WO2005075133A1 - 高結晶性銀粉及びその製造方法 - Google Patents
高結晶性銀粉及びその製造方法 Download PDFInfo
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- WO2005075133A1 WO2005075133A1 PCT/JP2005/001660 JP2005001660W WO2005075133A1 WO 2005075133 A1 WO2005075133 A1 WO 2005075133A1 JP 2005001660 W JP2005001660 W JP 2005001660W WO 2005075133 A1 WO2005075133 A1 WO 2005075133A1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/07—Metallic powder characterised by particles having a nanoscale microstructure
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/12—All metal or with adjacent metals
- Y10T428/12014—All metal or with adjacent metals having metal particles
Definitions
- the present invention relates to a highly crystalline silver powder and a method for producing the same, and more specifically, for example, a chip component
- Conductive pastes that can greatly refine electrodes and circuits of plasma display panels, etc. and can be formed with high density, high accuracy and high reliability, especially fine wiring or thin and smooth coating films Fine, high-dispersion, relatively broad particle size distribution, not too sharp, and suitable for the production of conductive paste capable of forming high density, high precision and high reliability. Therefore, when used as a raw material of a conductive paste, it is excellent in dispersibility of silver powder in the paste and filling property of silver powder in the conductive paste, and further refines electrodes and circuits formed from a silver thick film. High crystalline silver powder and a method for producing the same, wherein the silver thick film obtained from the conductive paste has excellent heat shrinkage resistance and low specific resistance (resistivity). It is intended to. Background art
- the term “dispersibility” means the difficulty of agglomeration of primary particles of silver powder unless otherwise specified, such as the dispersibility of silver powder in a paste.
- a state in which dispersibility is good means that the primary particles are agglomerated with each other and the ratio of the primary particles is small or not at all.
- a substrate on which the conductive paste is printed is usually used for a portion of a ceramic substrate that generates a large amount of heat, such as an IC package. But this ceramic substrate When a conductive paste is printed on a ceramic substrate, the thermal shrinkage of the ceramic substrate is generally different from the thermal shrinkage of the silver thick film formed from the printed conductive paste. There is a possibility that the thick film is peeled off or the substrate itself is deformed. For this reason, it is preferable that the thermal shrinkage of the ceramic substrate and the thermal shrinkage of the thick silver film formed from the printed conductive paste take values as close as possible.
- silver powder in the conductive paste undergoes sintering during firing.
- silver powder is a polycrystal composed of minute crystallites.
- the fine crystallites in the silver powder are sintered. Therefore, it is considered that a dimensional change occurs before and after the formation of the silver thick film, causing heat shrinkage. For this reason, in order to obtain a silver powder-containing conductive paste with low thermal shrinkage, it is desirable that the crystallites in the silver powder be as large as possible so that sintering of the crystallites does not occur as much as possible.
- LTCC Low Temperature Co-fired Ceramic
- the number of firings is smaller, the control of the ceramic dielectric film thickness is easier, and the conductor resistance of the circuit formed from the conductive paste is reduced. And the surface smoothness of the substrate is easily improved, which is preferable in these respects.
- the LTCC has extremely excellent dimensional stability, it is strongly required that the silver powder, which is the material of the conductive paste used for the LTCC, also has a small heat shrinkage, and accordingly, the large crystallites in the silver powder are more important. It is strongly desired.
- the conductive paste containing silver powder can be used not only for the circuit formed by firing as described above but also for the circuit formed without firing.
- the silver powder used in the conductive paste is fine, has good dispersibility, has a relatively broad particle size distribution without being too sharp, and has a large crystallite.
- Patent Document 1 Japanese Patent Application Laid-Open No. 2000-1706 discloses high crystalline silver particles in which an aqueous solution of silver nitrate and a solution of an acrylic acid monomer dissolved in an aqueous solution of L-ascorbic acid are mixed and reacted simultaneously. According to this method, highly crystalline silver powder having a crystallite size of 400 A or more and a particle size in a narrow range of 2 to 4 ⁇ m can be obtained.
- Patent Document 1 Japanese Patent Application Laid-Open No. 2000-1706 (page 1)
- the silver powder described in Patent Document 1 is fine and has a large crystallite, but the heat shrinkage at a high temperature of, for example, about 700 ° C is hard to be sufficiently reduced.
- This silver powder has a large heat shrinkage at high temperature despite the crystallite being sufficiently large, because the particle size range of the silver powder is 2-4 ⁇ m and the particle size distribution is too sharp. It is presumed that this is due to the fact that voids are formed between the silver powders so that the filling property of the silver powders is reduced.
- an object of the present invention is to provide a highly crystalline silver powder which is fine, has a relatively wide particle size distribution with good dispersibility, is relatively broad, and has a large crystallite, and a method for producing the same. .
- the present inventors have conducted intensive studies and have found that silver powder is mixed by a method of mixing a first aqueous solution containing silver nitrate, a dispersant and nitric acid with a second aqueous solution containing ascorbic acid.
- the high crystallinity that makes it possible to produce a thick silver film obtained from a conductive paste with a fine grain, a relatively broad particle size distribution that is not too sharp, and a large crystallite, with excellent heat shrink resistance.
- the inventors have found that a functional silver powder can be obtained, and have completed the present invention.
- the method for producing a highly crystalline silver powder comprises a first aqueous solution containing silver nitrate, a dispersant and nitric acid.
- the liquid is mixed with a second aqueous solution containing ascorbic acid.
- the present invention also provides a method for producing a highly crystalline silver powder, wherein the dispersant is polyvinylpyrrolidone.
- the present invention also provides a method for producing a highly crystalline silver powder, wherein the dispersant is gelatin.
- the first aqueous solution may contain 5 parts by weight of polybutylpyrrolidone and 60 parts by weight of nitric acid, and 35 parts by weight of nitric acid, based on 100 parts by weight of silver nitrate.
- the present invention provides a method for producing highly crystalline silver powder, characterized in that 70 parts by weight are blended.
- the first aqueous solution may contain 0.5 parts by weight to 10 parts by weight of gelatin and 35 parts by weight to 70 parts by weight of nitric acid per 100 parts by weight of silver nitrate.
- the present invention provides a method for producing highly crystalline silver powder, characterized in that it has been blended.
- the first aqueous solution and the second aqueous solution are combined in the second aqueous solution with respect to 100 parts by weight of silver nitrate mixed in the first aqueous solution. It is intended to provide a method for producing highly crystalline silver powder, characterized in that the ascorbic acid thus obtained is mixed at a ratio of 30 parts by weight to 90 parts by weight.
- the first aqueous solution and the second aqueous solution are mixed in the first aqueous solution with respect to 100 parts by weight of ascorbic acid mixed in the second aqueous solution.
- the present invention provides a method for producing highly crystalline silver powder, characterized in that the obtained nitric acid is mixed at a ratio of 40 parts by weight to 150 parts by weight.
- the present invention also provides a highly crystalline silver powder produced by the above method for producing a highly crystalline silver powder.
- the highly crystalline silver powder produced by the method is characterized in that the crystallite diameter is 300 A or more.
- the highly crystalline silver powder has an average particle diameter D of 0.5 m to 10 m.
- the high crystalline silver powder is characterized in that the heat shrinkage at 700 ° C is within ⁇ 3%.
- the highly crystalline silver powder is characterized in that D ZD is 2.1-5.0.
- the highly crystalline silver powder has a crystallite size of 300 A or more and an average particle size D of 0.
- the highly crystalline silver powder is characterized in that D ZD is 2.1-5.0.
- the highly crystalline silver powder according to the present invention is fine, has good dispersibility, is relatively broad without too sharp particle size distribution, and has a large crystallite. It is excellent in dispersibility of silver powder in paste and filling of silver powder in conductive paste, and can further refine electrodes, circuits, etc. formed from silver thick film, and obtain silver thickness obtained from conductive paste.
- the film can have excellent heat shrink resistance and low specific resistance.
- the method for producing highly crystalline silver powder according to the present invention can efficiently produce the highly crystalline silver powder according to the present invention.
- the highly crystalline silver powder according to the present invention is a substantially granular powder.
- the highly crystalline silver powder according to the present invention has an average particle diameter D of 0.5 m to 10 m, preferably 1 ⁇ m to 5 ⁇ m.
- the silver powder has excellent silver powder filling properties and can further fine-tune circuits formed from a thick silver film.
- the average particle size D is less than 0.5 m, the silver powder
- the average particle size D is determined by the laser diffraction scattering method.
- Volume average particle size that is, the particle size at a cumulative distribution of 50%.
- the highly crystalline silver powder according to the present invention has a crystallite diameter of 300 A or more, preferably 350 A to 600 A.
- the crystallite diameter is within the above range, when the conductive paste containing the silver powder is applied to a ceramic substrate and fired to form a circuit including a silver thick film, the silver thickness before and after firing is reduced.
- the thermal shrinkage of the film approaches the thermal shrinkage of the ceramic substrate, which has a large effect of suppressing the separation of the thick silver film from the ceramic substrate and the deformation of the ceramic substrate due to the dimensional change of the thick silver film. preferable.
- the crystallite diameter refers to an average value of crystallite diameters obtained from X-ray diffraction of a silver powder sample and determined from the half-value width of the peak of the diffraction angle of each crystal plane.
- the highly crystalline silver powder according to the present invention has a D ZD of usually 2.1 to 5.0, preferably 2.5 to 4.
- D 1 and D 2 are laser diffraction scattering particles, respectively.
- the median diameter m) at 10% by volume and 90% by volume of the cumulative distribution by the degree distribution measurement method is shown.
- D ZD is an index that indicates variation. If D ZD is large, the particle size distribution will vary.
- the silver paste becomes relatively broad, and if a circuit is formed with a conductive paste using the silver powder, the silver powder has excellent filling properties, so that the circuit has excellent heat shrink resistance, that is, the circuit before and after firing. Dimensional change is small and easy to be made, so it is preferable.
- the highly crystalline silver powder according to the present invention has a heat shrinkage in the length direction at 700 ° C. of usually within ⁇ 3%, preferably within ⁇ 2%.
- “within ⁇ X%” means that X% ⁇ X%.
- the thermal shrinkage in the longitudinal direction at 700 ° C is measured by using a thermomechanical analysis (TMA) for a sample in which silver powder is formed into a pellet. The heat shrinkage in the length direction of the determined pellet.
- TMA thermomechanical analysis
- the highly crystalline silver powder according to the present invention has a low resistivity of a silver coating film fired at a relatively low temperature, for example, at 300 ° C. That is, even if the highly crystalline silver powder is sintered at a low temperature, the resistivity of the sintered product tends to decrease.
- the reason why the resistivity of the silver coating film fired at 300 ° C. is low is presumed to be that the movement of electrons in the silver powder becomes smooth due to the large crystallite diameter.
- the highly crystalline silver powder according to the present invention has a specific surface area of usually 0.1. OmVg, preferably 0.20 mg-0.90 m 2 Zg.
- the specific surface area is less than 0.10 m 2 Zg, it is difficult to finely define electrodes and circuits with a silver thick film, which is not preferable.
- the specific surface area exceeds 1.0 m 2 Zg, it is difficult to paste silver powder, which is not preferable.
- the specific surface area means a BET specific surface area.
- the highly crystalline silver powder according to the present invention has a tap density of usually 3.8 gZcm 3 or more, preferably 4.
- the highly crystalline silver powder according to the present invention can be produced, for example, by the following method.
- a first aqueous solution containing silver nitrate, a dispersant and nitric acid is mixed with a second aqueous solution containing ascorbic acid.
- the first aqueous solution is an aqueous solution containing silver nitrate, a dispersant, and nitric acid.
- the water used for preparing the first aqueous solution pure water, ion-exchanged water, ultrapure water and the like are preferable for preventing impurities from being mixed into the silver powder.
- the silver nitrate used in the present invention is not particularly limited, and any of a solid and an aqueous solution can be used.
- Examples of the dispersant used in the present invention include polyvinylpyrrolidone (PVP), gelatin, polyethylene glycol, and polybutyl alcohol.
- PVP polyvinylpyrrolidone
- gelatin is used in a concept including -force.
- Polyvinylpyrrolidone and gelatin are preferred because the heat shrink resistance of silver powder can be particularly increased.
- the dispersibility of the silver powder is improved, and the silver powder is fine and the particle size distribution is not too sharp, so that the silver powder has a relatively large action.
- the nitric acid used in the present invention is not particularly limited, and either concentrated nitric acid or diluted nitric acid can be used.
- the silver ion force is controlled so that the reaction rate for generating silver is relatively slow, so that the particle size distribution of the silver powder is made relatively broad without being too sharp. And has the effect of increasing the crystallite. If silver powder is produced without adding nitric acid, the reaction rate for producing silver from silver ions is too high and the reaction occurs immediately.
- the obtained silver powder has a small particle size and a small crystallite size.
- the first aqueous solution generally contains polyvinylpyrrolidone in an amount of 5 parts by weight to 60 parts by weight, preferably 15 parts by weight to 50 parts by weight, and more preferably 100 parts by weight of silver nitrate. Including 20 parts by weight and 40 parts by weight.
- the amount of polypyrrolidone is within the above range, the dispersibility of the silver powder is improved, and the particle size distribution of the silver powder is relatively sharp and relatively broad.
- the blending amount of polyvinylpyrrolidone is less than 5 parts by weight, the obtained silver powder is liable to agglomerate, and if it is more than 60 parts by weight, the obtained silver powder tends to have a high impurity concentration and is likely to pollute the environment. This is not preferable because the production cost tends to increase.
- the first aqueous solution generally contains 0.5 to 10 parts by weight of gelatin, preferably 1 to 18 parts by weight, and more preferably 100 to 100 parts by weight of silver nitrate. Contains 2 parts by weight to 6 parts by weight.
- the amount of gelatin is within the above range, the dispersibility of the silver powder is improved, and the particle size distribution of the silver powder is not too sharp and relatively broad, which is preferable.
- the amount of gelatin is less than 0.5 part by weight, the obtained silver powder is likely to aggregate, which is not preferable.If it exceeds 10 parts by weight, the impurity concentration in the obtained silver powder becomes high, and the environment is easily polluted. This is not preferable because the production cost tends to be high.
- the first aqueous solution generally contains 1 part by weight to 10 parts by weight, preferably 2 parts by weight to 14 parts by weight of gelatin relative to 100 parts by weight of water.
- PolyBulle It is preferable that the amount of pyrrolidone is in the above range because the dispersibility of the silver powder is improved and the particle size distribution of the silver powder is relatively sharp and relatively broad.
- the blending amount of polyvinylpyrrolidone is less than 1 part by weight, the obtained silver powder is liable to agglomerate. This is not preferable because the production cost tends to be high.
- the first aqueous solution generally contains 0.1 to 5 parts by weight, preferably 0.4 to 12 parts by weight of gelatin per 100 parts by weight of water. It is preferable that the amount of gelatin is within the above range, because the dispersibility of the silver powder is improved and the particle size distribution of the silver powder is relatively broad without being too sharp. On the other hand, if the amount of gelatin is less than 0.1 part by weight, the obtained silver powder is likely to aggregate, which is not preferable.If the amount exceeds 5 parts by weight, the impurity concentration in the obtained silver powder is easily increased, and the environment is easily polluted. This is not preferable because the production cost tends to be high.
- the first aqueous solution generally contains 35 to 70 parts by weight, preferably 40 to 60 parts by weight, and more preferably 48 to 54 parts by weight of nitric acid based on 100 parts by weight of silver nitrate.
- the amount of nitric acid is within the above range, the particle size distribution of the silver powder is not too sharp and relatively broad, and the effect of enlarging the crystallite is large.
- the amount of nitric acid is less than 35 parts by weight, the crystallinity of the silver powder tends to be low.
- the compounding amount of nitric acid means a compounding amount converted to concentrated nitric acid having a concentration of 61%.
- the second aqueous solution refers to an aqueous solution containing ascorbic acid.
- Ascorbic acid used in the present invention may be an L-form or a D-form.
- the first aqueous solution and the second aqueous solution are mixed to precipitate a highly crystalline silver powder in the mixed solution.
- a mixed form for example, there is a method in which a first aqueous solution is stirred and a second aqueous solution is added thereto.
- the whole amount of the second aqueous solution may be added to the first aqueous solution at once, or the second aqueous solution may be gradually added to the first aqueous solution little by little.
- the dispersant in the first aqueous solution is -In the case of rupyrrolidone
- the method of adding the entire amount of the second aqueous solution to the first aqueous solution at once is preferable because it is easy to obtain silver powder that is fine, has a too narrow particle size distribution, and is relatively broad.
- the dispersant therein is gelatin, it is preferable to employ a method in which the second aqueous solution is gradually added to the first aqueous solution little by little because the particle size of silver powder can be easily controlled.
- ascorbic acid force blended in the second aqueous solution is usually 30 parts by weight to 90 parts by weight based on 100 parts by weight of silver nitrate blended in the first aqueous solution.
- they are mixed at a ratio of 40 parts by weight to 80 parts by weight, more preferably 50 parts by weight to 75 parts by weight.
- the amount of ascorbic acid is preferable for the amount of ascorbic acid to be in the above range with respect to silver nitrate, because the yield of silver powder tends to increase.
- the amount of ascorbic acid is less than 30 parts by weight relative to 100 parts by weight of silver nitrate, the reduction is insufficient and the yield of silver powder tends to be low. Exceeding the weight is not preferable because it easily pollutes the environment and increases the production cost.
- the first aqueous solution and the second aqueous solution are mixed, they are mixed at a ratio such that the silver ion concentration in the obtained mixed solution is usually lOgZl-80gZl, preferably 30gZl-65gZl. It is preferable that the silver ion concentration in the mixed solution is within the above range, since the yield of silver powder is high and the obtained silver powder is hard to aggregate. On the other hand, if the silver ion concentration is less than 10 gZi, the productivity of the silver powder tends to deteriorate, and if the silver ion concentration exceeds 80 gZl, the obtained silver powder tends to aggregate, which is not preferable.
- the nitric acid mixed with the first aqueous solution is usually 40 parts by weight based on 100 parts by weight of ascorbic acid mixed in the second aqueous solution.
- 150 parts by weight preferably 50 parts by weight to 120 parts by weight, more preferably 65 parts by weight to 100 parts by weight. It is preferable that the amount of nitric acid with respect to ascorbic acid is within the above range, since the yield of silver powder tends to increase.
- the amount of nitric acid is less than 40 parts by weight with respect to 100 parts by weight of ascorbic acid, it is difficult to sufficiently increase the crystallite size of the obtained silver powder. If the compounding amount exceeds 150 parts by weight, the obtained silver powder is liable to agglomerate, which is not preferable.
- the silver powder precipitated in the mixed solution is mixed with the first aqueous solution.
- the silver powder is allowed to grow in the mixed solution by continuing to mix the mixed solution for at least 3 minutes, preferably for 5 minutes to 10 minutes, and the particle size, particle size distribution and dispersibility of the silver powder
- the silver powder according to the present invention easily falls within a specific range, and thus is preferred.
- the silver powder obtained in the mixed solution is filtered, for example, with a filter means such as Nutsche, and then the filter cake is washed with pure water and dried to obtain the highly crystalline silver powder according to the present invention.
- the highly crystalline silver powder according to the present invention is used, for example, as a raw material for a conductive paste capable of forming electrodes and circuits of chip components, plasma display panels, glass ceramic packages, ceramic filters, and the like.
- a conductive paste capable of forming electrodes and circuits of chip components, plasma display panels, glass ceramic packages, ceramic filters, and the like.
- it can be used not only as a substrate for forming circuits but also as a raw material for conductive paste for LTCC substrates as well as ordinary ceramic substrates. can do .
- the method for producing highly crystalline silver powder according to the present invention can be used for producing the highly crystalline silver powder according to the present invention.
- a first aqueous solution was prepared by adding 10g of PVP (K value: 30), 50g of silver nitrate and 24.6g of concentrated nitric acid (concentration of 61%) to 500g of pure water at normal temperature, stirring and dissolving (first aqueous solution A). ). On the other hand, 35.8 g of ascorbic acid was added to 500 g of pure water at room temperature, stirred and dissolved to prepare a second aqueous solution (second aqueous solution A). Tables 1 and 2 show the compositions of the first aqueous solution and the second aqueous solution.
- the first aqueous solution A was stirred, the second aqueous solution A was added to the first aqueous solution A at a time, and after the addition was completed, the mixture was further stirred for 5 minutes to grow particles in the mixed solution. . Then, the stirring was stopped, and the particles in the mixed solution were settled. The supernatant of the mixed solution was discarded, the mixed solution was filtered using a nutsche, and the filter cake was washed with pure water, dried, and dried to obtain a high crystal. Silver powder was obtained.
- D, D, D, D, D, D, D, SD crystallite diameter, specific surface area, tap density
- the particle size at the time when the cumulative distribution determined by the one-diffraction scattering method is 10%, 50%, 90%, and 100% is Dm), Dm), Dm), and Dm), respectively.
- the standard deviation of the obtained particle size distribution was defined as SD.
- Crystallite diameter Powder X-ray diffraction was performed using an X-ray diffractometer RINT2000PC manufactured by Rigaku Corporation, and the half-width force at the peak of the diffraction angle of each obtained crystal plane was determined.
- Specific surface area The BET specific surface area measured using Monosoap manufactured by urea sio-tas Co., Ltd. was used.
- Tap density The tap density was measured by tapping the sample using a tap denser manufactured by Kuramochi Kagaku Kikai Seisakusho.
- Thermal shrinkage A columnar pellet is prepared by compressing silver powder, and using TMAZSS6300 manufactured by Seiko Instruments Inc., the pellet is heated from room temperature at a temperature rising rate of 10 ° CZmin in Air. TMA analysis was performed up to 850 ° C, and the heat shrinkage in the length direction of the pellet was measured. The measurement temperatures were 300 ° C, 500 ° C and 700 ° C.
- a mixed solvent is prepared by mixing 95 parts by weight of terbineol and 5 parts by weight of ethyl cellulose, and a paste is prepared by mixing 15 parts by weight of the mixed solvent and 85 parts by weight of the sample powder.
- the paste was fired at 300 ° C. to produce a silver coating having a thickness of about several zm. Further, a silver coating film was prepared in the same manner as above except that the firing temperature was changed to 400 ° C and 500 ° C instead of 300 ° C.
- the resistance ( ⁇ ) of the silver coating film was measured by a four-terminal method using (Milliohm Meter, manufactured by Hewlett-Packard Co., Ltd.), and the resistivity was determined from the cross-sectional area of the silver coating film and the length between the terminals. p ( ⁇ ⁇ ⁇ ) was determined.
- a first aqueous solution was prepared by adding 20 g of PVP (K value: 30), 50 g of silver nitrate and 24.6 g of concentrated nitric acid (concentration of 61%) to 500 g of pure water at room temperature, stirring and dissolving (first aqueous solution B).
- first aqueous solution B 50 g of silver nitrate and 24.6 g of concentrated nitric acid (concentration of 61%)
- first aqueous solution B 35.8 g of ascorbic acid was added to 500 g of pure water at room temperature, stirred and dissolved to prepare a second aqueous solution (second aqueous solution A).
- Tables 1 and 2 show the compositions of the first aqueous solution and the second aqueous solution.
- the first aqueous solution B was stirred, the second aqueous solution A was added to the first aqueous solution B all at once, and after the addition was completed, the mixture was further stirred for 5 minutes to grow particles in the mixed solution. . Then, the stirring was stopped, and the particles in the mixed solution were settled. The supernatant of the mixed solution was discarded, the mixed solution was filtered using a nutsche, and the filter cake was washed with pure water, dried, and dried to obtain a high crystal. Silver powder was obtained. With respect to the obtained silver powder, D, D, D, D, SD, crystallite were obtained in the same manner as in Example 1.
- a first aqueous solution was prepared by adding 10 g of PVP (K value: 30) and 50 g of silver nitrate to 500 g of pure water at ordinary temperature, stirring and dissolving (first aqueous solution C).
- first aqueous solution C 50 g of silver nitrate
- second aqueous solution B 26 g of ascorbic acid was added to 500 g of pure water at room temperature, stirred and dissolved to prepare a second aqueous solution.
- Tables 1 and 2 show the compositions of the first aqueous solution and the second aqueous solution.
- the first aqueous solution C was stirred, and the second aqueous solution B was added all at once to the first aqueous solution C. After the addition was completed, the mixture was further stirred for 5 minutes to grow particles in the mixed solution. . After that, stirring was stopped, and the particles in the mixed solution were settled. The supernatant of the mixed solution was discarded, the mixed solution was filtered using a nutsche, the residue was washed with pure water, dried, and the silver powder was removed. Obtained.
- the first aqueous solution D at 50 ° C was stirred, and the second aqueous solution C at room temperature was gradually added to the first aqueous solution D over 30 minutes, and after the addition was completed, the mixture was further stirred for 5 minutes. The particles grew in the mixture. After that, stirring was stopped, and the particles in the mixed solution were allowed to settle. Then, the supernatant of the mixed solution was discarded, the mixed solution was filtered using Nutsche, and the filter cake was washed with pure water, dried, and dried to obtain highly crystalline silver powder. Got.
- Gelatin manufactured by Nitta Gelatin Co., Ltd. 3. Add Og, 50 g of silver nitrate and 24.6 g of concentrated nitric acid (concentration of 61%) to 500 g of pure water at room temperature, and heat to 50 ° C and stir to mix them. This was dissolved to prepare a first aqueous solution (first aqueous solution E). On the other hand, 25.9 g of ascorbic acid was added to 500 g of pure water at room temperature, stirred and dissolved to prepare a second aqueous solution (second aqueous solution D). Tables 1 and 2 show the compositions of the first aqueous solution and the second aqueous solution.
- the first aqueous solution E at 50 ° C was stirred, and the second aqueous solution D at room temperature was gradually added to the first aqueous solution E over 30 minutes, and after the addition was completed, the mixture was further stirred for 5 minutes. The particles grew in the mixture. After that, stirring was stopped, and the particles in the mixed solution were allowed to settle. Then, the supernatant of the mixed solution was discarded, the mixed solution was filtered using Nutsche, and the filter cake was washed with pure water, dried, and dried to obtain highly crystalline silver powder. Got.
- Example 1 0.13 -2.13-2.2
- Example 2 0.09-2.68 -2.9 Comparative example 1 0.84 -4.02 -7.82
- Example 3 0.27 1.08 1.13
- Example 4 -0.58 -1.51 -1.35
- the silver powder produced using the dispersant and nitric acid has a large crystallite size, is highly crystalline, and has a small heat shrinkage at 700 ° C.
- those using gelatin as a dispersant have a small heat shrinkage especially at 700 ° C.
- the resistivity p of the silver coating film fired at 300 ° C is lower in the silver powder produced using the dispersant and the nitric acid than in the silver powder produced without using the nitric acid. This is presumed to be because the movement of electrons in the silver powder becomes smooth due to the large crystallite diameter.
- the highly crystalline silver powder and the method for producing the highly crystalline silver powder according to the present invention include, for example, a chip part.
- a raw material for conductive paste that can form electrodes and circuits for products, plasma display panels, glass ceramic packages, ceramic filters, etc. and is particularly suitable as a raw material for conductive paste for LTCC substrates Can be used for
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Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
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KR1020067018248A KR101215458B1 (ko) | 2004-02-10 | 2005-02-04 | 고결정성 은분 및 그 제조 방법 |
EP05709726A EP1721690A1 (en) | 2004-02-10 | 2005-02-04 | Highly crystalline silver powder and method for production thereof |
US10/588,970 US20090023007A1 (en) | 2004-02-10 | 2005-02-04 | Highly crystalline silver powder and method for producing the same |
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Application Number | Priority Date | Filing Date | Title |
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JP2004-034121 | 2004-02-10 | ||
JP2004034121A JP4976642B2 (ja) | 2004-02-10 | 2004-02-10 | 高結晶性銀粉及びその製造方法 |
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US (1) | US20090023007A1 (ja) |
EP (1) | EP1721690A1 (ja) |
JP (1) | JP4976642B2 (ja) |
KR (1) | KR101215458B1 (ja) |
CN (1) | CN1925941A (ja) |
TW (1) | TWI286090B (ja) |
WO (1) | WO2005075133A1 (ja) |
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63307206A (ja) * | 1987-06-08 | 1988-12-14 | Tanaka Kikinzoku Kogyo Kk | 銀微粒子の製造方法 |
JPH01104338A (ja) * | 1987-10-15 | 1989-04-21 | Tanaka Kikinzoku Kogyo Kk | 銀コロイドの製造方法 |
JP2000001706A (ja) * | 1998-06-17 | 2000-01-07 | Tanaka Kikinzoku Kogyo Kk | 高結晶体銀粒子及びその製造方法ならびに高結晶体銀粒子からなる導体ペースト |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000001707A (ja) * | 1998-06-17 | 2000-01-07 | Tanaka Kikinzoku Kogyo Kk | 銀粒子及びその製造方法ならびに銀粒子からなる導体ペースト |
JP2000265225A (ja) * | 1999-03-15 | 2000-09-26 | Aida Kagaku Kogyo Kk | 貴金属高強度焼結体の製造方法及び貴金属高強度焼結体 |
-
2004
- 2004-02-10 JP JP2004034121A patent/JP4976642B2/ja not_active Expired - Lifetime
-
2005
- 2005-02-04 CN CNA2005800063565A patent/CN1925941A/zh active Pending
- 2005-02-04 EP EP05709726A patent/EP1721690A1/en not_active Withdrawn
- 2005-02-04 US US10/588,970 patent/US20090023007A1/en not_active Abandoned
- 2005-02-04 TW TW094103609A patent/TWI286090B/zh not_active IP Right Cessation
- 2005-02-04 WO PCT/JP2005/001660 patent/WO2005075133A1/ja not_active Application Discontinuation
- 2005-02-04 KR KR1020067018248A patent/KR101215458B1/ko not_active IP Right Cessation
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS63307206A (ja) * | 1987-06-08 | 1988-12-14 | Tanaka Kikinzoku Kogyo Kk | 銀微粒子の製造方法 |
JPH01104338A (ja) * | 1987-10-15 | 1989-04-21 | Tanaka Kikinzoku Kogyo Kk | 銀コロイドの製造方法 |
JP2000001706A (ja) * | 1998-06-17 | 2000-01-07 | Tanaka Kikinzoku Kogyo Kk | 高結晶体銀粒子及びその製造方法ならびに高結晶体銀粒子からなる導体ペースト |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
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WO2007143125A2 (en) | 2006-06-02 | 2007-12-13 | E. I. Du Pont De Nemours And Company | Process for making highly dispersible spherical silver powder particles and silver particles formed therefrom |
WO2007143125A3 (en) * | 2006-06-02 | 2008-01-31 | Du Pont | Process for making highly dispersible spherical silver powder particles and silver particles formed therefrom |
CN101460271A (zh) * | 2006-06-02 | 2009-06-17 | E.I.内穆尔杜邦公司 | 制备可高度分散的球形银粉颗粒的方法和由此形成的银颗粒 |
JP2009540111A (ja) * | 2006-06-02 | 2009-11-19 | イー・アイ・デュポン・ドウ・ヌムール・アンド・カンパニー | 高分散性球状銀粉末粒子の製造方法およびそれから形成された銀粒子 |
US7648557B2 (en) | 2006-06-02 | 2010-01-19 | E. I. Du Pont De Nemours And Company | Process for making highly dispersible spherical silver powder particles and silver particles formed therefrom |
JP2008179851A (ja) * | 2007-01-24 | 2008-08-07 | Mitsui Mining & Smelting Co Ltd | 銀粉の製造方法及び銀粉 |
CN101716685B (zh) * | 2009-12-14 | 2011-08-24 | 昆明理工大学 | 化学还原法制备球形超细银粉的方法 |
CN102133635A (zh) * | 2011-05-02 | 2011-07-27 | 杨荣春 | 银粉及其制造方法 |
WO2017073057A1 (ja) * | 2015-10-30 | 2017-05-04 | Dowaエレクトロニクス株式会社 | 銀粉およびその製造方法 |
JP2017082327A (ja) * | 2015-10-30 | 2017-05-18 | Dowaエレクトロニクス株式会社 | 銀粉およびその製造方法 |
KR20180075582A (ko) * | 2015-10-30 | 2018-07-04 | 도와 일렉트로닉스 가부시키가이샤 | 은 분말 및 그 제조 방법 |
US10828702B2 (en) | 2015-10-30 | 2020-11-10 | Dowa Electronics Materials Co., Ltd. | Silver powder and method for producing same |
JP2021075799A (ja) * | 2015-10-30 | 2021-05-20 | Dowaエレクトロニクス株式会社 | 銀粉およびその製造方法 |
JP7110421B2 (ja) | 2015-10-30 | 2022-08-01 | Dowaエレクトロニクス株式会社 | 銀粉およびその製造方法 |
US11407030B2 (en) | 2015-10-30 | 2022-08-09 | Dowa Electronics Materials Co., Ltd. | Silver powder and method for producing same |
KR102446788B1 (ko) | 2015-10-30 | 2022-09-22 | 도와 일렉트로닉스 가부시키가이샤 | 은 분말 및 그 제조 방법 |
Also Published As
Publication number | Publication date |
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US20090023007A1 (en) | 2009-01-22 |
EP1721690A1 (en) | 2006-11-15 |
JP2005226094A (ja) | 2005-08-25 |
KR101215458B1 (ko) | 2012-12-26 |
KR20070018025A (ko) | 2007-02-13 |
CN1925941A (zh) | 2007-03-07 |
JP4976642B2 (ja) | 2012-07-18 |
TW200536636A (en) | 2005-11-16 |
TWI286090B (en) | 2007-09-01 |
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