minutes is preferably not 0.018% by mass. [Effect of the invention] The method can not only eliminate the inclusion of impurities, but also can produce the copper powder having a very narrow particle size distribution width. Moreover, the copper powder of the present invention is obtained by the above-mentioned manufacturing method. [Embodiment] The following is a method for producing copper powder of the present invention and copper powder. The preferred embodiment is described.

2213-10013-PF 200932405 Method for producing steel powder·· First, a process which is a premise of the method for producing a copper powder of the present invention will be briefly described. Initially, a solution of the test solution is added to the copper salt aqueous solution to form a copper salt compound slurry. A hydrazine-based reducing agent is added to the copper salt compound slurry to form a sub-oxidized steel slurry (first reduction treatment). Next, the copper oxychloride slurry is washed with water to obtain a slurry of the copper oxychloride slurry, and the hydrazine-based reducing agent is further added to the copper oxychloride slurry (second reduction treatment). The copper powder to be produced is obtained by the copper powder which has been precipitated by the second reduction treatment. ❺ ❹ : In addition, in the method for producing a copper powder of the present invention, in the above process, until the end of the final reduction reaction, a phosphide having a molar ratio of phosphorus/copper (pWu) of 0.0001 to 0.003 is added to the reaction slurry. in. That is, in the above method, N-quality copper powder having an extremely narrow particle size distribution and low impurity is produced by adding a phosphorus component which is extremely small in copper to suppress precipitation of particles in the process. The juice is made of glutinous powder. First, a copper salt compound is formed with steel by adding a test solution to an aqueous solution of copper salt, thereby preparing a copper salt compound slurry. Example*: Slowly alkali-dissolving in a copper salt solution in 30 minutes; yv Λ* ^ ^ silly standing 3 0 仃..., into, let the alkali solution react with the copper salt to obtain a divalent steel compound. Here, the aqueous copper salt solution is a water-soluble copper salt added to water Q. Sub-dissolved matter temporarily becomes a part of the substance. The water-soluble copper salt is, for example, copper sulfate, cuprous copper, ruthenium sulphide, acetic acid s, etc. Among them, copper sulfate or nitric acid is preferred. The liquid is, for example, ammonia, chlorpyrifos, alkali solution, liquid preparation, potassium oxyhydroxide, sodium ruthenium oxide, and the like. In the case of an aqueous ammonia solution, the use of bismuth can eliminate the impurities and obtain a high purity copper powder.

2213-10013-PF 200932405 Excellent. The copper concentration of the copper salt compound slurry is preferably 丨 尔 / liter to 3 摩尔 / liter. When the copper concentration of the copper salt compound slurry is less than 丨 尔 / liter, the effect of productivity improvement is not obtained. On the other hand, when the copper concentration of the copper salt compound is more than 3 m/l, aggregation occurs, and the control of the particle size distribution is difficult and manufacturing stability is difficult. Further, the copper concentration of the copper salt compound mud is preferably 1.5 mil / liter to 2.5 hr / liter. The alkali solution is only required to be the amount of the copper salt compound which is a neutralized product, and the relationship between the pH values in the subsequent processes needs to be considered. For example, when an aqueous ammonia solution is used as the alkali solution, the amount of the aqueous ammonia solution added is 1.0 mol to 3,8 mol with respect to the copper imol. When the ammonia component is out of this range, there is a problem that control of an appropriate acid detection range becomes difficult in the subsequent reduction t-pass. The copper powder producing method of the present invention preferably adjusts the liquid concentration of the copper salt compound mud copper to a higher concentration. In the conventional wet reduction method, if the copper concentration of the copper cerium salt compound before reduction is high, aggregation of precipitated particles occurs, and it is difficult to efficiently produce copper powder having a narrow particle size distribution width. However, in the method for producing a copper powder of the present invention, the copper salt concentration of the copper salt compound before the reduction reaction is in the above range by various adjustments such as the adjustment range of the pH value and the conditions for the use of the substance, and the particle size distribution width can be obtained. Very narrow copper powder. Next, a hydrazine-based reducing agent was added to the copper salt compound slurry as a copper oxychloride slurry (first reduction). In the method for producing a copper powder of the present invention, the hydrazine-based reduction is adjusted while reducing the copper salt compound to copper oxychloride! The amount is added to make a copper oxide slurry. In other words, the oxidized steel slurry is prepared by the first treatment of the first ^ 2213-10013-pp 200932405, and the reaction at the time of the second reduction treatment is stabilized, whereby the reduced precipitated particles are further uniformized. In the first reduction treatment, the hydrazine-based reducing agent can be used to reduce the possibility of remaining a reducing agent component on the surface of the cuprous oxide particles, and there is no pollutant. The syngas reducing agent is, for example, various substances such as aqueous hydrazine, hydrazine sulfate, and anhydrous hydrazine. Among them, water-containing gas is preferred. Such a hydrazine-based reducing agent may be used singly or in combination. Further, the hydrazine-based reducing agent can be used to react in a solution state because it can rapidly react with %, c & butyl, fused, and homogeneous reactions in the reaction solution. ❿ _ 糸 : : : : : : : : : : : : 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原 原When the amount of the hydrazine-based reducing agent added is less than 0.3 mol with respect to the above-mentioned copper 1 mol, the unreacted copper salt compound may be excessively insufficient. On the other hand, when the addition amount of the hydrazine-based reducing agent is more than 0.5 moles with respect to the above-mentioned copper 1 mole, the reduction reaction may not be stopped in the copper oxide phase. And, in the addition of hydrazine to the steel salt compound slurry, the pH value of the reaction is adjusted to 3 仃', 'f ^ m ^ λ π* . to 6. 〇. The change in the particle size of the cuprous oxide particles obtained by the pH value of the solution in the upper bismuth increases, and the particle size distribution width of the copper powder particles in the final production time becomes wider. From the copper salt compound slurry, in addition to the addition of the hydrazine-based reducing agent, it is preferred to adjust the acid-base value of the aqueous ammonia solution of the agent to adjust the pH value, and use it as the acid value adjustment = Treatment. The ammonia solution of the former I value adjustment agent can also be used in copper salt.

2213-I0013-PF 11 200932405 When the compound slurry is formed, it is neutralized with ammonia as the test solution. Since the substance is the same, the use of the different components can be excluded as much as possible, and the residual impurities are eliminated as much as possible. As a result, the purity control of the obtained copper powder can be easily performed. ❾ ❹ In the above first reduction treatment, in the process of adding copper to the copper salt compound u, it is preferred to use a hydrazine-based reducing agent=U Moir to 0.5 Mohr, ammonia. The aqueous solution (as a ratio of illusion to 〇2, to 0.4 mil is continuously added. The pH value of the reaction sludge added as described above is adjusted to the initial acid value at the start of the addition of the reducing agent and the pH adjuster. When the beam is reduced (4), the acidity of the acid is (10). r Here, the copper oxide slurry means a clay containing copper oxychloride, or may be a component other than copper oxychloride. The same is true for the copper mud. Also, if the pH value of the obtained copper oxychloride slurry is in the range of 35 to 6.0, then in the subsequent process, the acid value of the reaction slurry is changed within the preferred range. This result shows that the particle size of the obtained copper powder can be made uniform. When the acidity of the copper oxide mud is more than the U side, the copper: the copper component does not stop at the copper oxide. Agglomerated to form gold in another aspect, 'oxygenated copper mud slurry is more than 3.5. The reduction may be incomplete, and the manufacturing efficiency is lowered. Further, the temperature of the reaction mud in the first reduction treatment is preferably in the range of 40 degrees Celsius to 6 degrees Celsius. When the reaction mud temperature is less than Celsius, the reduction reaction speed is higher. Slowly can not meet the industrial productivity. · Another 2231-10013-pp 12 200932405 Although the reaction mud temperature exceeds 60 degrees Celsius, the reduction rate is too fast, causing a heterogeneous reduction reaction, resulting in the obtained copper powder powder Next, the copper oxychloride slurry is washed with water, and then mudted to clean the oxynitride and copper/b 襞. First, the copper oxychloride slurry is allowed to stand, and the copper sulphide particles are obtained in the slab. After the precipitation of the copper oxychloride particles, the upper portion is removed. The liquid is cleaned by adding water to clean the copper oxide particles to become a washed copper oxide slurry. The acid phase of the copper oxide slurry is 41 to 6 〇, and in the subsequent process, the acid and alkali are added. When the value fluctuation is suppressed within an appropriate range, the particle diameter of the obtained copper powder W can be made more precise. Further, the method for washing the cuprous copper particles is not particularly limited, and a known washing can be employed. However, the use of the exclusion washing described below can better manage the pH value of the copper oxide slurry in the washing to the washing level. The repelling washing is the precipitation of the copper oxide on the exhaust gas, and then injecting Wash the water and carry out the above operations several times. Further, it is preferable to wash the washing water and make the pH value of the washed copper oxide mud to be any value within the range of 41 to 6 〇❹. Acidity and alkalinity, and repeated washing. When the acidity and alkalinity of the washed copper oxide mud is more than the acidic side of 4.1, the reduction efficiency will be worse. On the other hand, the acidity and alkalinity ratio of the washed copper oxide slurry is higher than that. 6. When the ruthenium is still on the alkaline side, when the reducing agent for obtaining the copper powder is added, the powder characteristics such as an increase in the reaction change and a decrease in the dispersion property may be deteriorated. Further, it is preferable to wash the powder. The pH of the cuprous oxide mud is washed at a pH of any of the range of 4.3 to 4.7. The stability is best achieved by washing the copper oxide mud to a pH within the above range. In the washed copper oxychloride slurry obtained by the enthalpy preparation, hydrazine 2231-10013-PF 13 200932405-based reducing agent 'reduction-precipitated copper powder is added (the second reduction washing and drying of the precipitated particles, that is, obtaining copper powder, The amount of filtration, in addition to the addition of aunt + + plus hydrazine-based reducing agent 篁 添加 at the end of the addition, compared to the cleaning is preferably added 0.3 碍 $ 7 ζ h steel containing copper 1 Mohr, salinization The character spray (4) ratio ° also has the ratio of the sum of the hydrazine-based reducing agent added to copper relative to the copper i ^ 匕 copper mud. The 为 is 0.6 摩尔 to 2.0 莫 藉 联 amp amp & The addition of the stupid reducing agent, the imminent acid value is preferably adjusted to 4 > the mud of the reduction reaction to the range of 6. 还. The ratio of the base of the reaction is also 4. 1 also acid copper # H The acid in the reaction of the banquet is on the one hand, the eyebrow is on the one hand, and the 5A is the same, and the coarseness is increased by 3, and the dispersibility is deteriorated. On the other hand, the acidity and alkalinity of the reduction reaction is more than 6 · 0, and the number of particles of the precipitated particles is excessive. More than, k 'reducing agent is the same as adding hydrazine-based reducing agent (second place) to the bismuth copper salt compound loach 'Addition of the Dunton-based reducing agent (the second reduction treatment) ij of the washed copper oxide mud copper concentrate " / rose to Wii / 4, Γ is adjusted according to the amount of liquid into 1 Moer G _,, to wait To the copper powder with a narrow particle size distribution. Further, the copper excitation is preferably u Mohr / rise to 25 m / liter. Also, the temperature of the hydrazine reductant is preferably maintained at 40 degrees Celsius. A certain temperature range of 60 ° C. When the temperature of the bismuth hydride reducing agent is lower than 40 degrees Celsius, the reduction reaction will be pure, and it will not meet the industrially desirable productivity. , Department => When the temperature of the milk-based reducing agent is higher than 60 degrees Celsius, the reduction reaction will be earlier and the particle size will not be obtained. The reducing agent used in the first reduction treatment and the second reduction treatment will be treated with the same kind of hydrazine. Reductant, as a reducing agent, the reducing ability of hydrazine as a reducing agent is

2213-10013-PF 200932405 Get a good copper powder with good character. Even the heterogeneous 'knife used for copper powder reduction can be limited to a small amount to suppress the incorporation of impurities into the surface of the copper powder particles. In the state of the reaction slurry at the end of the second reduction treatment, the fluid mill method (such as a fine-rolling mill) or a laminar flow mixing method (TKFUmics) may be used to centrifuge the fluid slurry at a high speed. The particles collide with each other and smash, close to the primary particles, and at the same time apply the granule treatment for smoothing the surface of the particles, thereby further improving the particle dispersibility. Addition of phosphorus compound: The method for producing a copper powder of the present invention is to add a phosphorus compound to the molar reduction of the scale and copper by the molar ratio P/Cu 0.0001 i 〇〇〇3 in the above-mentioned production method to the final reduction reaction. In the reaction mud. By adding a phosphorus compound, the scale compound acts as a steric hindrance to prevent the precipitation of the precipitated particles from being long and monodisperse. As a result, the obtained copper powder particle size distribution can be greatly narrowed. The phosphorus compound is obtained by reacting phosphorus and copper Mohr ratio p/Cu=o. 0001 ❹: in the reaction slurry. The method of 2,003 is added in a very small amount. In order to suppress the content of impurities, high-purity copper powder is obtained, so that the amount and type of the added substances must be suppressed as much as possible in the manufacturing process. However, the addition of a phosphorus compound is effective for the purpose of micronizing and not agglomerating to obtain fine particles of fine particles having a narrow particle size distribution. As a result of intensive investigation of the amount of scaly compound added by the inventors, it has been considered that the addition of the above-mentioned specific phosphorus compound is most effective. Here, Fig. 1 is a graph showing the correlation between the phosphorus compound addition ratio and the particle size distribution width. In the graph of the i-th graph, the horizontal axis is the display disc compound.

2213-10013-PF 15 200932405 Adding ratio of phosphorus/copper, the value of the width of the particle size distribution of the copper powder shown on the vertical axis is the volume cumulative average particle diameter Ds (i and the measurement by the laser diffraction scattering particle size distribution) The SD/D5 obtained from the standard deviation of the particle size distribution measured by the method S1). Value.

❹ Here, the standard deviation SD is an index β indicating the change in the whole-grain pinch data obtained by the laser diffraction scattering type particle size distribution measurement method, and the larger the value, the larger the change. Also, the standard deviation SD and the volume cumulative average particle diameter Ds. The ratio between SD/D5. It is the degree of the width of the particle size distribution. The larger the value, the wider the width of the particle size distribution. It can be seen from Fig. 1 that in the case where phosphorus is not added (phosphorus/copper two to a phosphorus addition amount less than phosphorus/copper = 0.0001, the SD/L value is greater than 0.55, by phosphorus The effect of monodispersion may be incomplete. For this reason, the ratio of phosphorus addition to phosphorus/copper = 0.0001 or more 'SD/Ds. The value can be significantly reduced. There is also added more than the upper limit of the invention phosphorus / copper = 〇〇〇 3 When the amount of phosphorus is small, the value of SD/D5 is not observed. The reason is that the present invention is aimed at suppressing the content of impurities to obtain high-purity copper powder, so that the amount of phosphorus added is suppressed to a minimum. Copper = 〇. During the addition period of the dish compound, the dish compound of the above ratio may be added in any stage until the end of the reduction reaction by adding the hydrazine-based reducing agent to the washed copper oxide slurry, especially in the preparation of the washing. The copper oxide mud is added after the polymerization, because the amount of the phosphorus compound can be suppressed in a small amount after the washing, thereby suppressing the impurity content. The lining compound is preferably used to efficiently disperse the scale component in the water in the reaction mud. Phosphorus compound. Water-soluble phosphating Was read using a preferred

2213-10013-PF 16 200932405 Any of sodium, phosphoric acid, ammonium hypophosphite, and the like. In particular, it is more suitable for the precipitation of particles and uniform particle size. - Human ammonium phosphite The copper powder obtained above is subjected to hydrazine, washing, drying, etc. to be converted into copper powder. Also, the copper powder, Cheng, 祛34^: ~ liter oxidation resistance, better than the application of organic surface treatment. The surface treatment agent preferably includes any of a fatty acid or an amine of hydrazine, and specifically, a fatty acid such as oleic acid or sulphate or an amine such as octadecylamine or oleylamine is required. Acid acid, ❹ ❹ With the corresponding classification device, mixer, ‘classifier, etc., the particles can be collided with each other to improve particle dispersibility. The apparatus for carrying out the granules 1 The steel powder of the present invention: The copper powder of the present invention is a copper powder obtained by the above steel powder. Further, the volumetric cumulative average particle diameter D5e transmitted by the scattering type particle size distribution measurement method is the same as that of the stomach method. The Wei value of the width of the width of the i micrometer to 2 distribution is ....5 Table 2: Using the above copper powder manufacturing method, the copper powder of D"=〇y' inch can be made into the aforementioned SD/Ds. The value is 〇. U. The narrower width of the micron rule cloth. The particle size of the steel powder of the present invention is less than 01, and the agglomeration is generated. This xiao m 1 is accompanied by micronization and the amount m is necessary to increase the compounding circuit for suppressing the agglutination potential. The conductivity does not cause, the fine circuit forms a low impurity level of the poor conductivity of the rabbit road. It is 0.5 micrometer to 3.5 micrometers. Also, preferably, on average, in the general case, the particles. Agglutination

22J3-J0013-PF 17 200932405 Because there is D 5. It is 2- i 2--. — .i micro-particle size not in the range of 5 〇 micron particles, but the SD/D5() particle size is very narrow and sharp. The degree of the particle size distribution width of the copper powder is not shown by the above method SD/Ds°. Further, when the SD/D50 value is in the range of 〇.2 to 〇.5, the aggregation is less. When the SD/D5fl value exceeds 〇. 5, the particles change more and are not suitable for the formation of fine lines. Further, the steel powder of the present invention has a carbon content of less than 质量1 mass% after heat treatment at 4 ° C for 3 Torr in an atmospheric atmosphere, and the carbon content is extremely low. The copper powder of the present invention is treated with an organic surface which is useful for preventing oxidation, and the surface treatment agent disappears from the surface of the copper powder at a temperature of from 200 ° C to about 300 ° C. Therefore, the copper powder after sintering at 400 ° C for 30 minutes is in a state where the surface treatment agent has been removed, and the carbon content of the copper powder measured in this state can be presumed to be formed by sintering to form a copper crucible at a temperature of the conductor film. Carbon content. In addition, the carbon powder content of the copper powder referred to in the present specification is measured by using a carbon analyzer (EMIA_32〇v manufactured by Horiba Manufacturing Co., Ltd.). When the copper powder of the present invention is used in a copper paste or the like, when the copper paste is sintered, the surface treatment agent disappears before the sintering start temperature of the conductor surface, so that after the sintered formed film is formed on the surface of the copper body, carbonation does not occur inside the conductor. The gas, in turn, prevents the surface of the conductor from bursting to form a high quality conductor. Hereinafter, the present invention will be specifically described by way of examples and comparative abilities. The present invention is not limited to the following embodiments. Further, in order to compare the copper powder production conditions in the following Examples and Comparative Example 2, a summary of the production conditions is shown in Table 1. 2213-10013-pp 18 200932405 Table 1 Example 1 Example 2 Comparative Example 2 Copper salt aqueous solution pure water 6.5 6.5 6.5 Copper sulfate gram 6000 6000 6000 Copper compound mud to prepare ammonia aqueous solution. 25 weight percent concentration ml 2537 2537 2537 liquid temperature Celsius 50 50 50 Add time minute 30 30 30 1st reduced copper concentration Mohr / liter 2 2 2 Reducing agent gram 450 450 450 Acid test adjuster ml 591 591 590 Add time minute 30 30 30 Liquid temperature Celsius 45 50 50 Wash Net copper oxide mud modulating copper concentration Mohr / liter 2 2 2 Liquid temperature Celsius 45 45 45 Acid value after washing 4.7 4.7 4.7 2nd reduction copper concentration Mohr / liter 2 2 2 Reducing agent 1200 1200 1200 Add time Minute 30 30 30 Liquid temperature Celsius 45 45 45 璘 Compound added compound ammonium hypophosphite trisodium phosphate 12 water and no added amount of grams 3. 02 11.06 Addition period added to the washed copper oxide slurry added to the copper sulfate aqueous solution Note: Reducing agent: hydrazine 1 water and pH adjuster: 25 weight percent aqueous ammonia solution [Example 1] First, in pure water 6000 g of copper sulfate was added in 6.5 liters and stirred. Thereafter, the liquid temperature was maintained at 50 ° C, and further water was added to adjust the concentration of the copper sulfate aqueous solution (copper brine solution) to 9 liters. 3 〇 tapping in the aforementioned 2213-10013-PF 19 200932405 copper sulfate aqueous solution! i > Add ammonia solution (concentration 25 parts by weight) to 2537 ml of the bell, and simmer it into <> Also, it is difficult to hold the copper salt compound mud for eight μ^7 knives to make it ripe. At this point, the copper salt compound mud liquid temperature is maintained at a temperature; $ ς η & 45 production, 50 degrees Celsius, after the ripening, the liquid temperature is adjusted to Celsius ❹ Next, water is added to make the copper salt compound mud copper concentration 2 〇 Moore /L' and adjust the amount of liquid. The copper salt compound slurry is maintained at a pH of 6.3, and the liquid temperature is 5 degrees Celsius. At this time, the continuous addition of hydrazine 1 water and the compound (the reducing agent) in the % minute is similar. 591 ml of an aqueous ammonia solution (concentration: 25 weight percent) as an acid tester was added to be a copper oxide mud (first reduction treatment). Further, in order to completely carry out the reduction reaction, the stirring was further continued for 3 minutes. After that, in order to repel the washing, pure water was added to the copper oxychloride slurry, and the amount of the liquid was adjusted to 18 liters, and then the copper oxide particles were allowed to stand still after being placed, and then the operation was carried out after standing and standing for 14 liters of liquid. The above-mentioned action was repeated until the acid value was 4.7. Also, add 8 liters of warm water to make the total liquid volume μ μL, maintain the liquid temperature at 45 ° C, and adjust the copper concentration to 2 〇 Mohr / liter as the washed copper oxide mud. In the washed copper oxide mud after the adjustment of the copper concentration, 3.02 g of sub-hypo-alloy was added, and the mixture was stirred for 5 minutes (phosphor compound addition process). Add water to make the copper concentration of the washed copper oxide mud 2 〇 Mohr / liter, and adjust the liquid volume. In this case, the copper oxychloride slurry is washed, and a combined water and a substance (a hydrazine-based reducing agent) 丨 2 〇〇 are added in a minute. . Anyone, further mixing for 15 minutes' complete reduction reaction to reduce precipitation of steel powder (2nd also

2213-10013-PF 20 200932405 Original processing). ^; Consider and take out the precipitated copper particles. In addition, after the washing, the copper was added to a cold solution of 15 g of a methanol solution of 15 g of a solution of 15 g of an organic surface treatment. After filtration, the mixture was heated and dried at 70 ° C for 5 hours, and further pulverized. Processing to obtain copper powder. The copper powder obtained in Example 1 was subjected to ', Ds. , "ββτ specific surface area, plug packing density, carbon content, etc.. Further, the specific surface area I is calculated based on the BET specific surface area of the obtained copper powder, and the organic surface-treated copper powder obtained by measuring Example ι is in the atmosphere. The carbon content after sintering in the atmosphere at 4 degrees Celsius for 30 minutes. The results are shown in Table 2. Further, the particle size volume reference map is shown in Fig. 2, and the bronzing electron microscope (SEM) image is shown in Fig. 3. The individual measurement methods are shown below.

Volume cumulative average particle diameter I obtained by laser diffraction scattering particle size distribution measurement method: Copper powder was mixed with H aqueous solution (manufactured by Sannopco Co., Ltd.) of SN dispersant 5468, and homogenized in ultrasonic wave ( After 5 minutes of dispersion under the Nippon Seiki Co., Ltd. t US-300T), a laser diffraction scattering particle size distribution measuring device Micr〇Trac HRA 932()_χι(10) (Leeds + Northrup) was used at a flow rate of 5 〇 cubic meters. Measurements are taken in centimeters per minute. The measured volume cumulative measured particle size is Ds. And measuring the volume cumulative 10% and 9〇% of the particle size in the same way as Dh, L. . Plug packing density (TD) · Use powder body _ρτ_Ε ( H〇s〇kawa

Measurements were made by Micron Co., Ltd.). Specific surface area: 1 00 gram for 1 〇 at 75 ° C. After degassing, use m_sor (Quantachr〇ine Gongsaki earns)

2213-10013-PF 21 200932405 Co., Ltd.) The measurement was performed by the BET1 point method. Further, the specific surface area DBET is assuming that the obtained copper powder is a true spherical shape, and the specific surface area SSA and the copper true specific gravity measured by the BEn point method are 8.92, and are calculated using DBET == 6/( 8 92 xSSA). Carbon content: The carbon content after holding for 3 minutes at 400 ° C was measured using a carbon analyzer (emu_32〇v manufactured by Horiba Manufacturing Co., Ltd.). [Example 2]

Example 2 is an example in which the phosphorus compound addition period differs as compared with Example 1. That is, instead of adding ammonium hypophosphite to the washed copper oxide slurry, the liquid temperature of the aqueous solution of the sulfuric acid steel is maintained at 5 G Celsius, except that the addition of trisodium phosphate 12 water and U shoulder as a filling compound is added. Copper powder was obtained in the same manner as in Example i. Regarding the steel powder obtained in Example 2, it was measured 1 and the example i = data. The results are shown in Table 2. Also, the particle size volume reference distribution is shown. Electron microscopy (SEM) image as shown in Fig. 5 L Comparative Example 1] Comparative Example 1 is an example in which an organic hydrazine reducing agent was used in the production of copper powder by the method of thirst. First, add copper sulfate 5 water and a copper salt solution of the material in ^ Q Q ± , 幵 at 60 ° C pure water q. Also, the degree becomes 2 Mo. In addition, pure water is added to the brine solution to make the copper concentrate 2213-10013-pf 22 200932405. Next, the liquid temperature of the copper salt aqueous solution is maintained in a 25% aqueous solution of sodium hydroxide, 46 〇 & degree, sequentially added, U-transferred steel salt Compound mud. The receiver will add the copper salt compound to the mud, and add the water to the water. ^^ Hold at 50 degrees Celsius, in the eight shovel, ★ into, gram. Further continue to stir the 60-knife clock to reduce the precipitation of steel powder. The copper powder obtained as described above was filtered and taken. Also, the solution has octadecylamine 1.5 g tfg! # n handle, ... 5 liters of the application of the organic surface at the point of stirring 30 7 knives, and 80 degrees Celsius, 5 hours of teaching age to get Powder. Regarding the obtained copper powder k ... 钇屎 q Zhong Na's uncharacteristics are measured by the same data. The result is that the granule knives are sharp, but the carbon content after sintering at 400 ° 30 minutes is 〇〇 7 weight percent. [Comparative Example 2] In Comparative Example 2, a scaly compound was added to the production of steel powder by the thirst-trapping, ‘,', and A reduction methods. That is, the ha-a is not the same as the addition of the phosphorus compound, and the same method as in the first embodiment is used to hunt the 丨丨, ^, 击, and bake to the copper powder. Regarding the characteristics of the obtained steel powder powder, the data of the phase η μ I w ^ 1J 与 of the first embodiment was measured and calculated. The results are shown in Table 2. And 'Comparative example? The volume reference particle size distribution of the copper powder obtained in Example 2 was as shown in Fig. 6. [Comparative Example 3]. Comparative Example 3 uses the method disclosed in Patent Document A _ 』Document 4, which is an example in which the concentration of the copper-containing solution is the same as that of the steel salt of the first embodiment. First, mixed human copper sulfate pentahydrate and 395 grams and bell fire n fβ σ "when water is 0.05 liters, and further add sodium coke sodium 40 grams" to make a copper-containing solution. In the solution, add "Chenqi water (dispatch 28%). Ancient and Japanese people make 1 0" 500 grams, and mix and produce copper ammonia wrong ions.

22] 3^] 〇〇i3-PF 23 200932405 solution. Pure water was added to the copper ammonia mision solution until the total liquid amount was 〇, liter, to the same copper concentration as in Example 1. In the copper ammonia counterion solution, after adding and mixing 200 g of saturated water hydrazine as a reducing agent at a temperature of 30 ° C, the liquid temperature is raised to 8 ° C and maintained for 2 hours until the reaction is completed completely. . Thereafter, the copper powder obtained as a metal steel was recovered and washed from the solution. Further, in the above-described process, in Comparative Example 3, sodium pyrophosphate having a phosphorus compound was added during the preparation of the copper-containing solution, and then a reduction reaction was carried out. The obtained copper powder powder characteristics were measured and the same data as in the examples were obtained. The results are shown in Table 2. Further, the volume-based particle size distribution map of the copper powder obtained in Comparative Example 3 is shown in Fig. 7, and the bronzing electron microscope (SEM) image is shown in Fig. 8.

Clothing Z

^----~~~ L 99 98 * Carbon with a pair. The copper powder obtained in the examples is compared with the steel powder obtained in the comparative example.

2213-10013-PF 24 200932405 First, in the embodiment, see the particle size volume reference distribution of Fig. 2 for details. The particle size of 1 μm is a frequency peak, indicating that the particle size distribution width is narrowly and sharply distributed. The values of SD/D^, D9fl/I)l() of this embodiment are all significantly lower. The plug packing density (TD) is also a low value. It was further found that the yield was a high value of 96%. Under atmospheric atmosphere, at 40 ° C for 30 minutes, the carbon content after sintering is already below the amount of 0.01 weight percent that the measuring device may detect, and is less than 重量 1 weight percent. Further, in Example 1, compared with Example 2 and Comparative Example 1, it was found that the carbon contents of Examples 1 and 2 were less than i. 0i by weight, whereas Comparative Example 1 was 〇· 07. Weight percentage, more carbon content. The copper powder of Comparative Example 1 using an organic reducing agent was also larger than the above-mentioned copper powder carbon content of the present invention. Such a copper powder having a carbon content is difficult to obtain as a particle of the present invention, and the conductor is stably formed to improve conductivity. Next, in Example 2, in comparison with Comparative Example 2, the average particle diameter and even the carbon content were equivalent. However, the embodiment is significantly lower, to SD/D5. It can be found that there is a significant difference of about 30%, and it is understood that the width distribution of the embodiment is narrow. The copper powder obtained in Comparative Example 3 is shown in Fig. 7 as a scanning electron microscope (SEM) image of copper powder. Most will produce agglutination. Further, the average particle diameter of the primary particles obtained by the analysis of the scanning electron microscope (SEM) image shown in Fig. 7 was about 2 μm, but excessive aggregation was observed, and as a result, Dsf was about 34.68 μm. Also, SD/Dse is low, but as explained above, the size of the collected particles is much larger than that of the embodiment, and it is difficult to call

2213-10013-PF 25 200932405 乍 is the particle size distribution of the particulate copper powder. Therefore, you are included in the report that you have a lot of coarse grains and are not suitable for the fine lines. Yuan Cheng. Also, the yield was significantly worse than the examples. That is, in the method of Comparative Example 3, it was difficult to produce a fine particle copper powder having a sharp particle size distribution in a high yield in this particle size distribution. [Industrial Applicability] The copper powder producing method of the present invention can homogenize particles to produce copper powder having less impurities than conventional products. Further, the obtained copper powder is used as a material for forming a conductor by a screen printing method, and it is possible to prevent formation of fine lines and to form a conductor having excellent electrical stability. Therefore, the copper powder of the present invention is suitable as a material for forming fine lines. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a graph showing the relationship between the amount of phosphorus compound added and the particle size distribution width in the method for producing copper powder of the present invention. Fig. 2 is a graph showing the particle size distribution of the copper powder obtained in Example 1. 〇 Fig. 3 is an SEM image showing the copper powder obtained in Example 1. Fig. 4 is a graph showing the particle size distribution of the copper powder obtained in Example 2. Fig. 5 is a sem diagram showing the copper powder obtained in the second embodiment. Fig. 6 is a graph showing the particle size volume reference distribution of the copper powder obtained in Comparative Example 2. Fig. 7 is a graph showing the particle size distribution of the steel powder obtained in Comparative Example 3. Fig. 〇 * 22m〇〇i3: PF 26 200932405 Fig. 8 shows the SEM of the copper powder obtained in Comparative Example 3 [Explanation of main component symbols]

27

2213-10013-PF

Claims (1)

200932405 X. Applying for a patent garden: 1. A copper powder manufacturing method, in which a copper salt compound slurry obtained by adding a test solution to a copper gentleman ~ j water/cold solution is added, and a hydrazine-based reducing agent is added. The copper oxychloride slurry is washed with water and the oxidized steel slurry is washed, and the hydrazine-based reducing agent is added again in the mud slurry to be washed, and the hydrazine-based reducing agent is added again, and the characteristics are as follows: With copper Moby P/Cu = 0.0001 to ° .003' and a dish compound was added to the reaction mud. 2. The method for producing a copper powder according to the above aspect of the invention, wherein the copper salt compound has a copper concentration of from 1 mol/liter (10)/L to 3 m/l. 3. The method for producing a copper powder according to claim 1, wherein the test solution comprises an aqueous ammonia solution. 8. The method for producing a copper powder according to the first aspect of the invention, wherein the acid value (PH) of the hydrazine-based reducing agent is added to the copper-based compound slurry and the reduction reaction is adjusted to 3.5 6.0. 5. The method for producing copper powder according to claim 4, wherein when the hydrazine-based reducing agent is added to the steel salt compound slurry, the acid value is adjusted in the reduction reaction with the aqueous ammonia solution. 6' The method for producing a copper powder according to the first aspect of the invention, wherein the acid value of the mud before the addition of the hydrazine-based reducing agent in the washed sub-vaporized copper slurry is adjusted to 4.1 to 6. 7 • A copper powder obtained by using the copper powder manufacturing method described in claim 1 of the patent application, 2213-10013-PF 28 200932405, characterized by: laser diffraction scattering particle size distribution measurement method # average grain The diameter 1) 5 ◦ is 0. 1 micron to 5.0 micron, and the volume accumulation of the cymbal is measured by the laser diffraction scattering particle size distribution to measure the θ distribution standard deviation SD and the aforementioned volume accumulation 1 waiter size / sleeve:! The value of SD/D5D shown by D5e is 〇. 2 to 〇. .5. 8. The copper powder according to claim 7, wherein the steel powder is less than 0.1 mass% after heat treatment in an atmosphere of atmospheric gas at a temperature of 4 minutes and 30 minutes. 2213-10013-PF 29