CN117862520A - Method for preparing flake silver powder by using shellac - Google Patents
Method for preparing flake silver powder by using shellac Download PDFInfo
- Publication number
- CN117862520A CN117862520A CN202410269899.0A CN202410269899A CN117862520A CN 117862520 A CN117862520 A CN 117862520A CN 202410269899 A CN202410269899 A CN 202410269899A CN 117862520 A CN117862520 A CN 117862520A
- Authority
- CN
- China
- Prior art keywords
- solution
- silver
- silver powder
- preparing
- flake
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 title claims abstract description 231
- 238000000034 method Methods 0.000 title claims abstract description 50
- 229920001800 Shellac Polymers 0.000 title claims abstract description 41
- ZLGIYFNHBLSMPS-ATJNOEHPSA-N shellac Chemical compound OCCCCCC(O)C(O)CCCCCCCC(O)=O.C1C23[C@H](C(O)=O)CCC2[C@](C)(CO)[C@@H]1C(C(O)=O)=C[C@@H]3O ZLGIYFNHBLSMPS-ATJNOEHPSA-N 0.000 title claims abstract description 41
- 239000004208 shellac Substances 0.000 title claims abstract description 41
- 229940113147 shellac Drugs 0.000 title claims abstract description 41
- 235000013874 shellac Nutrition 0.000 title claims abstract description 41
- 239000000243 solution Substances 0.000 claims abstract description 158
- 229910052709 silver Inorganic materials 0.000 claims abstract description 71
- 239000004332 silver Substances 0.000 claims abstract description 71
- 239000000025 natural resin Substances 0.000 claims abstract description 70
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 59
- 229910021642 ultra pure water Inorganic materials 0.000 claims abstract description 35
- 239000012498 ultrapure water Substances 0.000 claims abstract description 35
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonium chloride Substances [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims abstract description 32
- PLKATZNSTYDYJW-UHFFFAOYSA-N azane silver Chemical compound N.[Ag] PLKATZNSTYDYJW-UHFFFAOYSA-N 0.000 claims abstract description 32
- 239000000758 substrate Substances 0.000 claims abstract description 23
- 238000011010 flushing procedure Methods 0.000 claims abstract description 21
- 238000010926 purge Methods 0.000 claims abstract description 20
- 238000003756 stirring Methods 0.000 claims abstract description 16
- 238000006243 chemical reaction Methods 0.000 claims abstract description 15
- 230000001603 reducing effect Effects 0.000 claims abstract description 12
- 238000005507 spraying Methods 0.000 claims abstract description 12
- 206010070834 Sensitisation Diseases 0.000 claims abstract description 10
- 230000008313 sensitization Effects 0.000 claims abstract description 10
- 239000010413 mother solution Substances 0.000 claims abstract description 8
- 239000011248 coating agent Substances 0.000 claims abstract description 7
- 238000000576 coating method Methods 0.000 claims abstract description 7
- 239000012670 alkaline solution Substances 0.000 claims abstract description 3
- 238000001035 drying Methods 0.000 claims abstract description 3
- 150000002576 ketones Chemical class 0.000 claims abstract description 3
- 238000002791 soaking Methods 0.000 claims abstract description 3
- 239000001856 Ethyl cellulose Substances 0.000 claims description 22
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 claims description 22
- 229920001249 ethyl cellulose Polymers 0.000 claims description 22
- 235000019325 ethyl cellulose Nutrition 0.000 claims description 22
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 claims description 17
- 239000008103 glucose Substances 0.000 claims description 17
- LJCNRYVRMXRIQR-OLXYHTOASA-L potassium sodium L-tartrate Chemical compound [Na+].[K+].[O-]C(=O)[C@H](O)[C@@H](O)C([O-])=O LJCNRYVRMXRIQR-OLXYHTOASA-L 0.000 claims description 17
- 235000011006 sodium potassium tartrate Nutrition 0.000 claims description 17
- 239000007787 solid Substances 0.000 claims description 15
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 claims description 13
- 229940074439 potassium sodium tartrate Drugs 0.000 claims description 13
- 239000000203 mixture Substances 0.000 claims description 5
- 239000001476 sodium potassium tartrate Substances 0.000 claims description 4
- 238000007654 immersion Methods 0.000 claims description 3
- 230000035484 reaction time Effects 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 abstract description 25
- 239000012452 mother liquor Substances 0.000 abstract description 16
- 239000000843 powder Substances 0.000 abstract description 11
- 230000000694 effects Effects 0.000 abstract description 7
- 239000011231 conductive filler Substances 0.000 abstract description 4
- 229910052751 metal Inorganic materials 0.000 abstract description 2
- 239000002184 metal Substances 0.000 abstract description 2
- 238000005406 washing Methods 0.000 abstract description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 33
- 235000011114 ammonium hydroxide Nutrition 0.000 description 27
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 18
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 18
- 239000002245 particle Substances 0.000 description 18
- 230000000052 comparative effect Effects 0.000 description 15
- 239000002131 composite material Substances 0.000 description 13
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 description 11
- 238000000498 ball milling Methods 0.000 description 11
- 101710134784 Agnoprotein Proteins 0.000 description 10
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 9
- 229910021529 ammonia Inorganic materials 0.000 description 9
- 230000008859 change Effects 0.000 description 9
- 238000002156 mixing Methods 0.000 description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 8
- 230000002378 acidificating effect Effects 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 8
- 238000007639 printing Methods 0.000 description 8
- 229920000178 Acrylic resin Polymers 0.000 description 7
- 239000004925 Acrylic resin Substances 0.000 description 7
- 238000004090 dissolution Methods 0.000 description 7
- 239000011347 resin Substances 0.000 description 7
- 229920005989 resin Polymers 0.000 description 7
- 238000001878 scanning electron micrograph Methods 0.000 description 7
- 238000007650 screen-printing Methods 0.000 description 7
- 238000002441 X-ray diffraction Methods 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 238000007747 plating Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 229920003002 synthetic resin Polymers 0.000 description 6
- 239000000057 synthetic resin Substances 0.000 description 6
- -1 silver ions Chemical class 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 238000007664 blowing Methods 0.000 description 4
- 239000003795 chemical substances by application Substances 0.000 description 4
- 239000004205 dimethyl polysiloxane Substances 0.000 description 4
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 4
- 239000000523 sample Substances 0.000 description 4
- 238000010345 tape casting Methods 0.000 description 4
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 235000021355 Stearic acid Nutrition 0.000 description 3
- 238000000089 atomic force micrograph Methods 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 3
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 3
- 239000002243 precursor Substances 0.000 description 3
- 238000006722 reduction reaction Methods 0.000 description 3
- 239000008117 stearic acid Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 2
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 2
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 2
- 230000001476 alcoholic effect Effects 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000003814 drug Substances 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 239000000806 elastomer Substances 0.000 description 2
- 235000013305 food Nutrition 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 239000002120 nanofilm Substances 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 238000010587 phase diagram Methods 0.000 description 2
- 230000001235 sensitizing effect Effects 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000009210 therapy by ultrasound Methods 0.000 description 2
- 238000007738 vacuum evaporation Methods 0.000 description 2
- 238000004383 yellowing Methods 0.000 description 2
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 description 1
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 description 1
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 description 1
- 239000005642 Oleic acid Substances 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 125000003368 amide group Chemical group 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- CJZGTCYPCWQAJB-UHFFFAOYSA-L calcium stearate Chemical compound [Ca+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CJZGTCYPCWQAJB-UHFFFAOYSA-L 0.000 description 1
- 239000008116 calcium stearate Substances 0.000 description 1
- 235000013539 calcium stearate Nutrition 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000005234 chemical deposition Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 239000012776 electronic material Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 235000019441 ethanol Nutrition 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 235000011389 fruit/vegetable juice Nutrition 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000000017 hydrogel Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 description 1
- 229920005749 polyurethane resin Polymers 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 229920000036 polyvinylpyrrolidone Polymers 0.000 description 1
- 239000001267 polyvinylpyrrolidone Substances 0.000 description 1
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000028327 secretion Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000009967 tasteless effect Effects 0.000 description 1
- 238000001757 thermogravimetry curve Methods 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 239000004846 water-soluble epoxy resin Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Landscapes
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention relates to the technical field of metal powder preparation, and discloses a method for preparing flake silver powder by using shellac, which comprises the following steps: step S1: preparing a natural resin sacrificial template: coating the prepared lac solution on a flexible substrate, and curing; step S2: hydrophilic and sensitization treatment; step S3: preparing a silver film: spraying silver-ammonia solution and reducing solution on a natural resin sacrificial template for reaction, purging, flushing a silver film with ultrapure water, and purging at high temperature to obtain a bright silver film; step S4: immersing a natural resin sacrificial template plated with a silver film into an alcohol solution, a ketone solution or an alkaline solution, and stirring to obtain a flaky silver powder mother solution; step S5: crushing the flake silver powder mother liquor by adopting ultrasonic waves, and soaking and washing by ethanol, centrifuging and drying to obtain the flake silver powder. The prepared flake silver powder has uniform morphology and is flake; the surface is flat; the residue is little, and the conductive filler can produce very good conductive effect.
Description
Technical Field
The invention relates to the technical field of metal powder preparation, in particular to a method for preparing flake silver powder by using lac.
Background
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Silver powder is used as a conductive phase and has important application in conductive slurry, and the flake silver powder can form surface-to-surface contact in the process of forming a conductive path, so that the silver powder has better conductive performance compared with silver powder with other morphologies.
In recent years, research on preparing nano silver powder using green resources is increasing. The currently reported green synthesis method of nano silver is mainly to extract substances with reducing property from plant resources to reduce silver ions. However, the composition and dosage of the extract are difficult to control, the morphology and the particle size of the prepared nano silver powder are difficult to control, and the yield is low, so that the nano silver powder cannot be used as conductive filler.
At present, the preparation of commercial flake silver powder is mainly carried out by a mechanical ball milling method, but the mechanical ball milling method has high energy consumption. When preparing flake silver powder by a mechanical ball milling method, stearic acid is generally used as a ball milling medium, so that the surface of the silver powder prepared by the ball milling method is covered with a stearic acid film, and the silver powder is suitable for being used in traditional conductive slurry. With the development of wearable electronic materials, the matrix used in the flexible conductive composite material is not an oily system, but is mostly a hydrophilic system such as hydrogel, silver powder prepared by a ball milling method usually needs to be treated to be used in the flexible conductive composite material, and the conductive performance cannot be well exerted.
The chemical reduction method and the template method are also reported to prepare the flake silver powder, but the existing chemical reduction method has the problems that the morphology of the silver powder is not easy to control, the additives are more, the types of residual substances on the surface of the silver powder are complex, the mass production cannot be realized and the like; the template method introduces a large amount of synthetic resin in the preparation process, has the problems of complex post-treatment, large waste liquid discharge, higher overall production power consumption cost and the like, and is not beneficial to the green development of industry.
The soluble resin commonly used in the silver powder preparation process comprises water-soluble epoxy resin, water-soluble polyurethane resin, water-soluble acrylic resin, polyvinyl alcohol and the like. However, hydrophilic groups such as carboxyl, hydroxyl, amino, amido and the like are additionally introduced into the water-soluble resin in the synthesis process, and the preparation process is complex, so that the cost of the water-soluble resin is higher than that of the water-insoluble resin; acrylic resin is taken as an example, and the selling price of the acrylic resin is 4-5 ten thousand yuan/ton. As in the prior art CN104148655a, a green production method of plate-like silver powder is disclosed, which uses a vacuum evaporation plating method to produce plate-like silver powder using a water-soluble resin, and then dissolves the water-soluble resin in water so that the silver powder is detached. However, according to common knowledge in the art, even the water-soluble resin has good water resistance after self-crosslinking film formation, and further cannot be dissolved by pure water, and organic solvents are still needed for dissolution, which poses a threat to the environment; in addition, the high silver loss rate exists in the vacuum evaporation coating process, so that the preparation cost of the silver powder is increased again.
Shellac, also called shellac, is a natural resin produced by the shellac through the conversion of the plant juice absorbed by the shellac and secretion, has the characteristics of strong cohesiveness, insulation, moisture resistance, good film forming property and the like, is nontoxic and tasteless, and is commonly used in industries such as paint, medicine, food, fruit fresh keeping and the like. The "green industry", like the "green products", is becoming increasingly popular. And the lac in China has the advantages of rich resources, low price, lower cost, more convenient acquisition and the like compared with synthetic resin.
Disclosure of Invention
The invention aims at: aiming at the problems of high cost, long degradation period and increased environmental pressure existing in the preparation of the flake silver powder by using the existing synthetic resin, the method for preparing the flake silver powder by using the lac is provided, green resources can be continuously regenerated, the preparation process is green and pollution-free, the cost is lower, and the prepared flake silver powder is uniform in thickness and surface.
The technical scheme of the invention is as follows:
a method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template: dissolving lac in ethanol to prepare a lac solution; then coating the lac solution on a flexible PET substrate, and curing at 25-50 ℃ for 5-20 min;
step S2: the natural resin sacrificial template is hydrophilized with Sodium Dodecyl Sulfate (SDS) solution. With SnCl 2 Sensitizing the sacrificial template by the solution;
step S3: preparing a silver film: preparing silver ammonia solution, spraying the silver ammonia solution and the reducing solution on a natural resin sacrificial template at the same time for reaction, uniformly purging by an air compressor, flushing a silver film by ultrapure water, and purging at a high temperature of 60-90 ℃ until the liquid on the surface of the silver film disappears, thereby obtaining a bright silver film on the natural resin sacrificial template;
step S4: immersing a natural resin sacrificial template plated with a silver film into an alcohol solution, a ketone solution or an alkaline solution, and stirring to obtain a flaky silver powder mother solution;
step S5: crushing the flake silver powder mother solution by adopting ultrasonic, and soaking in ethanol, centrifuging and drying to obtain the nanometer flake silver powder.
The coating means in step S1 is screen printing or knife coating.
Preferably, the curing temperature is 50℃and the curing time is 10 minutes.
Preferably, the alcoholic solution is e.g. ethanol, methanol.
The production of plate-like silver powder using shellac has the following advantages over synthetic resins:
(1) Shellac is a natural biological resource and can be continuously regenerated. The cost is lower, the production process almost has no emission and waste generation, and the production process is more environment-friendly.
(2) Shellac can be naturally degraded by breaking the carbon chain, and the synthetic resin for the preparation of flake silver powder reported so far requires a considerable time to degrade.
(3) Shellac is widely used as a coating agent in paints, medicines and foods due to its good film forming property. According to the invention, the natural resin sacrificial template with good film forming property of lac is prepared, and the silver nano film is guided to grow orderly on the natural resin sacrificial template, so that the preparation of the flake silver powder with uniform thickness and surface is realized.
In addition, after the high-temperature blowing step is added, the silver film obtained on the natural resin sacrificial template is brighter, so that the generation of speckles or strip-shaped flaws on the surface of the silver film is effectively reduced, and the subsequent blackening and yellowing of the silver film are prevented.
According to a preferred embodiment, the shellac solution in step S1 is prepared from shellac and ethylcellulose in ethanol, the solids content of the shellac solution being 15 wt%, the mass ratio of shellac to ethylcellulose being in the range of 9:1-7:3.
The lac solution coated on the PET substrate is solidified to form a lac film with a smooth surface, but the lac film is slowly dissolved under the action of the silver-ammonia solution and the reducing solution, so that the plated silver film layer is slightly uneven, and the quality of the prepared flake silver powder is reduced. After the ethylcellulose is added into the lac solution, the dissolution of the lac film is inhibited, so that the surface evenness of the lac film is further maintained, and the thickness uniformity of the prepared flaky silver powder is ensured.
Preferably, the mass ratio of lac to ethylcellulose is 7:3.
According to a preferred embodiment, in step S2, the concentration of the SDS solution is 0.35 mM; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
According to a preferred embodiment, in step S2, the hydrophilic treatment time is 5 minutes and the sensitizing treatment time is 5 minutes.
According to a preferred embodiment, in step S3, the reducing solution is one or a mixture of two of glucose and sodium potassium tartrate.
In step S3, when the reducing solution is a mixture of potassium sodium tartrate and glucose, the mass ratio of the reducing solution is as follows: 5:8-1:8. Preferably, it is: 1:7.
When the mass ratio of potassium sodium tartrate to glucose in the reducing solution is 1:8, the deposition speed of the silver film is too high, the flatness of the silver film can be reduced, and when the mass ratio is 5:8, the deposition speed of the silver film is too low, impurities are generated on the surface of the silver film, and the yellowing and blackening of the silver film affect the quality of the prepared flake silver powder. When the mass ratio of potassium sodium tartrate to glucose is 1:7, the deposition speed of the silver film is optimal, so that the surface evenness of the silver film can be ensured, and the quality of the flake silver powder can be ensured.
According to a preferred embodiment, in step S3, the reaction time for the reaction by spraying onto the sacrificial template of natural resin is between 5 and 8 minutes, preferably 6 minutes.
According to a preferred embodiment, in step S3, the silver-ammonia solution preparation method comprises the following steps: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution.
According to a preferred embodiment, in step S4, the natural resin sacrificial template coated with the silver film is immersed in an alcoholic solution of ethanol for 1 to 5 minutes, preferably 2 minutes, with a stirring speed of 500 to 1000 r/min, preferably 700 r/min.
The dissolution rate of the ultraviolet film can be controlled by controlling the immersion time and the stirring speed, and the slow dissolution of the ultraviolet film can prolong the dissolution time of the ultraviolet film, so that the problem that part of the ultraviolet film is adhered to the surface of the flake silver powder again in the dissolution process can exist. Through experiments, the applicant of the application finds that the dissolution rate of the ultraviolet film is most suitable under the condition that the stirring speed is 700 r/min and the immersion time is 2 minutes, and the prepared flaky silver film almost has no residue on the surface.
The ethanol has good eluting effect and less impurity residue, as shown in figure 5, and is environment-friendly and recyclable.
According to a preferred embodiment, in step S3, the temperature of the high temperature purge is preferably 80-85 ℃, more preferably 85 ℃.
According to a preferred embodiment, in step S5, the ultrasonic power is 480W, the ultrasonic time is 10-50 minutes, and the ultrasonic time can be adjusted according to the requirements of the particle size of the silver powder in the subsequent application.
The application also provides application of the lac in preparing flake silver powder.
Compared with the prior art, the invention has the beneficial effects that:
1. a method for preparing flake silver powder by using lac, wherein the surface of the flake silver powder prepared by using the lac is not covered by stearic acid, so that the flake silver powder can be well dispersed in a flexible matrix and has excellent conductivity. In the process for preparing the flake silver powder by using the natural resin, a shellac material is used as a plating base material, so that a powerful guarantee is provided for subsequent large-scale roll-to-roll continuous mass preparation. The mature chemical deposition technology used in the process also ensures the large-scale production of the silver nano film, and reduces the waste of silver;
2. a method for preparing flake silver powder by using lac utilizes good film forming property of the lac to prepare a smooth and flat natural resin sacrificial template, so that flake silver powder with uniform thickness and uniform surface is prepared, the size of the prepared flake silver powder is controllable by the preparation process, the surface is uniform, and the flake silver powder is suitable for playing a good conductive role in conductive filler;
3. the method for preparing the flake silver powder by using the lac replaces synthetic resin, so that the cost is saved in industry, the overall surface quality of the prepared silver powder can be improved, and the use scene of the silver powder is widened; in the environment, natural renewable resources are utilized, natural rapid degradation can be realized, the preparation process is simple to operate, and organic solvents such as acetone and the like are not needed, so that the pressure on the environment is avoided, and the method belongs to a real green process method for preparing the flake silver powder.
Drawings
FIG. 1 is a comparative SEM image of the plate-like silver powders (a), (b) prepared in example 1 of the present invention and commercial plate-like silver powders (c), (d); FIG. 1 (a) is a general morphology view of the plate-like silver powder produced according to the present invention, and FIG. 1 (b) is a side cross-sectional view of the plate-like silver powder produced according to the present invention; FIG. 1 (c) is a general morphology diagram of a commercial plate-like silver powder, and FIG. 1 (d) is a side interface diagram of a commercial plate-like silver powder;
FIG. 2 is a graph showing the comparison of the particle size distribution of the plate-like silver powder prepared in examples 1 to 5 of the present invention under different ultrasonic time periods;
FIG. 3 is an XRD pattern of the plate-like silver powder prepared in example 1 of the present invention;
FIG. 4 is an AFM image of the plate-like silver powder prepared in example 1 of the present invention;
FIG. 5 is a TGA graph of the plate-like silver powder prepared in example 1 of the present invention;
FIG. 6 is a graph showing the comparison of the effect of silver plating on a sacrificial template of natural resin prepared in examples 1, 2 and 5 of the present invention using different shellac and ethylcellulose;
FIG. 7 is a golden phase diagram of flake silver powder prepared at different purge temperatures in the present invention;
FIG. 8 is a graph showing the surface resistance of the plate-like silver powder prepared at different purge temperatures in the present invention;
FIG. 9 is an SEM image of the plate-like silver powder prepared in example 7 and comparative example 1 according to the present invention;
fig. 10 is an SEM image of the spherical silver powder prepared in comparative example 2 of the present invention;
fig. 11 is an SEM image of the plate-like silver powder prepared in comparative example 2 of the present invention.
Detailed Description
The examples set forth below are merely basic illustrations of the inventive concepts to facilitate a further understanding of the invention by those skilled in the art and are not intended to limit the scope of the invention. The methods used in this application are conventional, unless otherwise specified. Unless otherwise specified, all of the experimental materials used in the present application are commercially available. Commercial flake silver powder was purchased from Zhongyuxin shield alloy limited.
The features and capabilities of the present invention are described in further detail below in connection with examples.
Example 1
A method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in the mass ratio of 7:3 into an ethanol solution, and preparing the lac solution with the solid content of 15 wt percent;
step S1.2: printing the lac solution on a flexible PET substrate in a screen printing mode, and placing the flexible PET substrate in a 50 ℃ oven for curing for 10 min to form the natural resin sacrificial template.
Step S2:
step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into an acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 1:7 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and simultaneously, uniformly purging by an air compressor. After the reaction is carried out for 6 minutes, the bright silver film is obtained by flushing with ultrapure water for 3 times and then blowing with hot air at 85 ℃;
step S4: immersing the silver film obtained in the step S3.2 in ethanol solution for 2 minutes, and stirring at the speed of 700 r/min to obtain flake silver powder mother liquor;
step S5: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to 480W, and setting ultrasonic time to 20 minutes to obtain flake silver powder with average particle size of 12.5 mu m.
As can be seen from comparison of FIG. 1 (a) and FIG. 1 (c), the SEM image of the flake silver powder prepared in this example and the SEM image of commercial flake silver powder (purchased from Zhongxin shield alloy Co., ltd.) are shown in FIG. 1, the flake silver powder prepared in this example has a uniform morphology, is of a flake structure, has a relatively uniform particle size, has no lubricant layer covering the surface, has a non-uniform morphology, and has other morphologies in which silver powder is doped. As can be seen by comparing FIGS. 1 (b) and (d), the silver flake prepared according to the present invention has a uniform thickness of about 55nm; and the commercial flake silver powder has unclear side edges and uneven thickness.
The XRD pattern of the silver flake prepared in the embodiment is shown in fig. 3, and thus, the graph shows that one strong peak appears in the silver flake at 38.12 degrees, and four weak peaks appear at 44.40 degrees, 64.5 degrees, 77.40 degrees and 81.6 degrees respectively. These five diffraction peaks represent the (111), (200), (220), (311) and (222) crystal planes of the silver face-centered cubic structure, respectively. Besides the five diffraction peaks, the spectrum has no other diffraction peaks, which are completely matched with the diffraction peaks on the silver standard card, so that the powder prepared by the method is very pure silver powder. The strong diffraction peak of the sample at 38.12 degrees shows that the silver powder prepared by the method is in an ideal sheet structure from the other side surface.
The AFM image of the plate-like silver powder prepared in this example is shown in fig. 4, from which it can be seen that the surface of the plate-like silver powder prepared in the invention is relatively flat and has low roughness. This is advantageous for the subsequent preparation of the conductive composite material, and can form better surface-to-surface contact when constructing the conductive channel, thereby improving the transmission rate of electrons.
The TGA profile of the plate-like silver powder prepared in this example is shown in fig. 5, from which it can be seen that the mass loss of the silver plate is small, only 1.52wt% during the whole heating process, indicating that almost no other substances remain on the surface of the plate-like silver powder prepared in this way.
Example 2
A method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in an ethanol solution according to a mass ratio of 8:2, and preparing the lac solution with a solid content of 15 wt%;
step S1.2: printing the lac solution on a flexible PET substrate in a screen printing mode, and placing the flexible PET substrate in a 50 ℃ oven for curing for 10 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into an acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
in the step S3.2, potassium sodium tartrate and glucose with the mass ratio of 1:4 are dissolved in ultrapure water, and are sprayed onto a natural resin sacrificial template at the same time with silver-ammonia solution in the volume ratio of 1:1, and meanwhile, the natural resin sacrificial template is uniformly purged by an air compressor. After 7 minutes of reaction, the film was rinsed 3 times with ultrapure water and then purged with hot air at 90℃to obtain a bright silver film.
Step S4: the bright silver film obtained in the step 3.2 is immersed in NaOH solution at 50 ℃ and 1M for 10 minutes, and stirred at the speed of 500 r/min, so as to obtain flake silver powder mother liquor.
Step S5: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to be 480W, and setting ultrasonic time to be 40 minutes to obtain flake silver powder with average particle size of 9 mu m.
The SEM pattern, XRD pattern, AFM pattern and TGA pattern of the plate-like silver powder prepared in this example were similar to those of example 1.
Example 3
Example 3 is a further modification of example 1; a method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in the mass ratio of 7:3 into an ethanol solution, and preparing the lac solution with the solid content of 15 wt percent;
step S1.2: printing the lac solution on a flexible PET substrate in a screen printing mode, and placing the flexible PET substrate in a 50 ℃ oven for curing for 10 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into an acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 1:6.5 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and uniformly blowing by an air compressor. After 7 minutes of reaction, flushing with ultrapure water for 3 times, and then blowing with 80 ℃ hot air to obtain a bright silver film;
step S4: immersing the silver film obtained in the step S3.2 in ethanol solution for 2 minutes, and stirring at the speed of 600 r/min to obtain a flaky silver powder mother solution;
step S5: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to 480W, and setting ultrasonic time to 30 minutes to obtain flake silver powder with average particle size of 10 mu m.
SEM images, XRD images and AFM images of the plate-like silver powder prepared in this example were similar to those of example 1.
Example 4
Example 4 is a further modification of example 3; a method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in the mass ratio of 7:3 into an ethanol solution, and preparing the lac solution with the solid content of 15 wt percent;
step S1.2: printing the lac solution on a flexible PET substrate in a knife coating mode, and placing the substrate in a 50 ℃ oven for curing for 10 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into an acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2 is: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 5:8 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and uniformly purging by an air compressor. After the reaction for 6 minutes, the film was rinsed 3 times with ultrapure water and then purged with hot air at 85℃to obtain a bright silver film.
Step S4: immersing the silver film obtained in the step S3.2 into ethyl acetate solution for 2 minutes, and stirring at the speed of 900 r/min to obtain flaky silver powder mother liquor;
the step S5 is as follows: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to 480W, and setting ultrasonic time to 50 minutes to obtain flake silver powder with average particle size of 6 mu m.
The SEM pattern, XRD pattern, AFM pattern and TGA pattern of the plate-like silver powder prepared in this example were similar to those of example 1.
Example 5
A method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in the mass ratio of 9:1 into an ethanol solution, and preparing the lac solution with the solid content of 15 wt percent;
step S1.2: printing the lac solution on a flexible PET substrate in a knife coating mode, and placing the substrate in a baking oven at 40 ℃ for curing for 15 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into an acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2 is: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 1:7 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and simultaneously, uniformly purging by an air compressor. After the reaction for 6 minutes, the film was rinsed 3 times with ultrapure water and then purged with hot air at 60℃to obtain a bright silver film.
Step S4: immersing the silver film obtained in the step S3.2 in ethanol solution for 4 minutes, and stirring at the speed of 500 r/min to obtain flake silver powder mother liquor;
the step S5 is as follows: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to 480W, and setting ultrasonic time to 10 minutes to obtain flake silver powder with an average particle size of 13 mu m.
The SEM pattern, XRD pattern, AFM pattern and TGA pattern of the plate-like silver powder prepared in this example were similar to those of example 1.
Example 6
A method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in the mass ratio of 7:3 into an ethanol solution, and preparing the lac solution with the solid content of 15 wt percent;
step S1.2: printing the lac solution on a flexible PET substrate in a knife coating mode, and placing the substrate in a baking oven at 25 ℃ for curing for 20 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into an acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2 is: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 1:3 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and uniformly purging by an air compressor. After the reaction for 6 minutes, the film was rinsed 3 times with ultrapure water and then purged with hot air at 85℃to obtain a bright silver film.
Step S4: immersing the silver film obtained in the step S3.2 in an acetone solution for 2 minutes, and stirring at the speed of 1000 r/min to obtain a flaky silver powder mother solution;
the step S5 is as follows: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to be 480W, and setting ultrasonic time to be 40 minutes to obtain flake silver powder with average particle size of 9 mu m.
The SEM pattern, XRD pattern, AFM pattern and TGA pattern of the plate-like silver powder prepared in this example were similar to those of example 1.
Fig. 2 is a graph showing the particle size distribution of the silver flake prepared in examples 1 to 5 of the present invention, and it can be seen from fig. 2 that the particle size of the silver flake can be controlled by the ultrasonic time, and the particle size distribution of the silver flake shows a tendency to gradually decrease as the ultrasonic treatment time increases. When the ultrasonic treatment time is 50 minutes, the average particle size of the silver flakes is about 6 mu m.
FIG. 6 shows the effect of silver plating on a natural resin sacrificial template prepared from lac solution in different proportions of lac and ethylcellulose in examples 5, 2 and 1 of the present application; as shown in fig. 6, when the ratio of shellac to ethylcellulose is 9:1, the plating is not uniform enough, and the surface has little reflection effect; when the ratio of the lac to the ethyl cellulose is 8:2, the uniformity of the coating is improved, the surface has a certain reflection effect, but the surface of the coating is flawed. When the ratio of lac to ethyl cellulose is 7:3, the plating layer is very uniform, the silver film on the surface is very bright, the whole surface has a reflection effect, and the surface has no visible flaws and concave-convex, which indicates that when the ratio of lac to ethyl cellulose is 7:3, the prepared natural resin sacrificial template is most suitable for the uniform growth of the silver film on the natural resin sacrificial template, and the flat and bright silver film can be prepared by using the natural resin sacrificial template.
As shown in fig. 7, which is a golden phase diagram of the silver film obtained at 60 ℃, 70 ℃, 80 ℃, 85 ℃ and 90 ℃ purge temperature in the present application, as can be seen from fig. 7, the surface of the non-purged silver film has flaws, and the flaws on the surface of the silver film are reduced after purging. The silver film surface condition is best at temperatures of 85 ℃ and 90 ℃. As a result of performing surface resistance test on the silver film by using the four-probe tester, as shown in fig. 8, as can be seen from fig. 8, the surface resistance of the silver film which is not purged is higher, and as the purging temperature increases, the surface resistance of the silver film gradually decreases. After the temperature reaches 80 ℃, the surface resistance of the silver film reaches the minimum value and basically remains unchanged. It can be seen that the optimum purge temperature is 85 ℃.
Example 7
A method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in the mass ratio of 9:1 into an ethanol solution, and preparing the lac solution with the solid content of 15 wt percent;
step S1.2: printing the lac solution on a flexible PET substrate in a screen printing mode, and placing the flexible PET substrate in a baking oven at 25 ℃ for curing for 20 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 1:4 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and uniformly purging by an air compressor. After the reaction for 6 minutes, the film was rinsed 3 times with ultrapure water and then purged with hot air at 80℃to obtain a bright silver film.
Step S4: immersing the silver film obtained in the step S3.2 in ethanol solution for 5 minutes, and stirring at the speed of 500 r/min to obtain flake silver powder mother liquor;
step S5: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to 480W, and setting ultrasonic time to 10 minutes to obtain flake silver powder with an average particle size of 13 mu m.
Example 8
A method for preparing flake silver powder by using shellac, comprising the following steps:
step S1: preparing a natural resin sacrificial template:
step S1.1: preparing a lac solution, namely dissolving lac and ethyl cellulose in an ethanol solution according to a mass ratio of 8:2, and preparing the lac solution with a solid content of 15 wt%;
step S1.2: printing the lac solution on a flexible PET substrate in a screen printing mode, and placing the flexible PET substrate in a 30 ℃ oven for curing for 10 min to form the natural resin sacrificial template.
Step S2.1: hydrophilic treatment: placing the natural resin sacrificial template in 0.35 mM SDS solution, taking out after 5 min, and flushing with ultrapure water;
step S2.2: sensitization: placing the natural resin sacrificial template processed in the step S2.1 into acidic SnCl 2 Taking out the solution after 5 min, and flushing with ultrapure water; the SnCl 2 The solution was prepared from 10. 10 mL/L hydrochloric acid and 44.3mM SnCl 2 Mixing.
Step S3.1: the silver-ammonia solution is prepared according to the following preparation method: 28wt% ammonia was added dropwise to 58.8mM AgNO 3 In the solution, the solution was observed to change from transparent to turbid, and the dropwise addition was continued until the solution became transparent. At this time, the solution was again clouded by adding 1M NaOH solution, and then 28wt% ammonia water was added to obtain a transparent silver ammonia solution;
step S3.2: and (3) dissolving potassium sodium tartrate and glucose with the mass ratio of 1:3 into ultrapure water, spraying the solution and the silver ammonia solution onto the natural resin sacrificial template at the same time with the volume ratio of 1:1, and uniformly purging by an air compressor. After 5 minutes of reaction, the film was rinsed 3 times with ultrapure water and then purged with hot air at 85℃to obtain a bright silver film.
Step S4: the bright silver film obtained in the step 3.2 is immersed in NaOH solution at 50 ℃ and 1M for 10 minutes, and stirred at the speed of 500 r/min, so as to obtain flake silver powder mother liquor.
Step S5: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to be 480W, and setting ultrasonic time to be 40 minutes to obtain flake silver powder with average particle size of 9.1 mu m.
Step S6.1: 0.162g of the silver powder in S5, 0.164g of polydimethylsiloxane (main agent: curing agent=10:1) and 0.09 g of 4-methyl-2-pentanone were mechanically mixed for 30 min.
Step S6.2: a conductive elastomer film was deposited on a polydimethylsiloxane substrate through a mask and evacuated at-8 kPa for 20 minutes to eliminate bubbles and cured at 145 ℃ at 4 h to give a conductive composite with a solids content of 49.7 wt%.
Step S6.3: and (3) testing the conductive composite material obtained in the step S6.2 by a four-probe tester to obtain the conductive composite material with the conductivity of 9353.1S/cm.
Comparative example 1
This comparative example differs from example 7 in that:
step S1: preparation of an acrylic sacrificial template:
step S1.1: dissolving heat-shrinkable acrylic resin in cyclohexanone solution, and diluting to 15 wt%;
step S1.2: the diluted acrylic resin is printed on a flexible PET substrate in a screen printing mode, and is placed into an oven at 80 ℃ to be cured for 1 h, so that the acrylic resin sacrificial template is formed.
Step S4: immersing the silver film obtained in the step S3.2 into an acetone solution for 15 minutes to obtain a flaky silver powder mother solution;
step S5: and (3) placing the flake silver powder mother liquor into a high-energy ultrasonic pulverizer to pulverize, setting ultrasonic power to 480W, and setting ultrasonic time to 50 minutes to obtain flake silver powder with average particle size of 7.5 mu m.
The rest of the procedure was the same as in example 7.
SEM tests were performed on the silver powders prepared in example 7 and comparative example 1, and as a result, as shown in fig. 9, fig. 9a, 9b are the silver powders prepared in example 7, and fig. 9c, 9d are the silver powders prepared in comparative example 1. As can be seen from comparing fig. 9a, 9b and 9c, 9d, when the magnification is the same, the silver powder prepared in example 7 has smooth and flat surface, while the silver powder prepared in comparative example 1 has rough surface, uneven surface, and more remarkable after the comparison and magnification. The silver powder has large surface roughness and rugged surface, so that fluctuation of the thickness of the silver powder and uniformity reduction can be caused.
From the comparison of the material level used in example 7 and comparative example 1, it can be found that shellac, ethylcellulose and ethanol used in example 7 are all environment-friendly materials or reagents; in the corresponding process, reagents such as acrylic resin, acetone and the like are used in comparative example 1. The curing temperature was 25℃and the curing time was 20 min in example 7; in comparative example 1, the curing temperature was 80℃and the curing time was 1 h. Example 7 the curing using the oven was performed at a lower temperature and for a shorter time, and therefore less energy consuming.
Comparative example 2
The comparative example uses a mechanical ball milling method to prepare the plate-like silver powder.
Step S1: preparing spherical silver powder as a precursor:
step S1.1: weighing 4g of polyvinylpyrrolidone and dissolving in 200 ml glycol, adding 1g of AgNO 3 Fully stirring and dissolving to prepare a precursor solution;
step S1.2: transferring the precursor solution into a 500 ml flask, putting a magnet, putting into 160 ℃ oil bath, setting stirring speed to be 300 r/min, and reacting at constant temperature for 60min.
Step S1.3: the silver powder obtained after the reaction in the step S1.2 was washed three times with ethanol, centrifugally separated at a rotational speed of 8000 r/min, and vacuum-dried at 40℃for 3 h to obtain spherical silver powder, and the morphology thereof was SEM-tested, and the result is shown in FIG. 10.
Step S2.1: the stainless steel ball mill of 25 g was charged into a 100 ml ball mill pot, and 2.5 g spherical silver powder, 0.05 g calcium stearate, 0.05 ml oleic acid, and 3 ml ethanol were sequentially placed into the ball mill pot as ball milling media. Then closing the ball milling tank;
step S2.2: 2 ball milling tanks are directly opposite to and fixed on a ball mill, and ball milling is performed for 0.5h at a rotating speed of 50 r/min;
step S2.3: the ball mill rotational speed was reset to 250 r/min and ball milled 24 h.
Step S3: and (3) washing the ball-milled material in the step (2.3) with ethanol for 3 times. And (3) carrying out vacuum drying on 2 h at 50 ℃ to obtain flake silver powder with the particle size of 2-6 mu m, and carrying out SEM (scanning electron microscope) test on the morphology of the flake silver powder, wherein the result is shown in FIG. 11.
Step S4.1: 0.651 g of silver powder in S3, 0.202. 0.202 g polydimethylsiloxane (main agent: curing agent=10:1) and 0.20 g of 4-methyl-2-pentanone were mechanically mixed for 30 min.
Step S4.2: a conductive elastomer film was deposited on a polydimethylsiloxane substrate through a mask and evacuated at-8 kPa for 20 minutes to eliminate bubbles and cured at 145 ℃ at 4 h to give a conductive composite with a solids content of 76.2 wt%.
Step S4.3: and (3) testing the conductive composite material obtained in the step S4.2 by a four-probe tester to obtain the conductive composite material with the conductivity of 7486.3S/cm.
The comparison of the conductivity shows that: the conductivity of the conductive composite prepared in example 8 was as high as 9353.1S/cm at a silver powder solids content of 49.7 wt%, and the conductivity of the conductive composite prepared in comparative example 2 was 7486.3S/cm at a silver powder solids content of 76.2 wt%. It can be seen that the conductivity of the conductive composite material is greatly improved when the solid content of the silver powder prepared in example 8 of the present invention is reduced by about 34% wt%. It is known that the cost of the conductive composite material is mainly derived from the price of silver powder, and the use of the flake silver powder prepared by the method as the conductive filler can improve the conductive performance and reduce the production cost by about 34 percent.
The foregoing examples merely represent specific embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the present application. It should be noted that, for those skilled in the art, several variations and modifications can be made without departing from the technical solution of the present application, which fall within the protection scope of the present application.
Claims (10)
1. A method for preparing flake silver powder by using lac, which is characterized by comprising the following steps:
step S1: preparing a natural resin sacrificial template: dissolving lac in ethanol to prepare a lac solution; coating the lac solution on a flexible substrate, and curing;
step S2: carrying out hydrophilic treatment and sensitization treatment on the natural resin sacrificial template;
step S3: preparing a silver film: preparing silver-ammonia solution, spraying the silver-ammonia solution and the reducing solution on a natural resin sacrificial template simultaneously for reaction, uniformly purging, flushing a silver film with ultrapure water, and purging at a high temperature of 60-90 ℃ to obtain a bright silver film on the natural resin sacrificial template;
step S4: immersing a natural resin sacrificial template plated with a silver film into an alcohol solution, a ketone solution or an alkaline solution, and stirring to obtain a flaky silver powder mother solution;
step S5: crushing the silver flake mother solution by adopting ultrasonic, and soaking in ethanol, centrifuging and drying to obtain the silver flake.
2. The method for preparing flake silver powder by using shellac according to claim 1, wherein the shellac solution in the step S1 is prepared by dissolving shellac and ethyl cellulose in ethanol, the solid content of the shellac solution is 15 wt%, and the mass ratio of shellac to ethyl cellulose is 9:1-7:3.
3. The method for preparing plate-like silver powder using shellac according to claim 2, wherein the mass ratio of shellac to ethylcellulose is 7:3.
4. The method for preparing flake silver powder by using shellac according to claim 1, wherein in the step S3, the reducing solution is one or two of glucose and sodium potassium tartrate, and when the reducing solution is a mixture of sodium potassium tartrate and glucose, the mass ratio of sodium potassium tartrate to glucose is: 5:8-1:8.
5. The method for preparing flake silver powder by using shellac according to claim 4, wherein in the step S3, when the reducing solution is a mixture of potassium sodium tartrate and glucose, the mass ratio of potassium sodium tartrate to glucose is: 1:7.
6. The method for preparing plate-like silver powder using shellac according to claim 1, wherein the reaction time for spraying onto the natural resin sacrificial template for the reaction in step S3 is 5 to 8 minutes.
7. The method for preparing plate-like silver powder using shellac according to claim 1, wherein in step S4, the natural resin sacrificial template coated with the silver film is immersed in an ethanol solution for 1 to 5 minutes with a stirring speed of 500 to 1000 r/min.
8. The method for preparing plate-like silver powder using shellac according to claim 7, wherein the immersion time of the natural resin sacrificial template coated with the silver film in the ethanol solution is 2 minutes and the stirring speed is 700 r/min in step S4.
9. The method for preparing plate-like silver powder using shellac according to claim 1, wherein the high-temperature purging is performed at 80 to 85 ℃ in step S3.
10. The application of lac in preparing flake silver powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410269899.0A CN117862520B (en) | 2024-03-11 | 2024-03-11 | Method for preparing flake silver powder by using shellac |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410269899.0A CN117862520B (en) | 2024-03-11 | 2024-03-11 | Method for preparing flake silver powder by using shellac |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117862520A true CN117862520A (en) | 2024-04-12 |
| CN117862520B CN117862520B (en) | 2024-05-10 |
Family
ID=90593306
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410269899.0A Active CN117862520B (en) | 2024-03-11 | 2024-03-11 | Method for preparing flake silver powder by using shellac |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117862520B (en) |
Citations (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007043664A1 (en) * | 2005-10-14 | 2007-04-19 | Toyo Ink Mfg. Co., Ltd. | Method for producing metal particle dispersion, conductive ink using metal particle dispersion produced by such method, and conductive coating film |
| CN101569936A (en) * | 2009-06-05 | 2009-11-04 | 中国乐凯胶片集团公司 | Preparation method for flaky micro-aluminum powder |
| WO2010024256A1 (en) * | 2008-08-25 | 2010-03-04 | 日本板硝子株式会社 | Silver-based photoluminescent pigment and a cosmetic composition, paint composition, adiabatic paint composition, ink composition, and resin composition containing same |
| JP2011208278A (en) * | 2010-03-10 | 2011-10-20 | Dowa Holdings Co Ltd | Flaky silver powder and method for producing the same |
| CN102974839A (en) * | 2012-12-04 | 2013-03-20 | 中山大学 | Method for preparing nanometer flake silver powder through chemical deposition |
| CN103480838A (en) * | 2013-10-16 | 2014-01-01 | 哈尔滨工业大学 | Preparation method of nano silver-coated copper powder |
| CN104148655A (en) * | 2014-07-14 | 2014-11-19 | 中山大学 | Environment-friendly flake silver powder preparation method |
| CN105236760A (en) * | 2015-11-02 | 2016-01-13 | 云南师范大学 | Method for manufacturing mirror by using coated flaky aluminum powder |
| JP2016035098A (en) * | 2014-07-31 | 2016-03-17 | Ｄｏｗａエレクトロニクス株式会社 | Silver-coated flake type copper powder and production method of the same, and conductive paste using the silver-coated flake type copper powder |
| JP2017002409A (en) * | 2014-07-31 | 2017-01-05 | Ｄｏｗａエレクトロニクス株式会社 | Silver powder and manufacturing method therefor |
| CN106573300A (en) * | 2014-07-31 | 2017-04-19 | 同和电子科技有限公司 | Silver powder, method for producing same, and conductive paste |
| CN106573301A (en) * | 2014-07-31 | 2017-04-19 | 同和电子科技有限公司 | Silver powder, method for producing same, and conductive paste |
| JP2017101268A (en) * | 2015-11-30 | 2017-06-08 | Ｄｏｗａエレクトロニクス株式会社 | Spherical silver powder and manufacturing method and conductive paste |
| CN108580920A (en) * | 2018-03-16 | 2018-09-28 | 南京林业大学 | A kind of preparation method of flake silver powder |
| CN109663932A (en) * | 2018-03-16 | 2019-04-23 | 南京林业大学 | A kind of preparation method of flake silver powder |
| CN110832040A (en) * | 2017-05-15 | 2020-02-21 | 巴斯夫欧洲公司 | Method for producing a metal nanoparticle layer and use thereof in decorative or security elements |
| CN112912191A (en) * | 2018-10-25 | 2021-06-04 | 巴斯夫欧洲公司 | Compositions comprising silver nanoplatelets |
| CN113677458A (en) * | 2019-03-29 | 2021-11-19 | 大洲电子材料株式会社 | Mixed silver powder and conductive paste containing the same |
| CN113811409A (en) * | 2019-05-06 | 2021-12-17 | 巴斯夫欧洲公司 | Compositions comprising silver nanoplates |
| CN114255906A (en) * | 2015-12-09 | 2022-03-29 | C3内诺公司 | Method for synthesizing silver nanoplates and noble metal coated silver nanoplates, and use thereof in transparent films |
| WO2022167377A1 (en) * | 2021-02-03 | 2022-08-11 | Basf Se | Compositions, comprising silver nanoplatelets |
-
2024
- 2024-03-11 CN CN202410269899.0A patent/CN117862520B/en active Active
Patent Citations (22)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007043664A1 (en) * | 2005-10-14 | 2007-04-19 | Toyo Ink Mfg. Co., Ltd. | Method for producing metal particle dispersion, conductive ink using metal particle dispersion produced by such method, and conductive coating film |
| WO2010024256A1 (en) * | 2008-08-25 | 2010-03-04 | 日本板硝子株式会社 | Silver-based photoluminescent pigment and a cosmetic composition, paint composition, adiabatic paint composition, ink composition, and resin composition containing same |
| CN101569936A (en) * | 2009-06-05 | 2009-11-04 | 中国乐凯胶片集团公司 | Preparation method for flaky micro-aluminum powder |
| JP2011208278A (en) * | 2010-03-10 | 2011-10-20 | Dowa Holdings Co Ltd | Flaky silver powder and method for producing the same |
| CN102974839A (en) * | 2012-12-04 | 2013-03-20 | 中山大学 | Method for preparing nanometer flake silver powder through chemical deposition |
| CN103480838A (en) * | 2013-10-16 | 2014-01-01 | 哈尔滨工业大学 | Preparation method of nano silver-coated copper powder |
| CN104148655A (en) * | 2014-07-14 | 2014-11-19 | 中山大学 | Environment-friendly flake silver powder preparation method |
| CN106573300A (en) * | 2014-07-31 | 2017-04-19 | 同和电子科技有限公司 | Silver powder, method for producing same, and conductive paste |
| JP2017002409A (en) * | 2014-07-31 | 2017-01-05 | Ｄｏｗａエレクトロニクス株式会社 | Silver powder and manufacturing method therefor |
| CN106573301A (en) * | 2014-07-31 | 2017-04-19 | 同和电子科技有限公司 | Silver powder, method for producing same, and conductive paste |
| JP2016035098A (en) * | 2014-07-31 | 2016-03-17 | Ｄｏｗａエレクトロニクス株式会社 | Silver-coated flake type copper powder and production method of the same, and conductive paste using the silver-coated flake type copper powder |
| CN105236760A (en) * | 2015-11-02 | 2016-01-13 | 云南师范大学 | Method for manufacturing mirror by using coated flaky aluminum powder |
| JP2017101268A (en) * | 2015-11-30 | 2017-06-08 | Ｄｏｗａエレクトロニクス株式会社 | Spherical silver powder and manufacturing method and conductive paste |
| CN114255906A (en) * | 2015-12-09 | 2022-03-29 | C3内诺公司 | Method for synthesizing silver nanoplates and noble metal coated silver nanoplates, and use thereof in transparent films |
| CN110832040A (en) * | 2017-05-15 | 2020-02-21 | 巴斯夫欧洲公司 | Method for producing a metal nanoparticle layer and use thereof in decorative or security elements |
| CN109663932A (en) * | 2018-03-16 | 2019-04-23 | 南京林业大学 | A kind of preparation method of flake silver powder |
| CN108580920A (en) * | 2018-03-16 | 2018-09-28 | 南京林业大学 | A kind of preparation method of flake silver powder |
| CN112912191A (en) * | 2018-10-25 | 2021-06-04 | 巴斯夫欧洲公司 | Compositions comprising silver nanoplatelets |
| CN113677458A (en) * | 2019-03-29 | 2021-11-19 | 大洲电子材料株式会社 | Mixed silver powder and conductive paste containing the same |
| CN113811409A (en) * | 2019-05-06 | 2021-12-17 | 巴斯夫欧洲公司 | Compositions comprising silver nanoplates |
| WO2022167377A1 (en) * | 2021-02-03 | 2022-08-11 | Basf Se | Compositions, comprising silver nanoplatelets |
| CN117203007A (en) * | 2021-02-03 | 2023-12-08 | 巴斯夫欧洲公司 | Composition comprising silver nanoplates |
Non-Patent Citations (2)
| Title |
|---|
| JUN WANG: ""flaky silver powders prepared with nanofilm transition method: application for printable electronics"", JOURNAL OF METERIALS CHEMISTRY C, no. 1, 16 October 2012 (2012-10-16), pages 230 - 233 * |
| 刘朋;文明芬;: "超细银粉的制备及其粒径表征的研究", 中国粉体工业, no. 02, 25 April 2010 (2010-04-25) * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117862520B (en) | 2024-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102424568B (en) | Method for preparing tungsten-containing alumina ceramic heating substrate | |
| CN112570728B (en) | Flake silver powder and preparation method and application thereof | |
| CN108728835A (en) | A kind of preparation method of electroplate material | |
| CN111992736A (en) | Preparation method of silver nanoparticles | |
| CN110369712B (en) | Preparation method of silver-coated copper powder | |
| CN110808369B (en) | Preparation method of low-sodium-sulfur nickel-cobalt-aluminum ternary precursor | |
| CN114054769B (en) | Silver micro powder and preparation method and application thereof | |
| CN107325787A (en) | A kind of hollow carbon nano-particle and the absorbing material prepared by it | |
| CN111905796A (en) | Preparation method of superfine metal nanoparticle/carbon nitride nanosheet composite material | |
| CN117862520B (en) | Method for preparing flake silver powder by using shellac | |
| CN114700490A (en) | Preparation method of nickel-coated graphite composite particles and application of nickel-coated graphite composite particles in electromagnetic shielding field | |
| CN114180644A (en) | Aluminum-doped cobalt carbonate material, preparation method thereof, aluminum-doped cobaltosic oxide and lithium cobaltate cathode material | |
| CN112853315A (en) | Surface modification method of solar front silver paste silver powder | |
| FR3139816A1 (en) | COBALT CARBONATE PRECURSOR CO-DOPED WITH ALUMINUM AND NICKEL, ITS PREPARATION METHOD AND ITS USE | |
| CN111646493A (en) | Hydrothermal preparation method of yttrium oxide nano powder | |
| CN115490273B (en) | Method for continuously preparing ternary precursor with large specific surface and prepared precursor | |
| CN110993927A (en) | Method for coating Al and Sm on high-nickel ternary material by washing | |
| CN111659901A (en) | Preparation method of submicron silver powder | |
| CN112982022B (en) | Preparation method of copper-plated reduced graphene oxide wave-absorbing paper | |
| CN113604778B (en) | AZO target material applied to solar cell and preparation method thereof | |
| CN112846213B (en) | Preparation method of low-oxygen high-dispersion nano spherical cobalt powder | |
| CN115448382A (en) | High-nickel ternary precursor and preparation method and application thereof | |
| CN108723384A (en) | A kind of preparation method of copper-containing wastewater recycling copper nanoparticle | |
| CN115184112A (en) | Preparation method of osmium target material microstructure sample | |
| CN107740145A (en) | A kind of highly conductive carbon pores liquid of pcb board and its preparation method and application |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |