CN103480855A - Preparation method of superfine copper powder for copper paste - Google Patents

Preparation method of superfine copper powder for copper paste Download PDF

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CN103480855A
CN103480855A CN201310203330.6A CN201310203330A CN103480855A CN 103480855 A CN103480855 A CN 103480855A CN 201310203330 A CN201310203330 A CN 201310203330A CN 103480855 A CN103480855 A CN 103480855A
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copper
preparation
powder
mixed
liquor
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颜首文
颜子舒
罗道林
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Kunming Story Science And Technology Ltd
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Abstract

The invention discloses a preparation method of superfine copper powder for copper paste. The method comprises the steps of preparation of a solution, preparation of mixed liquid, washing, reducing, cleaning, drying and packaging. According to the method, operation can be performed at normal temperature and under normal pressure, raw materials can be obtained from the market, equipment does not need to be customized separately, only conventional stirrers and reaction kettles are needed, the copper ion reduction degree is high, the copper powder yield is high, the particle diameter of the copper powder is uniform, the purity of the copper powder is high, the raw materials have wide sources and are low in prices, and the process flow is simple; the method is suitable to popularize and use rapidly.

Description

The preparation method of superfine cupper powder for a kind of copper slurry
Technical field
The present invention relates to obtain in class of jobs powder metallurgy the manufacturing technology field of metal dust from the liquid metals compound, the preparation method of superfine cupper powder for espespecially a kind of copper slurry.
Background technology
Superfine cupper powder uses very extensive in modern conductance technology, especially the use in electric slurry is very important, electric slurry is the material that microelectronic element must be used, it is the basic material of manufacturing thick film element, it is a kind of paste mixed through three-roll rolling by pressed powder and organic solvent, electric slurry main component prior art adopts silver powder or copper powder more, its Main Function is conductive powder and electronic component is mobile phone, household electrical appliance, computer, digital camera, the base components of video camera, consumption is very big, concrete by the purposes difference, be divided into dielectric paste, resistance slurry and conductor paste: by the substrate kind, be divided into ceramic substrate, polymer matrix film, glass substrate and metal-insulator substrate electric slurry etc., by the sintering temperature difference, can be divided into high temperature, middle gentle low temperature drying electric slurry, by the purposes difference, can be divided into universal electric slurry (making general thick film circuit) and special electronic slurry (stainless steel substrate electric slurry, Thermistor), price by conductive phase is divided into noble metal electric slurry (silver-colored palladium, ruthenium system and gold paste etc.) and base metal electric slurry (molybdenum manganese slurry), the domestic electric slurry of prior art mostly is use silver powder, because higher general of these electric slurry prices that cause of silver-colored price are higher, copper was a kind of desirable powder stock originally, but due to the imperfection of prior art, cause the production and processing requirement high, cost is also restive, cause the copper powder manufacturing technology to be difficult to promote, practicality is lower.
The preparation method who is used as at present the copper nanoparticle of electric slurry mainly is divided into Physical and the large class of chemical method two, wherein Physical comprises physical vapour deposition (PVD), the methods such as high-energy ball milling, its energy consumption is large, yield poorly, made copper powder activity is lower, be not suitable for large-scale industrial production, and chemical method particularly wet chemistry method be that a kind of energy consumption is low, output is large, the active a kind of high method of made copper powder, be applicable to large-scale industrial production, but there is again the large problem of copper ion remaining quantity in solution in practical operation, another kind is that hydro-thermal method claims again hydrothermal method, the category that belongs to liquid phase chemical, refer in the pressure vessel of sealing, take water as solvent, the chemical reaction carried out at certain temperature and pressure.With respect to additive method, the particle prepared in hydrothermal reaction process has even particle size distribution, crystal grain is grown complete, purity is high, particle agglomeration is lighter, can use the comparatively cheap characteristics such as raw material, and hydro-thermal reaction is generally carried out in high-temperature kettle, can avoid noxious material to volatilize in course of reaction, but the prior art surface high-temp can strengthen the freedom of mantoquita and copper ion in solution, its amount be dissolved in solution is increased, that the final copper powder quantity obtained descends, existing wet chemistry method is all that single high-purity mantoquita is dissolved in deionized water and is reacted, but those skilled in the art can be known mantoquita and nearly all be insoluble in water, the water yield needed when it dissolves is larger, simultaneously in production process for preventing that agglomerate from also needing to add dispersant, and in really producing, need to heat or high temperature is assisted more, the production technology operation requirements is higher, production equipment high in cost of production problem.
The Chinese patent of the patent No.: CN201110020377.X, a kind of nano copper powder for electronic paste and manufacture craft thereof, feature is under the temperature and pressure produced in hydro-thermal method, to utilize the reducing agent reduction to prepare copper nanoparticle, can prepare the copper nanoparticle of different-shape and particle diameter under the condition of different temperature, pressure, reducing agent, dispersant.At first the aqueous solution of complexing agent is added in the aqueous solution of water-soluble mantoquita, form the aqueous solution of the complex compound of copper, then adding appropriate dispersant to stir is uniformly dispersed it, add again appropriate reducing agent, the mixed liquor of final gained is added with in teflon-lined stainless steel high temperature reactor, be heated to uniform temperature, the insulation certain hour, then naturally drop to room temperature, filter out precipitation, with deionized water and ethanol, clean several times, vacuum drying, finally make the copper nanoparticle highly purified, high surface, that granularity is controlled.The principle of the disclosed technology of this patent and prior art is comparatively approaching, all directly to adopt mantoquita to be dissolved in deionized water, reduce again and obtain copper powder, but in this process, added nanometer copper particle to play separating out of guiding copper powder, the method fails to break away from the drawback that prior art is directly used mantoquita to be operated, and true whole operating process also must use dispersant, the copper ion simultaneously be dissolved in solution is also more, and the reduction eduction rate is lower.
The Chinese patent of the patent No.: CN201210281119.1, disclose the preparation method of a kind of electric slurry with superfine cupper powder, relates to the electric slurry field.The purpose of this invention is to provide the preparation method of a kind of electric slurry with superfine cupper powder, be included in copper salt solution and add dispersant and reducing agent restores copper simple substance, it is characterized in that: before adding dispersant and reducing agent, first in copper salt solution, add nanometer copper particle, the particle diameter of described nanometer copper particle is 5 ~ 20nm, and the addition of described nanometer copper particle is 0.3 ‰ ~ 6 ‰ of mantoquita quality in copper salt solution.The mantoquita that the disclosed technology of this patent still adopts directly is dissolved in deionized water, directly after complexing, add the reducing agent reduction and obtain copper powder, need to add dispersant equally, and really this technique is to need to react under hot conditions, need again temperature reduction technology after pyroreaction, with the patent No.: do not use copper nanoparticle although the Chinese patent of CN201110020377.X is compared, but need to use high-temperature technology, the copper sample needs higher production technology and the production equipment of higher cost, is not suitable for rapid large-scale and promotes.
Summary of the invention
For addressing the above problem, the invention provides the preparation method of a kind of copper slurry with superfine cupper powder, the method can be operated at normal temperatures and pressures, the raw material that use can obtain on the market, do not need independent equipment for customizing, some agitators, the reactor of traditional handicraft can complete, and the copper ion reduction degree is high, it is high that copper powder obtains rate, copper powder size is even, and copper powder purity is high, the extensive low price of raw material sources, technological process is succinct, is suitable for Rapid Popularization and uses.
For achieving the above object, the present invention has adopted following technology to realize, the preparation method of superfine cupper powder for a kind of copper slurry, and its step comprises obtain solution, mixed liquor preparation, takes out and wash, reduce, clean, dry, pack, and the concrete operations of the method are as follows:
Figure DEST_PATH_DEST_PATH_IMAGE001
obtain solution: copper sulphate is mixed with deionized water, obtain copper-bath; Sodium carbonate is mixed with deionized water, obtain sodium carbonate liquor;
Figure DEST_PATH_DEST_PATH_IMAGE002
mixed liquor preparation: copper-bath is mixed with sodium carbonate liquor, and be stirred well to PH<7 and get final product;
Figure DEST_PATH_DEST_PATH_IMAGE003
take out and wash: the copper carbonate solution that obtains after reaction is precipitated, add again proper amount of clear water to clean after pumping supernatant liquor, with clear water, mix after cleaning and precipitate again, pump again supernatant liquor after precipitation, add complexing agent abundant stirring in remaining copper carbonate solution;
Figure DEST_PATH_DEST_PATH_IMAGE004
reduction: add hydrazine hydrate (N 2h 4h 2o) reduced, and fully stirred, obtained red flour;
Figure DEST_PATH_DEST_PATH_IMAGE005
clean: flour is put into to suction filtration tank and clean to neutral with clear water, obtain wet-milling;
Figure DEST_PATH_DEST_PATH_IMAGE006
dry: wet-milling is put into to vacuum drier and dry;
Figure DEST_PATH_DEST_PATH_IMAGE007
packing: pack the copper powder of drying with vacuum packing machine.
As a further improvement on the present invention, copper-bath and sodium carbonate liquor mixed proportion are 1:0.0001～1.
As a further improvement on the present invention, the described number of times of washing of taking out is 1～1000 time, wash cycles.
As a further improvement on the present invention, described complexing agent comprises industrial complexing agent, experiment level complex compound.
As a further improvement on the present invention, the addition of described hydrazine hydrate for stopping adding hydrazine hydrate when stable red flour occurring.
As a further improvement on the present invention, described oven dry is for drying wet-milling to room temperature and get final product.
As a further improvement on the present invention, for ease of collecting and subsequent treatment, in the red flour in described reduction, add terpinol, rosin wherein one or both auxiliary agents of founding stirred, carry out surface treatment.
Operation principle: the present invention selects raw material by the character of intermediate material, by the observation and comparison to Kocide SD and copper carbonate, copper carbonate is relatively stable, reaction to back can be controlled, thereby finally control the size of powder, the size distribution of powder is concentrated evenly, at the slurry of making, appropriate thixotropy is arranged, improve the printing adaptability of slurry, the moderate powder of particle diameter can be used on the electronic component of middle high-temperature sintering, when controlling reaction environment, the pH value that closes key control solution reaches the adequacy of reduction, and one of material used is strong base-weak acid salt for one of strong acid weak base salt, react a rear difficult water-soluble weak acid and weak base salt, one is highly basic strong acid salt soluble in water, both water-soluble pH values are all aobvious neutral, and the present invention is the key step of whole technique to the control of solution pH value, and the selection of two materials is all very applicable, and true two one of gains of reaction are lyotropes, one is the indissoluble thing, can impel and react carry out very thorough, that free copper ion concentration in solution is minimum, the rate that exchanges for of copper powder and the waste of minimizing material have greatly been improved greatly, the selection of complexing agent is also very important, can promote reduction reaction, by having occurred the result of generality in the development process to powder, the material particle diameter that molecular weight is little is also little, the ratio silver powder that can do such as copper powder is tiny, the copper powder that the copper powder that Kocide SD is made is made than copper carbonate is tiny, this provides reference principle to powder process, the material size of take is requirement is produced on the selection raw material, during intermediate product, should consider the molecular weight of material.
The comparison of product technology performance level and similar products at home and abroad.
Although this Project Product day present technique taiwan products size distribution does not have that it is narrow but granularity is little, a more domestic Granularity Distribution is narrow, concentrate.
  
This Project Product is as shown in the table with the Data Comparison of Related product:
Granularity (μ m) Taiwan Products obtained therefrom of the present invention Domestic
D10 1.35 0.72 0.6
D50 7.12 3.70 6.27
D90 15.06 13.30 14.84
D97 18.90 17.70 18.52
The present invention compared with prior art has following beneficial effect:
Figure DEST_PATH_118267DEST_PATH_IMAGE001
the method can be operated at normal temperatures and pressures, the raw material that use can obtain on the market, do not need independent equipment for customizing, some agitators, the reactor of traditional handicraft can complete, and the copper ion reduction degree is high, it is high that copper powder obtains rate, copper powder size is even, and copper powder purity is high, the extensive low price of raw material sources, technological process is succinct, is suitable for Rapid Popularization and uses;
Figure DEST_PATH_97725DEST_PATH_IMAGE002
the copper content of copper powder is high, particle diameter is little, easy dispersion, be difficult for oxidized, without adding separately dispersant.
Figure DEST_PATH_877462DEST_PATH_IMAGE003
production technology provided by the present invention is safe and reliable, the material that intermediate product in production process and product are discharged does not belong to poisonous and harmful substance, simultaneously because the extraction degree to copper ion in technical process is high, the Cu in waste water content of discharge is low, can reduce greatly after the expense of wastewater treatment and blowdown natural harm.
Figure DEST_PATH_334988DEST_PATH_IMAGE004
running cost of the present invention is low, production cost is low, the process equipment highly versatile, the raw materials wide material sources, thus can be lower because adopted the initial purity of chemical reaction pretreatment raw materials for production to require, brought declining to a great extent of cost.
The accompanying drawing explanation
(nothing)
The specific embodiment
Embodiment 1
The preparation method of superfine cupper powder for a kind of copper slurry, the concrete operations of the method are as follows,
Figure DEST_PATH_149360DEST_PATH_IMAGE001
, obtain solution: copper sulphate is mixed with deionized water, obtains copper-bath; Sodium carbonate is mixed with deionized water, obtain sodium carbonate liquor;
Figure DEST_PATH_34140DEST_PATH_IMAGE002
mixed liquor preparation: copper-bath is mixed with sodium carbonate liquor, and be stirred well to PH<7 and get final product;
take out and wash: the copper carbonate solution that obtains after reaction is precipitated, add again proper amount of clear water to clean after pumping supernatant liquor, with clear water, mix after cleaning and precipitate again, pump again supernatant liquor after precipitation, add complexing agent abundant stirring in remaining copper carbonate solution;
Figure DEST_PATH_562390DEST_PATH_IMAGE004
reduction: add hydrazine hydrate (N 2h 4h 2o) reduced, and fully stirred, obtained red flour;
Figure DEST_PATH_293585DEST_PATH_IMAGE005
clean: flour is put into to suction filtration tank and clean to neutral with clear water, obtain wet-milling;
dry: wet-milling is put into to vacuum drier and dry;
Figure DEST_PATH_103596DEST_PATH_IMAGE007
packing: pack the copper powder of drying with vacuum packing machine.
As of the present invention, be described in further detail, copper-bath and sodium carbonate liquor mixed proportion are 1:0.0001～1, the described number of times of washing of taking out is 1～1000 time, described complexing agent is industrial complexing agent, experiment level complex compound, described hydrazine hydrate for stopping adding hydrazine hydrate when stable red flour occurring, described oven dry is for drying wet-milling to room temperature and get final product, for ease of collecting and subsequent treatment, in red flour in described reduction, add terpinol, rosin wherein one or both auxiliary agents of founding stirred, carry out surface treatment.
Embodiment 2
Operating procedure is embodiment 1 simultaneously, and concrete copper-bath is corresponding to table with sodium carbonate liquor mixed proportion and stirring number of times:
Sequence number Copper-bath and sodium carbonate liquor mixed proportion Stir number of times
1 1：0.0001 1
2 1:0.001 100
3 1:0.01 200
4 1:0.1 300
5 1:1 400
6 1：0.0002 500
7 1：0.02 600
8 1：0.2 700
9 1：0.002 50
10 1:0.005 1000

Claims (6)

1. a copper is starched the preparation method with superfine cupper powder, and its step comprises obtain solution, mixed liquor preparation, takes out and wash, reduce, clean, dry, pack, and it is characterized in that: the concrete operations of the method are as follows,
Figure 2013102033306100001DEST_PATH_IMAGE002
, obtain solution: copper sulphate is mixed with deionized water, obtains copper-bath; Sodium carbonate is mixed with deionized water, obtain sodium carbonate liquor;
Figure 2013102033306100001DEST_PATH_IMAGE004
mixed liquor preparation: copper-bath is mixed with sodium carbonate liquor, and be stirred well to PH<7 and get final product;
Figure 2013102033306100001DEST_PATH_IMAGE006
take out and wash: the copper carbonate solution that obtains after reaction is precipitated, add again proper amount of clear water to clean after pumping supernatant liquor, with clear water, mix after cleaning and precipitate again, pump again supernatant liquor after precipitation, add complexing agent abundant stirring in remaining copper carbonate solution;
Figure 2013102033306100001DEST_PATH_IMAGE008
reduction: add hydrazine hydrate to be reduced, and fully stir, obtain red flour;
Figure DEST_PATH_IMAGE010
clean: flour is put into to suction filtration tank and clean to neutral with clear water, obtain wet-milling;
Figure DEST_PATH_IMAGE012
dry: wet-milling is put into to vacuum drier and dry;
Figure DEST_PATH_IMAGE014
packing: pack the copper powder of drying with vacuum packing machine.
2. a kind of copper is starched the preparation method with superfine cupper powder according to claim 1, and it is characterized in that: copper-bath and sodium carbonate liquor mixed proportion are 1:0.0001～1.
3. a kind of copper is starched the preparation method with superfine cupper powder according to claim 1, and it is characterized in that: the described number of times of washing of taking out is 1～1000 time, wash cycles.
4. a kind of copper is starched the preparation method with superfine cupper powder according to claim 1, it is characterized in that: the addition of described hydrazine hydrate for stopping adding hydrazine hydrate when stable red flour occurring.
5. the preparation method of superfine cupper powder for a kind of copper slurry according to claim 1 is characterized in that: described oven dry gets final product for wet-milling being dried to room temperature.
6. the preparation method of superfine cupper powder for a kind of copper slurry according to claim 1 is characterized in that: in the red flour in described reduction, add terpinol, rosin wherein one or both auxiliary agents of founding stirred, carry out surface treatment.
CN201310203330.6A 2013-05-28 2013-05-28 Preparation method of superfine copper powder for copper paste Pending CN103480855A (en)

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CN105170996A (en) * 2015-09-30 2015-12-23 金川集团股份有限公司 Preparation method of ultrafine copper powder for chip multilayer ceramic capacitors
CN110267755A (en) * 2017-02-07 2019-09-20 大阳日酸株式会社 Copper particle and its manufacturing method and sintered body
CN110303168A (en) * 2019-08-06 2019-10-08 郴州市金贵银业股份有限公司 A kind of preparation method of nano-silver powder

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Publication number Priority date Publication date Assignee Title
CN105170996A (en) * 2015-09-30 2015-12-23 金川集团股份有限公司 Preparation method of ultrafine copper powder for chip multilayer ceramic capacitors
CN110267755A (en) * 2017-02-07 2019-09-20 大阳日酸株式会社 Copper particle and its manufacturing method and sintered body
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CN110303168A (en) * 2019-08-06 2019-10-08 郴州市金贵银业股份有限公司 A kind of preparation method of nano-silver powder

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Application publication date: 20140101