JP2006161081A - Silvered copper powder, its manufacturing method, and conductive paste - Google Patents
Silvered copper powder, its manufacturing method, and conductive paste Download PDFInfo
- Publication number
- JP2006161081A JP2006161081A JP2004352024A JP2004352024A JP2006161081A JP 2006161081 A JP2006161081 A JP 2006161081A JP 2004352024 A JP2004352024 A JP 2004352024A JP 2004352024 A JP2004352024 A JP 2004352024A JP 2006161081 A JP2006161081 A JP 2006161081A
- Authority
- JP
- Japan
- Prior art keywords
- silver
- copper powder
- coated
- average thickness
- value
- 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
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 178
- 238000004519 manufacturing process Methods 0.000 title claims description 15
- 229910052709 silver Inorganic materials 0.000 claims abstract description 211
- 239000004332 silver Substances 0.000 claims abstract description 211
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 198
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims abstract description 76
- 239000002245 particle Substances 0.000 claims abstract description 50
- 229910001961 silver nitrate Inorganic materials 0.000 claims abstract description 38
- 239000003960 organic solvent Substances 0.000 claims abstract description 37
- 229910052802 copper Inorganic materials 0.000 claims abstract description 19
- 239000010949 copper Substances 0.000 claims abstract description 19
- 239000000839 emulsion Substances 0.000 claims abstract description 18
- 239000000945 filler Substances 0.000 claims abstract description 16
- -1 silver ions Chemical class 0.000 claims abstract description 16
- 238000006467 substitution reaction Methods 0.000 claims abstract description 13
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000003125 aqueous solvent Substances 0.000 claims abstract description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 5
- FOIXSVOLVBLSDH-UHFFFAOYSA-N Silver ion Chemical compound [Ag+] FOIXSVOLVBLSDH-UHFFFAOYSA-N 0.000 claims abstract description 4
- 150000001299 aldehydes Chemical class 0.000 claims abstract description 4
- 150000002576 ketones Chemical class 0.000 claims abstract description 4
- 238000000576 coating method Methods 0.000 claims description 64
- 239000011248 coating agent Substances 0.000 claims description 63
- 239000011247 coating layer Substances 0.000 claims description 31
- 238000000034 method Methods 0.000 claims description 25
- 238000009826 distribution Methods 0.000 claims description 17
- 239000007788 liquid Substances 0.000 claims description 13
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 11
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 11
- 229910052799 carbon Inorganic materials 0.000 claims description 11
- 239000001301 oxygen Substances 0.000 claims description 11
- 229910052760 oxygen Inorganic materials 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 6
- 239000002738 chelating agent Substances 0.000 claims description 5
- 230000009467 reduction Effects 0.000 claims description 5
- 238000007561 laser diffraction method Methods 0.000 claims description 3
- 238000004438 BET method Methods 0.000 claims description 2
- 239000006174 pH buffer Substances 0.000 claims description 2
- 230000002209 hydrophobic effect Effects 0.000 abstract description 5
- 239000002184 metal Substances 0.000 abstract description 5
- 229910052751 metal Inorganic materials 0.000 abstract description 5
- GGCZERPQGJTIQP-UHFFFAOYSA-N sodium;9,10-dioxoanthracene-2-sulfonic acid Chemical compound [Na+].C1=CC=C2C(=O)C3=CC(S(=O)(=O)O)=CC=C3C(=O)C2=C1 GGCZERPQGJTIQP-UHFFFAOYSA-N 0.000 abstract description 4
- 239000000126 substance Substances 0.000 abstract description 4
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 48
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 41
- 239000000243 solution Substances 0.000 description 34
- 238000006243 chemical reaction Methods 0.000 description 25
- 238000003756 stirring Methods 0.000 description 16
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 15
- 239000002994 raw material Substances 0.000 description 15
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 14
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 description 13
- 239000001099 ammonium carbonate Substances 0.000 description 13
- 239000012752 auxiliary agent Substances 0.000 description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 12
- 235000012501 ammonium carbonate Nutrition 0.000 description 12
- 239000006185 dispersion Substances 0.000 description 12
- 239000007864 aqueous solution Substances 0.000 description 11
- 239000012071 phase Substances 0.000 description 11
- 239000000843 powder Substances 0.000 description 8
- 239000012066 reaction slurry Substances 0.000 description 8
- 239000004094 surface-active agent Substances 0.000 description 8
- 238000005406 washing Methods 0.000 description 8
- 235000021355 Stearic acid Nutrition 0.000 description 7
- 238000005238 degreasing Methods 0.000 description 7
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 7
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 7
- 230000008569 process Effects 0.000 description 7
- 239000008117 stearic acid Substances 0.000 description 7
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 6
- 229910052757 nitrogen Inorganic materials 0.000 description 6
- 150000003839 salts Chemical class 0.000 description 6
- OVBJJZOQPCKUOR-UHFFFAOYSA-L EDTA disodium salt dihydrate Chemical compound O.O.[Na+].[Na+].[O-]C(=O)C[NH+](CC([O-])=O)CC[NH+](CC([O-])=O)CC([O-])=O OVBJJZOQPCKUOR-UHFFFAOYSA-L 0.000 description 5
- 239000008346 aqueous phase Substances 0.000 description 5
- 238000001816 cooling Methods 0.000 description 5
- 230000006866 deterioration Effects 0.000 description 5
- 239000011259 mixed solution Substances 0.000 description 5
- 238000006722 reduction reaction Methods 0.000 description 5
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 4
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 4
- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 description 4
- 235000014113 dietary fatty acids Nutrition 0.000 description 4
- 229930195729 fatty acid Natural products 0.000 description 4
- 239000000194 fatty acid Substances 0.000 description 4
- 150000004665 fatty acids Chemical class 0.000 description 4
- 230000005484 gravity Effects 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 150000003378 silver Chemical class 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- 230000014759 maintenance of location Effects 0.000 description 3
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 238000010301 surface-oxidation reaction Methods 0.000 description 3
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 150000001298 alcohols Chemical class 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- 239000012298 atmosphere Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 239000011231 conductive filler Substances 0.000 description 2
- 229910001431 copper ion Inorganic materials 0.000 description 2
- 150000002170 ethers Chemical class 0.000 description 2
- 238000005187 foaming Methods 0.000 description 2
- 235000011187 glycerol Nutrition 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- ZXEKIIBDNHEJCQ-UHFFFAOYSA-N isobutanol Chemical compound CC(C)CO ZXEKIIBDNHEJCQ-UHFFFAOYSA-N 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000006179 pH buffering agent Substances 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- IMNIMPAHZVJRPE-UHFFFAOYSA-N triethylenediamine Chemical compound C1CN2CCN1CC2 IMNIMPAHZVJRPE-UHFFFAOYSA-N 0.000 description 2
- OAYXUHPQHDHDDZ-UHFFFAOYSA-N 2-(2-butoxyethoxy)ethanol Chemical compound CCCCOCCOCCO OAYXUHPQHDHDDZ-UHFFFAOYSA-N 0.000 description 1
- SBASXUCJHJRPEV-UHFFFAOYSA-N 2-(2-methoxyethoxy)ethanol Chemical compound COCCOCCO SBASXUCJHJRPEV-UHFFFAOYSA-N 0.000 description 1
- XNWFRZJHXBZDAG-UHFFFAOYSA-N 2-METHOXYETHANOL Chemical compound COCCO XNWFRZJHXBZDAG-UHFFFAOYSA-N 0.000 description 1
- POAOYUHQDCAZBD-UHFFFAOYSA-N 2-butoxyethanol Chemical compound CCCCOCCO POAOYUHQDCAZBD-UHFFFAOYSA-N 0.000 description 1
- ZNQVEEAIQZEUHB-UHFFFAOYSA-N 2-ethoxyethanol Chemical compound CCOCCO ZNQVEEAIQZEUHB-UHFFFAOYSA-N 0.000 description 1
- 229910000013 Ammonium bicarbonate Inorganic materials 0.000 description 1
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 239000005751 Copper oxide Substances 0.000 description 1
- RPNUMPOLZDHAAY-UHFFFAOYSA-N Diethylenetriamine Chemical compound NCCNCCN RPNUMPOLZDHAAY-UHFFFAOYSA-N 0.000 description 1
- LCGLNKUTAGEVQW-UHFFFAOYSA-N Dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 description 1
- QZKRHPLGUJDVAR-UHFFFAOYSA-K EDTA trisodium salt Chemical compound [Na+].[Na+].[Na+].OC(=O)CN(CC([O-])=O)CCN(CC([O-])=O)CC([O-])=O QZKRHPLGUJDVAR-UHFFFAOYSA-K 0.000 description 1
- XOBKSJJDNFUZPF-UHFFFAOYSA-N Methoxyethane Chemical compound CCOC XOBKSJJDNFUZPF-UHFFFAOYSA-N 0.000 description 1
- IKHGUXGNUITLKF-XPULMUKRSA-N acetaldehyde Chemical compound [14CH]([14CH3])=O IKHGUXGNUITLKF-XPULMUKRSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- WUOACPNHFRMFPN-UHFFFAOYSA-N alpha-terpineol Chemical compound CC1=CCC(C(C)(C)O)CC1 WUOACPNHFRMFPN-UHFFFAOYSA-N 0.000 description 1
- 235000012538 ammonium bicarbonate Nutrition 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- 238000000889 atomisation Methods 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 229910000431 copper oxide Inorganic materials 0.000 description 1
- SQIFACVGCPWBQZ-UHFFFAOYSA-N delta-terpineol Natural products CC(C)(O)C1CCC(=C)CC1 SQIFACVGCPWBQZ-UHFFFAOYSA-N 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 230000005661 hydrophobic surface Effects 0.000 description 1
- NBZBKCUXIYYUSX-UHFFFAOYSA-N iminodiacetic acid Chemical compound OC(=O)CNCC(O)=O NBZBKCUXIYYUSX-UHFFFAOYSA-N 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000008235 industrial water Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000000518 rheometry Methods 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 150000005846 sugar alcohols Polymers 0.000 description 1
- 229940116411 terpineol Drugs 0.000 description 1
- ZIBGPFATKBEMQZ-UHFFFAOYSA-N triethylene glycol Chemical compound OCCOCCOCCO ZIBGPFATKBEMQZ-UHFFFAOYSA-N 0.000 description 1
Images
Abstract
Description
本発明は、導電性ペースト等の用途に適した銀被覆銅粉およびその製造方法、並びにその銀被覆銅粉を使用した導電ペーストに関する。 The present invention relates to a silver-coated copper powder suitable for applications such as a conductive paste, a method for producing the same, and a conductive paste using the silver-coated copper powder.
導電ペーストは、実験目的から電子産業用途に至るまで幅広い分野で使用されている。中でも、高い電気伝導性が要求される用途においては、銀粉を導電フィラーとして使用した「銀系ペースト」が主として使用されている。しかし、「銀系ペースト」は銅粉を導電フィラーとして使用した「銅系ペースト」と比較し、i) 地金価格が高いため高価である、ii) マイグレーションが起こりやすい、iii) ハンダ食われ性が劣る、といった欠点を有している。これら欠点を克服する手法の一つとして、銀被覆銅粉が提案されている。 Conductive pastes are used in a wide range of fields, from experimental purposes to electronics industry applications. In particular, in applications that require high electrical conductivity, “silver-based paste” using silver powder as a conductive filler is mainly used. However, compared with “copper paste” using copper powder as a conductive filler, “silver paste” is expensive because of high metal prices, ii) easy to migrate, and iii) solder erosion Is inferior. As one method for overcoming these drawbacks, silver-coated copper powder has been proposed.
銀被覆銅粉の製造方法には、銅と銀の置換反応を利用とした置換法や、還元剤を用いた還元法がある。
特許文献１には、硝酸銀、炭酸アンモニウム塩及びＥＤＴＡ（エチレンジアミン四酢酸）三ナトリウムの銀錯塩溶液を用いて金属銅粉の表面に金属銀を析出させる方法が開示されている。
特許文献２には、硝酸銀、アンモニア水及びＥＤＴＡの銀錯塩溶液を用いて金属銅粉の表面に金属銀を析出させる方法が示されている。
特許文献３には、キレート化剤溶液に銅粉を分散させた後、分散液に銀イオン溶液を加えて還元反応を促し、さらに還元剤を添加して完全に還元析出させて、銅粉の表面に銀被膜を析出させる方法が開示されている。
As a method for producing silver-coated copper powder, there are a substitution method using a substitution reaction of copper and silver and a reduction method using a reducing agent.
Patent Document 1 discloses a method of depositing metallic silver on the surface of metallic copper powder using a silver complex solution of silver nitrate, ammonium carbonate and trisodium EDTA (ethylenediaminetetraacetic acid).
Patent Document 2 discloses a method of depositing metallic silver on the surface of metallic copper powder using a silver complex solution of silver nitrate, aqueous ammonia and EDTA.
In Patent Document 3, after copper powder is dispersed in a chelating agent solution, a silver ion solution is added to the dispersion to promote a reduction reaction, and a reducing agent is further added to completely reduce and precipitate the copper powder. A method for depositing a silver coating on the surface is disclosed.
しかし、これらはいずれも水溶液中での反応を利用するものであり、水溶媒中での銅粉の分散性を確保する観点から、脂肪酸等の疎水性の表面処理が施された銅粉、あるいは界面活性剤等の発泡性の表面処理が施された銅粉を、そのまま銀被覆反応に供することは困難である。したがって、一般的に入手しやすいこれらの銅粉を使用するには予め前処理を施して分散性を確保する必要があり、工程増による製造コストの増大を招く。 However, these all utilize a reaction in an aqueous solution, and from the viewpoint of ensuring the dispersibility of the copper powder in an aqueous solvent, a copper powder that has been subjected to a hydrophobic surface treatment such as fatty acid, or It is difficult to subject the copper powder subjected to foaming surface treatment such as a surfactant to the silver coating reaction as it is. Therefore, in order to use these copper powders that are generally easily available, it is necessary to pre-treat them in advance to ensure dispersibility, resulting in an increase in manufacturing cost due to an increase in the number of processes.
ところで、導電ペーストで用いるフィラー形状には、球状のものとフレーク状のものとがあり、通常は、球状のものとフレーク状のものを組み合わせて使用することが多い。球状のものは、粘度の低減、ペーストを硬化または焼結させた際の密度向上等に寄与し、フレーク状のものは、粘性（チキソ性）の調整、塗布性等の調整、嵩密度の抑制等に必要とされる。このうちフレーク状のものとしては、導電ペーストとして安定した粘度を持ち、適度な塗布性を持たせるために、粒径・厚みが均一であるものが望ましい。特に、ペーストの焼結性や接着強度を低減させるためには、粒径・厚みの揃ったフレーク状フィラーは不可欠である。また、電極として優れた導電性を有するためには、フレーク状フィラー中の不純物量が少ないことが望ましい。 By the way, the filler shape used in the conductive paste includes a spherical shape and a flake shape, and usually a combination of a spherical shape and a flake shape is often used. The spherical one contributes to the reduction of viscosity and the density improvement when the paste is cured or sintered, and the flaky one adjusts the viscosity (thixotropy), the applicability, etc., and suppresses the bulk density. Required for etc. Of these, the flakes are preferably those having a uniform viscosity and a uniform particle size and thickness in order to have a stable viscosity as a conductive paste and appropriate coating properties. In particular, in order to reduce paste sinterability and adhesive strength, a flaky filler having a uniform particle size and thickness is indispensable. In order to have excellent conductivity as an electrode, it is desirable that the amount of impurities in the flake filler is small.
フレーク状フィラーに要求されるこれらの特性は、銀被覆銅粉をフィラーとして使用した場合についても当てはまることである。しかしながら、銀被覆フレーク銅粉に関する銀被覆の均一性や、粒径・厚みを揃えることについては、未だ十分に研究がなされていない。 These properties required for the flaky filler are also applicable when silver-coated copper powder is used as the filler. However, sufficient research has not yet been conducted on the uniformity of the silver coating on the silver-coated flake copper powder and the uniforming of the particle size and thickness.
特許文献４には、アトマイズ粉を原料とし、助剤としてのステアリン酸を混合して偏平化することによりフレーク状銅粉を製造し、得られたフレーク状銅粉を脱脂・水洗後、銀被覆反応をすることにより銀被覆フレーク状銅粉を作製することが記載されている。この場合、銀被覆の効果は認められるものの、製造工程中の脱脂・水洗処理が問題である。すなわち、脱脂・水洗工程が追加されることにより工程が増加する。また、脱脂が不十分で脂肪酸が表面に残留したりすると、銀被覆が不均一となってしまう。さらに、脱脂することによりフレーク銅粉の無垢な表面が大気と接触することとなり、表面酸化を引き起こしてしまう。酸化した表面は銀被覆処理において銀被覆が不均一に形成する原因となり、銀被覆反応の再現性の低下、銀被覆フレーク状銅粉の酸化による経時劣化、信頼性の低下に繋がる。銀被覆が不均一に形成した銀被覆フレーク状銅粉の場合、析出した銀表面の凹凸による乱反射により、銀被覆フレーク状銅粉の色が黒くなったり、素地の銅の色が現れて赤色を帯びたりする。 In Patent Document 4, a flaky copper powder is manufactured by using atomized powder as a raw material, and mixing and flattening stearic acid as an auxiliary agent. The obtained flaky copper powder is degreased and washed with water, and then coated with silver. It describes that silver-coated flaky copper powder is prepared by reacting. In this case, although the effect of silver coating is recognized, degreasing and washing treatment during the production process is a problem. That is, a process increases by adding a degreasing and water washing process. In addition, if the degreasing is insufficient and the fatty acid remains on the surface, the silver coating becomes non-uniform. Furthermore, degreasing causes the innocuous surface of the flake copper powder to come into contact with the atmosphere, causing surface oxidation. The oxidized surface causes the silver coating to be formed unevenly in the silver coating treatment, leading to a decrease in reproducibility of the silver coating reaction, deterioration with time due to oxidation of the silver-coated flaky copper powder, and a decrease in reliability. In the case of silver-coated flaky copper powder with non-uniform silver coating, the color of the silver-coated flaky copper powder becomes black or the copper color of the base appears red due to irregular reflection due to irregularities on the deposited silver surface. I am tinged.
特許文献５には、球状の銅粉を偏平化処理し、銀被覆したのち、粒子同士を機械的に接触させて平滑化を図ることが記載されている。この場合、銀および銅に展性・延性があるとはいえ、機械的接触により銀被覆層が破れてしまうことがあり、不均一な銀被覆となりやすい。不均一な銀被覆の形成は、酸化による経時劣化、信頼性の低下を招く恐れがある。また、同文献には偏平化の際に疎水性の脂肪酸等ではなく、水溶性の界面活性剤を助剤として使用することが開示されている。しかしこの場合も界面活性剤を十分に洗浄する必要があるため、特許文献４の場合と同様、フレーク銅粉の無垢な表面が大気と接触することなり、表面酸化を引き起こしてしまう。仮に界面活性剤を洗浄せずにフレーク状銅粉を銀被覆反応に供した場合は、多量の泡が発生してしまい、反応液が溢れたり攪拌が十分に行えなかったりする不都合を招く。 Patent Document 5 describes that after a spherical copper powder is flattened and coated with silver, the particles are mechanically brought into contact with each other for smoothing. In this case, although silver and copper have malleability and ductility, the silver coating layer may be broken by mechanical contact, and a non-uniform silver coating tends to occur. The formation of a non-uniform silver coating may lead to deterioration with time and reliability due to oxidation. Further, this document discloses that a water-soluble surfactant is used as an auxiliary agent instead of a hydrophobic fatty acid or the like at the time of flattening. However, in this case as well, since the surfactant needs to be sufficiently washed, as in the case of Patent Document 4, the pure surface of the flake copper powder comes into contact with the atmosphere, causing surface oxidation. If the flaky copper powder is subjected to a silver coating reaction without washing the surfactant, a large amount of bubbles is generated, which causes inconvenience that the reaction solution overflows and stirring cannot be performed sufficiently.
特許文献６には、銀被覆フレーク状銅粉の粒度分布や銀被覆反応液について記載されているが、銀被覆層の均一性、偏平化時の助剤の種類や除去方法等については特に言及されておらず、特許文献４あるいは５と同様の方法で製造されていることから、均一な銀被覆層が形成されるとは推測しがたい。 Patent Document 6 describes the particle size distribution of silver-coated flaky copper powder and the silver-coated reaction solution, but particularly mentions the uniformity of the silver-coated layer, the type of auxiliary agent at the time of flattening, the removal method, and the like. However, since it is manufactured by the same method as in Patent Document 4 or 5, it is difficult to estimate that a uniform silver coating layer is formed.
本発明は上記の現状に鑑み、原料銅粉に銀被覆処理を施す際、[1] 原料銅粉の粒子表面に付着している疎水性物質や界面活性剤を除去するための脱脂や洗浄などの工程（以下「除去工程」という）を省略すること、[2] 薄く均一な銀被覆を安定して形成すること、を一挙に実現する銀被覆処理技術を開発し、導電ペースト用フィラーに適した高品質の銀被覆銅粉およびそれを用いた導電ペーストを安価に提供しようというものである。 In view of the above-mentioned present situation, the present invention provides [1] degreasing and washing for removing hydrophobic substances and surfactants adhering to the surface of the raw material copper powder when silver coating is applied to the raw material copper powder. Developed silver coating processing technology that realizes all of the above processes (hereinafter referred to as “removal process”) and [2] stably forms a thin and uniform silver coating, suitable for fillers for conductive pastes. High-quality silver-coated copper powder and a conductive paste using the same are provided at low cost.
発明者らは種々検討の結果、銀イオンと金属銅との置換反応を、銀イオンが存在する有機溶媒含有溶液中好ましくは有機溶媒相と水溶媒相からなるエマルジョン中で起こさせることにより、上記目的に叶う銀被覆銅粉の製造が可能になることを見出した。銀イオン源としては硝酸銀が好適に使用でき、有機溶媒としては硝酸銀等の銀塩に対して溶解度を有するアルコール、ケトン、アルデヒドおよびエーテルの１以上を使用することができる。液中にはキレート化剤やｐＨ緩衝剤を含有させることが好ましい。また、原料銅粉としては湿式還元法またはアトマイズ法により製造された銅粉に由来するものの他、機械的に偏平化されたフレーク状銅粉が好適に使用できる。 As a result of various studies, the inventors have conducted the substitution reaction between silver ions and copper metal in an organic solvent-containing solution in which silver ions are present, preferably in an emulsion composed of an organic solvent phase and an aqueous solvent phase. It has been found that it is possible to produce silver-coated copper powder that meets the purpose. As the silver ion source, silver nitrate can be suitably used, and as the organic solvent, one or more of alcohols, ketones, aldehydes and ethers having solubility in silver salts such as silver nitrate can be used. It is preferable to contain a chelating agent and a pH buffer in the liquid. Moreover, as raw material copper powder, in addition to those derived from copper powder produced by a wet reduction method or an atomization method, mechanically flattened flaky copper powder can be suitably used.
また本発明では、上記の製造方法により得ることが可能な銀被覆銅粉として、ＪＩＳ Ｚ８７２９に規定される明度Ｌ*が５０以上である銀被覆銅粉、あるいはまた、銀被覆層の平均厚さｔ（ｎｍ）と銀被覆銅粉の明度Ｌ*が下記(1)式の関係を満たす銀被覆銅粉が提供される。明度Ｌ*は銀被覆層の均一性を評価する指標となり、銀被覆層の平均厚さｔが同じである場合、Ｌ*が大きいほど均一性が高いと判断される。
３９＋０.７６ｔ−３.５×１０-3ｔ2≦Ｌ* ……(1)
ここで、銀被覆層の平均厚さｔは下記(5)式によって算出される。
ｔ＝ｘ／(１０.５×Ｓ)×１０ ……(5)
ただし、ｘは銀被覆銅粉中における銀の含有量（質量％）、１０.５は金属銀の密度（ｇ／ｃｍ3）、Ｓは金属被覆銅粉の比表面積（ｍ2／ｇ）である。
また、このような銀被覆銅粉をフィラーとして使用した導電ペーストが提供される。
In the present invention, as the silver-coated copper powder that can be obtained by the above production method, the silver-coated copper powder having a lightness L * defined by JIS Z8729 of 50 or more, or alternatively, the average thickness of the silver-coated layer There is provided a silver-coated copper powder in which t (nm) and the lightness L * of the silver-coated copper powder satisfy the relationship of the following formula (1). The lightness L * is an index for evaluating the uniformity of the silver coating layer. When the average thickness t of the silver coating layer is the same, it is judged that the uniformity is higher as L * is larger.
39 + 0.76t-3.5 × 10 −3 t 2 ≦ L * (1)
Here, the average thickness t of the silver coating layer is calculated by the following equation (5).
t = x / (10.5 × S) × 10 (5)
Where x is the silver content (% by mass) in the silver-coated copper powder, 10.5 is the density of metal silver (g / cm 3 ), and S is the specific surface area (m 2 / g) of the metal-coated copper powder. is there.
Moreover, the electrically conductive paste which uses such a silver covering copper powder as a filler is provided.
本発明によれば、原料の銅粉に脱脂・洗浄等の前処理を施すことなく、そのまま銀イオンと金属銅との置換反応を利用した銀被覆処理に供することが可能になった。その省工程化により銀被覆銅粉の製造コストが低減される。また、銀被覆処理において有機溶媒を用いるため、機械的偏平化によってフレーク状銅粉を製造する際に使用する助剤についても選択の自由度が拡がり、原料銅粉の段階において粒子形状等の適正化が容易になる。さらに、脱脂・洗浄後の表面酸化に起因する銀被覆層の不均一形成の問題が解消され、従来より薄くかつ均一な銀被覆層を安定して形成することができる。したがって本発明は、品質およびコストの両面から銀被覆銅粉およびそれを用いた導電ペーストの普及に寄与するものである。 According to the present invention, the raw copper powder can be directly subjected to a silver coating treatment using a substitution reaction between silver ions and metallic copper without performing pretreatment such as degreasing and washing. The manufacturing cost of the silver-coated copper powder is reduced by the process saving. In addition, since an organic solvent is used in the silver coating treatment, the degree of freedom in selecting the auxiliary agent used when producing the flaky copper powder by mechanical flattening is expanded, and the particle shape and the like are appropriate at the raw material copper powder stage. It becomes easy. Furthermore, the problem of non-uniform formation of the silver coating layer due to surface oxidation after degreasing and washing is solved, and a thinner and more uniform silver coating layer can be stably formed. Therefore, the present invention contributes to the widespread use of silver-coated copper powder and conductive paste using the same in terms of both quality and cost.
従来から銀イオンと金属銅との置換反応を利用して銅粒子表面に銀を被覆する方法は知られているが、本発明ではその置換反応を有機溶媒存在下で行う。すなわち、有機溶媒含有溶液中、あるいは有機溶媒相と水溶媒相からなるエマルジョン中で、銀イオンと金属銅との置換反応を起こさせる。有機溶媒を使用すると、原料銅粉の表面に疎水性の物質が付着している場合でも、反応液中での銅粉の分散性を確保することが可能になる。また、界面活性剤が付着している場合でも、反応液中での発泡を抑えることができる。このため、これらの付着物質を除去する工程を経ずに、直接置換反応を進行させることが可能になるのである。特に、フレーク状銅粉を機械的偏平化工程により製造する際には、一般的に助剤を添加することが行われ、その助剤には疎水性のものが使用されることが多い。また助剤に界面活性剤を含ませる場合もある。本発明はフレーク状銅粉を原料とする場合に極めて有効である。 Conventionally, a method of coating the surface of copper particles with silver using a substitution reaction between silver ions and metallic copper is known. In the present invention, the substitution reaction is performed in the presence of an organic solvent. That is, a substitution reaction between silver ions and metallic copper is caused in an organic solvent-containing solution or in an emulsion composed of an organic solvent phase and an aqueous solvent phase. When an organic solvent is used, it is possible to ensure the dispersibility of the copper powder in the reaction solution even when a hydrophobic substance is attached to the surface of the raw material copper powder. Moreover, even when the surfactant is adhered, foaming in the reaction solution can be suppressed. For this reason, it becomes possible to advance a substitution reaction directly, without passing through the process of removing these adhering substances. In particular, when a flaky copper powder is produced by a mechanical flattening step, an auxiliary agent is generally added, and a hydrophobic one is often used as the auxiliary agent. In addition, a surfactant may be included in the auxiliary agent. The present invention is extremely effective when flaky copper powder is used as a raw material.
ただし、単に有機溶媒を使用すれば良いわけではない。前記置換反応を進行させるためには銀イオンが溶けている必要があり、硝酸銀等の一般的に入手しやすい銀塩に対して十分な溶解度を確保しなければならない。以下、本発明に従う銀被覆の方法について具体的に説明する。 However, it is not necessary to simply use an organic solvent. In order for the substitution reaction to proceed, silver ions must be dissolved, and sufficient solubility must be ensured for silver salts such as silver nitrate that are generally available. The silver coating method according to the present invention will be specifically described below.
原料の銅粉としては、湿式還元法またはアトマイズ法によって製造された球状銅粉や、機械的に偏平化加工されたフレーク状銅粉など、種々のものが使用できる。
本発明に従う銀被覆処理では、後述のように銀の被覆量が少ないこともあり、被覆処理の前後で粒子形状や粒度分布はほとんど変化しないと見て良い。このため、製品となる銀被覆銅粉に要求される粒子形状および粒度分布をもつ原料銅粉を用意すればよい。
As the raw material copper powder, various materials such as a spherical copper powder produced by a wet reduction method or an atomizing method, and a mechanically flattened flaky copper powder can be used.
In the silver coating treatment according to the present invention, the silver coating amount may be small as described later, and it can be seen that the particle shape and particle size distribution hardly change before and after the coating treatment. For this reason, what is necessary is just to prepare the raw material copper powder which has the particle shape and particle size distribution which are requested | required of the silver covering copper powder used as a product.
発明者らの検討の結果、導電ペースト用の銀被覆フレーク状銅粉の場合、粒子の平均厚さｄが０.２μｍ以上、Ｄ５０が１〜３０μｍであり、下記(2)式で定義されるＡ値が０.１以下、あるいは更に下記(3)式で定義されるＢ値が０.５以下である銀被覆フレーク状銅粉が適していることがわかった。
Ａ値＝Ｓｄ／(Ｄ９０／Ｄ５０) ……(2)
Ｂ値＝Ｓｄ／ｄ ……(3)
ただし、平均厚さｄは走査型電子顕微鏡観察像（ＳＥＭ像）により測定されるランダムに選んだ１００個以上の粒子の平均厚さが採用でき、Ｓｄは前記平均厚さｄの標準偏差である。Ｄ５０はレーザー回折法で測定される粒度分布における５０％径（平均径）である。Ｄ９０は同粒度分布における９０％径、Ｄ１０は同粒度分布における１０％径である。
As a result of the study by the inventors, in the case of silver-coated flaky copper powder for conductive paste, the average thickness d of the particles is 0.2 μm or more, D50 is 1 to 30 μm, and is defined by the following formula (2) It was found that silver-coated flaky copper powder having an A value of 0.1 or less or a B value defined by the following formula (3) of 0.5 or less is suitable.
A value = Sd / (D90 / D50) (2)
B value = Sd / d (3)
However, the average thickness d can be an average thickness of 100 or more randomly selected particles measured by a scanning electron microscope observation image (SEM image), and Sd is a standard deviation of the average thickness d. . D50 is a 50% diameter (average diameter) in the particle size distribution measured by a laser diffraction method. D90 is a 90% diameter in the same particle size distribution, and D10 is a 10% diameter in the same particle size distribution.
粒子の平均厚さｄは０.２μｍ以上であることが望ましいが、０.３〜１.５μｍが一層好ましい。Ｄ５０は１〜３０μｍであることが望ましいが、２〜２２μｍが一層好ましい。 The average thickness d of the particles is preferably 0.2 μm or more, more preferably 0.3 to 1.5 μm. D50 is preferably 1 to 30 μm, but more preferably 2 to 22 μm.
Ａ値は粒度分布と厚みの均一性を表す尺度となる。Ａ値が０.１を超えると、その均一性が損なわれ、ペーストにしたときに粘度・焼け・焼成後の平面性などのバラツキが大きくなるので好ましくない。Ｂ値は厚みのバラツキを表す尺度となり、Ｂ値は０.５以下であることが望ましい。また(2)式、(3)式中のＳｄの値は０.５未満であるのが良い。Ｂ値が０.５を超える場合や、Ｓｄが０.５以上の場合は、ペーストにしたときに粒子同士の接触面積が少なくなり、焼結後の電気伝導性および表面平滑性の劣化につながるので好ましくない。なお、Ｓｄは０.４以下であることがより好ましく、０.２以下が一層好ましい。 The A value is a scale representing the uniformity of particle size distribution and thickness. If the A value exceeds 0.1, the uniformity is impaired, and variations such as viscosity, baking, and flatness after baking become large when made into a paste, which is not preferable. The B value is a scale representing the variation in thickness, and the B value is preferably 0.5 or less. In addition, the value of Sd in the expressions (2) and (3) is preferably less than 0.5. When the B value exceeds 0.5, or when Sd is 0.5 or more, the contact area between particles is reduced when the paste is formed, leading to deterioration in electrical conductivity and surface smoothness after sintering. Therefore, it is not preferable. Note that Sd is more preferably 0.4 or less, and even more preferably 0.2 or less.
また、導電ペースト用の銀被覆フレーク状銅粉の場合、Ｄ５０／ｄで表されるアスペクト比が５〜７０であることが好ましい。アスペクト比が５未満では、ペーストとして加工・塗布した際、外観形状の保持性および表面平滑性において球状粉の場合に比べた優位性があまり発揮されない。他方、アスペクト比が７０を超えるとペーストに加工した際の増粘による粘度調整が困難になり、ペースト塗布時の外観形状の保持性および表面平滑性が劣化するようになる。このため、アスペクト比は５〜７０の範囲とすることが好ましい。５〜６５が一層好ましい。 In the case of silver-coated flaky copper powder for conductive paste, the aspect ratio represented by D50 / d is preferably 5 to 70. When the aspect ratio is less than 5, when processed and applied as a paste, the superiority of appearance shape retention and surface smoothness compared to the case of spherical powder is not exhibited so much. On the other hand, when the aspect ratio exceeds 70, it becomes difficult to adjust the viscosity by increasing the viscosity when processed into a paste, and the retention of the external shape and the surface smoothness at the time of applying the paste deteriorate. For this reason, the aspect ratio is preferably in the range of 5 to 70. 5 to 65 is more preferable.
さらに、フレーク状粒子において、下記(4)式で表される関係が成立することが望ましい。
Ｙ＝ａＸ＋ｂ ……(4)
ここで、Ｙは前記(3)式におけるＢ値、ＸはＤ９０／Ｄ１０の値、ａは定数で０.０５〜０.２の値、ｂは定数で０.０１〜０.２の値である。
Furthermore, it is desirable that the relationship represented by the following formula (4) is satisfied in the flaky particles.
Y = aX + b (4)
Here, Y is the B value in the above equation (3), X is the value of D90 / D10, a is a constant value of 0.05 to 0.2, and b is a constant value of 0.01 to 0.2. is there.
Ｂ値とＤ９０／Ｄ１０の間には一定の相関があり、(4)式のａが０.０５〜０.２の値、ｂが０.０１〜０.２の値をとるときに良好なフレークの形状（厚み・粒径・その比）および粒度分布が得られる。この場合、Ｘの値（すなわちＤ９０／Ｄ１０の値）は２〜５の範囲にあるのが好ましい。Ｘがこの範囲にあるとき、ペーストに要求されるレオロジーおよびチキソ性を得る上で有利となる。Ｘは２〜４であることが一層好ましい。 There is a certain correlation between the B value and D90 / D10, which is good when a in Equation (4) takes a value from 0.05 to 0.2 and b takes a value from 0.01 to 0.2. The flake shape (thickness / particle size / ratio) and particle size distribution are obtained. In this case, the value of X (that is, the value of D90 / D10) is preferably in the range of 2-5. When X is in this range, it is advantageous in obtaining the rheology and thixotropy required for the paste. X is more preferably 2-4.
以上のような粒子形状および粒度分布をもつフレーク状銅粉は、例えば球状銅粉などを素材としてボールミル等で機械的に塑性変形させて偏平化する方法により製造することができる。偏平化に際しては、粒子同士の凝集や結合を防止しながら各粒子を独立した状態で加工するために、助剤を添加することが極めて有効である。例えばステアリン酸などの脂肪酸や、界面活性剤などを、０.１〜３質量％程度添加すればよい。 The flaky copper powder having the particle shape and particle size distribution as described above can be produced by, for example, a method in which spherical copper powder or the like is used as a raw material and is mechanically plastically deformed by a ball mill or the like and flattened. At the time of flattening, it is very effective to add an auxiliary agent in order to process each particle independently while preventing aggregation and bonding of the particles. For example, a fatty acid such as stearic acid or a surfactant may be added in an amount of about 0.1 to 3% by mass.
銀被覆反応を行う反応液としては、有機溶媒を含む溶液、または有機溶媒相と水溶媒相からなるエマルジョンを用いる。水に対する溶解度が大きい有機溶媒を使用する場合は均一な混合溶液となるが、溶解度が低い有機溶媒の場合は、静止状態では水相と有機溶媒相が分離するため、液を攪拌することによりエマルジョンを形成させた状態で銀被覆反応を行う。これらの反応液を使用することにより、偏平化の際に添加した助剤を除去することなく、フレーク状銅粉をそのままの銀被覆反応に供することができる。 As a reaction solution for performing the silver coating reaction, a solution containing an organic solvent or an emulsion composed of an organic solvent phase and an aqueous solvent phase is used. When using an organic solvent with a high solubility in water, a uniform mixed solution is obtained. However, in the case of an organic solvent with a low solubility, the aqueous phase and the organic solvent phase are separated in a stationary state. The silver coating reaction is carried out in the state where is formed. By using these reaction liquids, the flaky copper powder can be subjected to the silver coating reaction as it is without removing the auxiliary added at the time of flattening.
上記有機溶媒としては、水との相溶性、銀塩（主として硝酸銀）の溶解度を有する、アルコール、ケトン、アルデヒド、エーテルを使用することができる。具体的には、メタノール、エタノール、１−プロパノール、イソプロピルアルコール、１−ブタノール、２−メチルプロパノール、３−メチルプロパノール、１,１,−ジメチルエタノール、エチレングリコール、ジエチレングリコール、トリエチレングリコール、グリセリン、カルビトール、メチルカルビトール、ブチルカルビトール、セロソルブ、メチルセロソルブ、ブチルセロソルブ、テルピネオール、ホルムアルデヒド、アセトアルデヒド、アセトン、メチルエチルケトン、メチルエーテル、エチルエーテル、もしくはメチルエチルエーテル等を使用することができる。特に水を含有せず有機溶媒を単独の反応液として使用する場合は、銀塩を直接溶解することが可能な多価アルコールが好ましい。具体的には、エチレングリコール、ジエチレングリコール、グリセリン等が挙げられる。 As the organic solvent, alcohols, ketones, aldehydes, and ethers having compatibility with water and solubility of silver salts (mainly silver nitrate) can be used. Specifically, methanol, ethanol, 1-propanol, isopropyl alcohol, 1-butanol, 2-methylpropanol, 3-methylpropanol, 1,1, -dimethylethanol, ethylene glycol, diethylene glycol, triethylene glycol, glycerin, carbine Tolu, methyl carbitol, butyl carbitol, cellosolve, methyl cellosolve, butyl cellosolve, terpineol, formaldehyde, acetaldehyde, acetone, methyl ethyl ketone, methyl ether, ethyl ether, or methyl ethyl ether can be used. In particular, when an organic solvent is used as a single reaction solution without containing water, a polyhydric alcohol capable of directly dissolving a silver salt is preferable. Specific examples include ethylene glycol, diethylene glycol, glycerin and the like.
有機溶媒と水との混合溶液、またはエマルジョン中にて銀被覆を行う場合は、有機溶媒として室温（２０〜３０℃）において液体となるものを用いる必要がある。水と有機溶媒との混合比率は、使用する有機溶媒により適宜調整することができる。
また、有機溶媒と混合する水としては、不純物が混入する恐れがなければ、蒸留水、イオン交換水、工業用水等、いずれを用いても良い。
When silver coating is performed in a mixed solution of an organic solvent and water or in an emulsion, it is necessary to use an organic solvent that is liquid at room temperature (20 to 30 ° C.). The mixing ratio of water and organic solvent can be appropriately adjusted depending on the organic solvent used.
As the water mixed with the organic solvent, any water such as distilled water, ion-exchanged water, and industrial water may be used as long as there is no fear that impurities are mixed therein.
銀被覆反応に使用する銀原料としては、銀イオンを液中に存在させる必要があるため、水あるいは多くの有機溶媒に対して溶解度を有する硝酸銀を用いることが望ましい。できるだけ均一な被覆反応を実現するために、硝酸銀を固体状で添加せず、水溶液、有機溶媒、または水―有機溶媒混合液に硝酸銀を溶解した硝酸銀溶液として使用することが好ましい。目的とする銀被覆量に応じて、使用する硝酸銀溶液の濃度、有機溶媒量、および使用する硝酸銀溶液量を決める。 As a silver raw material used for the silver coating reaction, it is desirable to use silver nitrate having solubility in water or many organic solvents because silver ions need to be present in the liquid. In order to realize a coating reaction that is as uniform as possible, it is preferable to use a silver nitrate solution in which silver nitrate is dissolved in an aqueous solution, an organic solvent, or a water-organic solvent mixed solution without adding silver nitrate as a solid. The concentration of the silver nitrate solution to be used, the amount of the organic solvent, and the amount of the silver nitrate solution to be used are determined according to the target silver coating amount.
銀被覆層をより均一に形成させるために、有機溶媒を含有する反応液（混合溶液あるいはエマルジョン）中にキレート化剤を添加しても良い。キレート化剤としては、銀イオンと金属銅との置換反応により副生成する銅イオンが再析出しないよう、銅イオンとの錯安定度定数の高いものが好ましい。具体的には、エチレンジアミン四酢酸（ＥＤＴＡ）、イミノジ酢酸、ジエチレントリアミン、トリエチレンジアミン、およびそれらの塩を使用することができる。
銀被覆反応を安定かつ安全に行うにあたり、ｐＨ緩衝剤を添加しても良い。具体的には、炭酸アンモニウム、炭酸水素アンモニウム、アンモニア水、炭酸水素ナトリウムをｐＨ緩衝剤として使用することができる。
In order to form the silver coating layer more uniformly, a chelating agent may be added to a reaction solution (mixed solution or emulsion) containing an organic solvent. As the chelating agent, those having a high complex stability constant with copper ions are preferable so that copper ions by-produced by substitution reaction between silver ions and metallic copper do not reprecipitate. Specifically, ethylenediaminetetraacetic acid (EDTA), iminodiacetic acid, diethylenetriamine, triethylenediamine, and salts thereof can be used.
In performing the silver coating reaction stably and safely, a pH buffering agent may be added. Specifically, ammonium carbonate, ammonium hydrogen carbonate, aqueous ammonia, and sodium hydrogen carbonate can be used as a pH buffering agent.
銀被覆反応を行わせる際には、まず銀塩を添加する前の液中に銅粉原料を入れて攪拌し、銅粉が液中に十分分散している状態で銀塩を含んだ液を添加することが望ましい。反応温度は、反応液が凝固したり蒸発したりしなければ特に規定されるものではないが、概ね２０〜８０℃で設定可能である。反応時間は、銀の被覆量・反応温度によって異なるが、概ね１分〜５時間の範囲で設定可能である。 When conducting the silver coating reaction, first put the copper powder raw material in the liquid before adding the silver salt and stir, and then add the liquid containing the silver salt in a state where the copper powder is sufficiently dispersed in the liquid. It is desirable to add. The reaction temperature is not particularly specified as long as the reaction solution does not solidify or evaporate, but can be set at about 20 to 80 ° C. The reaction time varies depending on the silver coating amount and reaction temperature, but can be set within a range of about 1 minute to 5 hours.
このようにして得られる銀被覆銅粉は、「除去工程」を得て製造されるものと比べ銀被覆層の均一性に優れるものであるが、発明者らは銀被覆層の均一性を評価する指標として、ＪＩＳ Ｚ８７２９に規定される明度Ｌ*が使用できることを見出した。明度Ｌ*は例えば色差測定装置によって計測することができる。具体的には、粉体を測定装置の試料容器に厚さ１０ｍｍとなるように入れ、１０回タッピングして平滑化し、その粉体表面についてＬ*を測定すればよい。Ｌ*の値が大きいほど銀被覆層の均一性が高いと判断される。 The silver-coated copper powder obtained in this way is superior in the uniformity of the silver coating layer compared to that produced by obtaining the “removal step”, but the inventors evaluated the uniformity of the silver coating layer. It has been found that the lightness L * defined in JIS Z8729 can be used as an index to perform. The lightness L * can be measured by, for example, a color difference measuring device. Specifically, the powder may be put in a sample container of a measuring apparatus so as to have a thickness of 10 mm, smoothed by tapping 10 times, and L * is measured on the powder surface. It is judged that the uniformity of the silver coating layer is higher as the value of L * is larger.
本発明の方法に従えば、Ｌ*が５０以上の銀被覆フレーク状銅粉が得られる。これは、導電ペースト用フィラーとして優れた導電性および信頼性を有するものである。Ｌ*が５５以上のものが一層好ましい対象となる。 According to the method of the present invention, a silver-coated flaky copper powder having L * of 50 or more is obtained. This has excellent conductivity and reliability as a filler for conductive paste. Those having L * of 55 or more are more preferred.
また、Ｌ*は銀被覆層の厚さが厚くなるほど高い値を示す傾向を有する。このため、銀被覆層の均一性をより精度良く評価するには、銀被覆層厚さに応じて適正なＬ*値の範囲を規定することが望ましい。発明者らの検討の結果、下記(1)式を満たす銀被覆フレーク状銅粉は、種々の銀被覆量において、導電ペースト用フィラーとしての優れた導電性および信頼性を安定して呈することがわかった。特に下記(1)'式を満たすものが一層好ましい。
３９＋０.７６ｔ−３.５×１０-3ｔ2≦Ｌ* ……(1)
４３＋０.７６ｔ−３.５×１０-3ｔ2≦Ｌ* ……(1)'
ここで、ｔは銀被覆層の平均厚さ（ｎｍ）であり、前述の(5)式によって定めることができる。
Moreover, L * has a tendency to show a higher value as the thickness of the silver coating layer increases. For this reason, in order to more accurately evaluate the uniformity of the silver coating layer, it is desirable to define an appropriate L * value range according to the thickness of the silver coating layer. As a result of the study by the inventors, the silver-coated flaky copper powder satisfying the following formula (1) can stably exhibit excellent conductivity and reliability as a filler for conductive paste at various silver coating amounts. all right. In particular, those satisfying the following formula (1) ′ are more preferable.
39 + 0.76t-3.5 × 10 −3 t 2 ≦ L * (1)
43 + 0.76t-3.5 × 10 −3 t 2 ≦ L * (1) ′
Here, t is an average thickness (nm) of the silver coating layer, and can be determined by the above-described equation (5).
本発明に従えば銀被覆層の均一性が顕著に改善されるため、銀の被覆量を低減しても導電ペースト用フィラーとしての特性を確保することが可能である。例えば上記のＬ*の規定を満たすフレーク状導電ペーストにおいて、銀の被覆量を３０質量％以下としたものが好適な対象となる。２５質量％以下としたものが更に好適である。このように銀の使用量を低減した銀被覆銅粉は、銀粉と比較して大きなコストメリットを生じる。 According to the present invention, since the uniformity of the silver coating layer is remarkably improved, it is possible to ensure the characteristics as a conductive paste filler even if the amount of silver coating is reduced. For example, in the flaky conductive paste satisfying the above-mentioned definition of L * , those having a silver coating amount of 30% by mass or less are suitable. What was 25 mass% or less is still more suitable. Thus, the silver covering copper powder which reduced the usage-amount of silver produces a big cost merit compared with silver powder.
このように規定される粒子形状および粒度分布をもつ銀被覆フレーク状銅粉において、ＢＥＴ法で測定した比表面積が０.２〜２.５ｍ2／ｇ、タップ密度が１.５〜５ｇ／ｃｍ3であるのが望ましい。特に、焼成型導電性ペーストのフィラーとして使用する場合は、ＢＥＴ比表面積が０.２〜１.２ｍ2／ｇ、タップ密度が３〜５ｇ／ｃｍ3が良い。フィラーコンテンツを少なくして導電性を確保するタイプの樹脂硬化型導電性ペーストのフィラーとして使用する場合は、ＢＥＴ比表面積が０.２〜２.５ｍ2／ｇ、タップ密度が１.５〜５ｇ／ｃｍ3であるのが望ましい。 In the silver-coated flaky copper powder having the particle shape and particle size distribution as defined above, the specific surface area measured by the BET method is 0.2 to 2.5 m 2 / g, and the tap density is 1.5 to 5 g / cm. 3 is desirable. In particular, when used as a filler for a baked conductive paste, a BET specific surface area of 0.2 to 1.2 m 2 / g and a tap density of 3 to 5 g / cm 3 are preferable. When used as a filler for a resin-cured conductive paste of a type that reduces the filler content and ensures conductivity, the BET specific surface area is 0.2 to 2.5 m 2 / g and the tap density is 1.5 to 5 g. / Cm 3 is desirable.
銀被覆銅粉において、酸素含有量が１質量％を超えると、電極、電子配線、ビアホール中に銅酸化物が残留することによる耐候性の劣化や信頼性の低下が懸念される。炭素含有量が２質量％を超えると、ペーストとして使用時の焼け特性の劣化（焼きムラ・難焼成）や信頼性の低下を招く恐れがある。したがって、酸素含有量が１質量％以下、炭素含有量が２質量％以下の銀被覆銅粉が好適な対象となる。 In the silver-coated copper powder, when the oxygen content exceeds 1% by mass, there is a concern about deterioration in weather resistance and reliability due to copper oxide remaining in the electrode, electronic wiring, and via hole. When the carbon content exceeds 2% by mass, there is a risk of deterioration of burnt characteristics (burn unevenness / difficult baking) during use as paste and a decrease in reliability. Therefore, a silver-coated copper powder having an oxygen content of 1% by mass or less and a carbon content of 2% by mass or less is a suitable target.
本発明に従う銀被覆フレーク状銅粉をフィラーとして使用した導電ペーストでは、銀被覆フレーク状銅粉の粒子同士の接触面積が大きく、かつ、互いに重なり合った状態で塗布されるため、導電性の点、表面の平滑さの点、形状保持の点で従来のものにない良好な導電回路や外部電極を形成することができる。ペーストを製作する際に、本発明に従う銀被覆フレーク状銅粉だけを樹脂に分散させても良いが、粒径が０.５〜１０μｍの球状の銀被覆銅粉および／または銀粉と適切な割合で混合して樹脂に分散させても良い。０.５μｍ未満の球状粉を混合した場合は、粒子同士の凝集が激しくなって均一な分散が得られず、ペーストとして適度な特性を保てない。逆に１０μｍを超える球状粉を混合すると、通常の電子部品、配線導体やビアホールに要求される精密な電極や焼成パターンを形成することが困難となり、また焼結性が悪化するので好ましくない。なお、本発明に従う銀被覆フレーク状銅粉は、前記の球状粉と複合してまたは単独に他の形状の銀被覆銅粉を適量混合して樹脂に分散させることもできる。 In the conductive paste using the silver-coated flaky copper powder according to the present invention as a filler, the contact area between the particles of the silver-coated flaky copper powder is large, and is applied in a state of overlapping each other. It is possible to form a good conductive circuit and external electrodes that are not present in terms of surface smoothness and shape retention. When producing the paste, only the silver-coated flaky copper powder according to the present invention may be dispersed in the resin, but the spherical silver-coated copper powder and / or silver powder having a particle size of 0.5 to 10 μm and an appropriate ratio May be mixed and dispersed in the resin. When spherical powders of less than 0.5 μm are mixed, the particles are agglomerated so that uniform dispersion cannot be obtained, and appropriate characteristics as a paste cannot be maintained. Conversely, when spherical powders exceeding 10 μm are mixed, it is difficult to form precise electrodes and firing patterns required for normal electronic parts, wiring conductors and via holes, and the sinterability deteriorates, which is not preferable. The silver-coated flaky copper powder according to the present invention can be dispersed in the resin in combination with the above spherical powder or by mixing an appropriate amount of silver-coated copper powder of another shape alone.
〔実施例１〕
原料銅粉としてフレーク状銅粉を用い、銀含有量が４質量％となるように銀被覆処理を行った。銀被覆処理に用いたフレーク状銅粉の粒度分布を、ベックマンコールター社製の粒度分布測定装置ＬＳ２３０を用いて測定したところ、Ｄ１０＝５.５μｍ、Ｄ５０＝１１.３μｍ、Ｄ９０＝２１.４μｍ、Ｄ９０／Ｄ１０＝３.９であり、走査型電子顕微鏡（ＳＥＭ）観察により、粒子の平均厚さｄ＝０.８μｍ、厚さの標準偏差Ｓｄ＝０.３３を得た。Ａ値、Ｂ値、アスペクト比Ｄ５０／ｄを算出したところ、Ａ値＝０.０９、Ｂ値＝０.４１、Ｄ５０／ｄ＝１４.１であった。このフレーク状銅粉は、助剤として０.４質量％のステアリン酸が含まれているものである。
[Example 1]
A flaky copper powder was used as a raw material copper powder, and a silver coating treatment was performed so that the silver content was 4% by mass. When the particle size distribution of the flaky copper powder used in the silver coating treatment was measured using a particle size distribution measuring device LS230 manufactured by Beckman Coulter, D10 = 5.5 μm, D50 = 11.3 μm, D90 = 21.4 μm, D90 / D10 = 3.9. By observation with a scanning electron microscope (SEM), an average particle thickness d = 0.8 μm and a standard deviation Sd = 0.33 were obtained. When A value, B value, and aspect ratio D50 / d were calculated, A value = 0.09, B value = 0.41, and D50 / d = 14.1. This flaky copper powder contains 0.4% by mass of stearic acid as an auxiliary agent.
銀被覆処理は次のようにして行った。まず、フレーク状銅粉３７ｇを、２５℃のエチレングリコール（ＥＧ）７１３ｇ溶液中で分散させ、３０分間攪拌し、５質量％フレーク状銅粉を含むフレーク状銅粉分散液を準備した。また、硝酸銀２.３３ｇを２５℃のエチレングリコール２７.０９ｇ溶液中で３０分間の攪拌を行い溶解させ５質量％の銀を含む硝酸銀溶液を作製した。次に、前記フレーク状銅粉分散液と硝酸銀溶液を混合し、２５℃で管理した混合溶液を６０分間攪拌した。
その後、スラリーを濾別し、ＩＰＡ（イソプロピルアルコール）にて洗浄、窒素中で１２０℃乾燥して、銀被覆フレーク状銅粉を得た。
The silver coating treatment was performed as follows. First, 37 g of flaky copper powder was dispersed in a 713 g solution of ethylene glycol (EG) at 25 ° C. and stirred for 30 minutes to prepare a flaky copper powder dispersion containing 5 mass% flaky copper powder. Further, 2.33 g of silver nitrate was dissolved in a 27.09 g solution of ethylene glycol at 25 ° C. by stirring for 30 minutes to prepare a silver nitrate solution containing 5% by mass of silver. Next, the flaky copper powder dispersion and the silver nitrate solution were mixed, and the mixed solution managed at 25 ° C. was stirred for 60 minutes.
Thereafter, the slurry was filtered, washed with IPA (isopropyl alcohol), and dried at 120 ° C. in nitrogen to obtain a silver-coated flaky copper powder.
得られた銀被覆フレーク状銅粉を評価したところ、銀被覆量３.７質量％、ＢＥＴ比表面積０.４７ｍ2／ｇ、タップ密度３.６ｇ／ｃｍ3、酸素量０.３質量％、炭素量０.４質量％、銀被覆層の平均厚さｔ＝５ｎｍ、Ｌ*＝５０であり、均一性の高い銀被覆層を有するフレーク状銅粉であることが確認された。
なお、比表面積はＢＥＴ一点法、色差測定は東京電色製ＴＣＤ−１５００ＤＸ、銀被覆量は銀被覆フレーク状銅粉を酸に溶解させてＩＣＰにて評価した。
When the obtained silver-coated flaky copper powder was evaluated, the silver coating amount was 3.7% by mass, the BET specific surface area was 0.47 m 2 / g, the tap density was 3.6 g / cm 3 , the oxygen amount was 0.3% by mass, The carbon content was 0.4% by mass, the average thickness t of the silver coating layer was t = 5 nm, and L * = 50, and it was confirmed that the flake copper powder had a highly uniform silver coating layer.
The specific surface area was evaluated by the BET single point method, the color difference measurement was TCD-1500DX manufactured by Tokyo Denshoku, and the silver coating amount was evaluated by ICP after dissolving silver-coated flaky copper powder in acid.
〔実施例２〕
フレーク状銅粉を用い、銀含有量が２０質量％となるように銀被覆処理を行った。銀被覆処理に用いたフレーク状銅粉について実施例１と同様の方法で測定したところ、Ｄ１０＝３.３μｍ、Ｄ５０＝６.３μｍ、Ｄ９０＝１２.９μｍ、Ｄ９０／Ｄ１０＝３.９、ｄ＝０.４μｍ、Ｓｄ＝０.１４、Ａ値＝０.０４、Ｂ値＝０.３５、Ｄ５０／ｄ＝１５.８であった。このフレーク状銅粉は、助剤として０.７質量％のステアリン酸が含まれているものである。
[Example 2]
Using flaky copper powder, silver coating treatment was performed so that the silver content was 20% by mass. The flaky copper powder used in the silver coating treatment was measured by the same method as in Example 1. As a result, D10 = 3.3 μm, D50 = 6.3 μm, D90 = 12.9 μm, D90 / D10 = 3.9, d = 0.4 μm, Sd = 0.14, A value = 0.04, B value = 0.35, D50 / d = 15.8. This flaky copper powder contains 0.7% by mass of stearic acid as an auxiliary agent.
銀被覆処理は次のようにして行った。炭酸アンモニウム４７.２ｇとエチレンジアミン四酢酸二ナトリウム塩二水和物（ＥＤＴＡ・２Ｎa）９４.５ｇを純水３７６ｇに溶解した溶液と、純水４８.７ｇに硝酸銀１５.７ｇを溶解した硝酸銀水溶液を混合して、硝酸銀水溶液を調製した。また、炭酸アンモニウム１９ｇとＥＤＴＡ・２Ｎa塩１９ｇを純水１１１ｇに溶解させた後、イソプロピルアルコール（ＩＰＡ）１９８ｇを添加し、フレーク状銅粉４０ｇを加え攪拌してフレーク状銅粉分散液を準備した。このフレーク状銅粉分散液の液温を５０℃に調整し、前記の硝酸銀水溶液を添加し、６０分間攪拌しながら保持した。
攪拌中は、イソプロピルアルコールが主成分の有機溶媒相と、純水が主成分の水相からなるエマルジョン状態となっていた。反応終了後、室温まで冷却して攪拌を止めると、エマルジョンを形成していた反応スラリーは、比重の差により相分離した。
反応スラリーを濾別し、純水およびＩＰＡにて洗浄、窒素中で１２０℃乾燥して、銀被覆フレーク状銅粉を得た。
The silver coating treatment was performed as follows. A solution prepared by dissolving 47.2 g of ammonium carbonate and 94.5 g of ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA · 2Na) in 376 g of pure water, and an aqueous solution of silver nitrate obtained by dissolving 15.7 g of silver nitrate in 48.7 g of pure water A silver nitrate aqueous solution was prepared by mixing. Further, 19 g of ammonium carbonate and 19 g of EDTA · 2Na salt were dissolved in 111 g of pure water, 198 g of isopropyl alcohol (IPA) was added, and 40 g of flaky copper powder was added and stirred to prepare a flaky copper powder dispersion. . The liquid temperature of this flaky copper powder dispersion was adjusted to 50 ° C., the aqueous silver nitrate solution was added, and the mixture was held with stirring for 60 minutes.
During stirring, the emulsion was in an emulsion state composed of an organic solvent phase mainly composed of isopropyl alcohol and an aqueous phase mainly composed of pure water. When the stirring was stopped after cooling to room temperature after completion of the reaction, the reaction slurry forming the emulsion was phase-separated due to the difference in specific gravity.
The reaction slurry was filtered, washed with pure water and IPA, and dried at 120 ° C. in nitrogen to obtain a silver-coated flaky copper powder.
得られた銀被覆フレーク状銅粉を実施例１と同様の方法で評価したところ、銀被覆量２１質量％、ＢＥＴ比表面積１.２ｍ2／ｇ、タップ密度２.２ｇ／ｃｍ3、酸素量０.６質量％、炭素量０.３質量％、銀被覆層の平均厚さｔ＝１６ｎｍ、Ｌ*＝５６であり、均一性の高い銀被覆層を有するフレーク状銅粉であることが確認された。 The obtained silver-coated flaky copper powder was evaluated in the same manner as in Example 1. As a result, the silver coating amount was 21% by mass, the BET specific surface area was 1.2 m 2 / g, the tap density was 2.2 g / cm 3 , and the oxygen amount. 0.6% by mass, 0.3% by mass of carbon, average thickness of silver coating layer t = 16 nm, L * = 56, confirmed to be a flaky copper powder having a highly uniform silver coating layer It was done.
〔実施例３〕
フレーク状銅粉を用い、銀含有量が１０質量％となるように銀被覆処理を行った。銀被覆処理に用いたフレーク状銅粉について実施例１と同様の方法で測定したところ、Ｄ１０＝２.６μｍ、Ｄ５０＝４.１μｍ、Ｄ９０＝７.３μｍ、Ｄ９０／Ｄ１０＝２.９、ｄ＝０.８μｍ、Ｓｄ＝０.２７、Ａ値＝０.０９、Ｂ値＝０.３３、Ｄ５０／ｄ＝５.１であった。このフレーク状銅粉は、助剤として０.７質量％のステアリン酸が含まれているものである。
Example 3
Using flaky copper powder, silver coating treatment was performed so that the silver content was 10% by mass. The flaky copper powder used in the silver coating treatment was measured in the same manner as in Example 1. As a result, D10 = 2.6 μm, D50 = 4.1 μm, D90 = 7.3 μm, D90 / D10 = 2.9, d = 0.8 µm, Sd = 0.27, A value = 0.09, B value = 0.33, D50 / d = 5.1. This flaky copper powder contains 0.7% by mass of stearic acid as an auxiliary agent.
銀被覆処理は次のようにして行った。炭酸アンモニウム３１.５ｇとエチレンジアミン四酢酸二ナトリウム塩二水和物（ＥＤＴＡ・２Ｎa）６３ｇを純水２５０ｇに溶解した溶液と、純水３２.４ｇに硝酸銀１０.５ｇを溶解した硝酸銀水溶液を混合して、硝酸銀水溶液を調製した。また、炭酸アンモニウム２８.６ｇとＥＤＴＡ・２Ｎa塩２８.６ｇを純水１６６ｇに溶解させた後、ｔ−ブチルアルコール１６６ｇを添加し、フレーク状銅粉６０ｇを加え攪拌してフレーク状銅粉分散液を準備した。このフレーク状銅粉分散液の液温を５０℃に調整し、前記の硝酸銀水溶液を添加し、６０分間攪拌しながら保持した。
攪拌中は、ｔ−ブチルアルコールが主成分の有機溶媒相と、純水が主成分の水相からなるエマルジョン状態となっていた。反応終了後、室温まで冷却して攪拌を止めると、エマルジョンを形成していた反応スラリーは、比重の差により相分離した。
反応スラリーを濾別し、純水およびＩＰＡにて洗浄、窒素中で１２０℃乾燥して、銀被覆フレーク状銅粉を得た。
The silver coating treatment was performed as follows. A solution in which 31.5 g of ammonium carbonate and 63 g of ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA · 2Na) are dissolved in 250 g of pure water and an aqueous solution of silver nitrate in which 10.5 g of silver nitrate is dissolved in 32.4 g of pure water are mixed. Thus, an aqueous silver nitrate solution was prepared. In addition, after dissolving 28.6 g of ammonium carbonate and 28.6 g of EDTA · 2Na salt in 166 g of pure water, 166 g of t-butyl alcohol was added, and 60 g of flaky copper powder was added and stirred to obtain a flaky copper powder dispersion. Prepared. The liquid temperature of this flaky copper powder dispersion was adjusted to 50 ° C., the aqueous silver nitrate solution was added, and the mixture was held with stirring for 60 minutes.
During the stirring, the emulsion was composed of an organic solvent phase mainly composed of t-butyl alcohol and an aqueous phase mainly composed of pure water. When the stirring was stopped after cooling to room temperature after completion of the reaction, the reaction slurry forming the emulsion was phase-separated due to the difference in specific gravity.
The reaction slurry was filtered, washed with pure water and IPA, and dried at 120 ° C. in nitrogen to obtain a silver-coated flaky copper powder.
得られた銀被覆フレーク状銅粉を実施例１と同様の方法で評価したところ、銀被覆量１０質量％、ＢＥＴ比表面積０.４９ｍ2／ｇ、タップ密度３.６ｇ／ｃｍ3、酸素量０.３質量％、炭素量０.５質量％、銀被覆層の平均厚さｔ＝２０ｎｍ、Ｌ*＝５８であり、均一性の高い銀被覆層を有するフレーク状銅粉であることが確認された。 When the obtained silver-coated flaky copper powder was evaluated in the same manner as in Example 1, the silver coating amount was 10% by mass, the BET specific surface area was 0.49 m 2 / g, the tap density was 3.6 g / cm 3 , and the oxygen content. 0.3% by mass, 0.5% by mass of carbon, average thickness of silver coating layer t = 20 nm, L * = 58, confirmed to be a flaky copper powder having a highly uniform silver coating layer It was done.
〔実施例４〕
フレーク状銅粉を用い、銀含有量が１５質量％となるように銀被覆処理を行った。銀被覆処理に用いたフレーク状銅粉は、実施例３で用いたものと同じである。
Example 4
Using flaky copper powder, silver coating treatment was performed so that the silver content was 15% by mass. The flaky copper powder used for the silver coating treatment is the same as that used in Example 3.
銀被覆処理は次のようにして行った。炭酸アンモニウム３３ｇとエチレンジアミン四酢酸二ナトリウム塩二水和物（ＥＤＴＡ・２Ｎa）６７ｇを純水２６６ｇに溶解した溶液と、純水３４.４ｇに硝酸銀１１.１ｇを溶解した硝酸銀水溶液を混合して、硝酸銀水溶液を調製した。また、炭酸アンモニウム１９ｇとＥＤＴＡ・２Ｎa塩１９ｇを純水１１１ｇに溶解させた後、イソプロピルアルコール１５２ｇを添加し、フレーク状銅粉４０ｇを加え攪拌してフレーク状銅粉分散液を準備した。このフレーク状銅粉分散液の液温を５０℃に調整し、前記の硝酸銀水溶液を添加し、６０分間攪拌しながら保持した。
攪拌中は、イソプロピルアルコールが主成分の有機溶媒相と、純水が主成分の水相からなるエマルジョン状態となっていた。反応終了後、室温まで冷却して攪拌を止めると、エマルジョンを形成していた反応スラリーは、比重の差により相分離した。
反応スラリーを濾別し、純水およびＩＰＡにて洗浄、窒素中で１２０℃乾燥して、銀被覆フレーク状銅粉を得た。
The silver coating treatment was performed as follows. A solution in which 33 g of ammonium carbonate and 67 g of ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA · 2Na) were dissolved in 266 g of pure water and an aqueous solution of silver nitrate in which 11.1 g of silver nitrate was dissolved in 34.4 g of pure water were mixed. An aqueous silver nitrate solution was prepared. Moreover, after dissolving 19 g of ammonium carbonate and 19 g of EDTA · 2Na salt in 111 g of pure water, 152 g of isopropyl alcohol was added, and 40 g of flaky copper powder was added and stirred to prepare a flaky copper powder dispersion. The liquid temperature of this flaky copper powder dispersion was adjusted to 50 ° C., the aqueous silver nitrate solution was added, and the mixture was held with stirring for 60 minutes.
During stirring, the emulsion was in an emulsion state composed of an organic solvent phase mainly composed of isopropyl alcohol and an aqueous phase mainly composed of pure water. When the stirring was stopped after cooling to room temperature after completion of the reaction, the reaction slurry forming the emulsion was phase-separated due to the difference in specific gravity.
The reaction slurry was filtered, washed with pure water and IPA, and dried at 120 ° C. in nitrogen to obtain a silver-coated flaky copper powder.
得られた銀被覆フレーク状銅粉を実施例１と同様の方法で評価したところ、銀被覆量１６質量％、ＢＥＴ比表面積０.４８ｍ2／ｇ、タップ密度４.０ｇ／ｃｍ3、酸素量０.２質量％、炭素量０.２質量％、銀被覆層の平均厚さｔ＝３２ｎｍ、Ｌ*＝６２であり、均一性の高い銀被覆層を有するフレーク状銅粉であることが確認された。 The obtained silver-coated flaky copper powder was evaluated in the same manner as in Example 1. As a result, the silver coating amount was 16% by mass, the BET specific surface area was 0.48 m 2 / g, the tap density was 4.0 g / cm 3 , and the oxygen amount. 0.2% by mass, 0.2% by mass of carbon, average thickness of silver coating layer t = 32 nm, L * = 62, and confirmed to be a flaky copper powder having a highly uniform silver coating layer It was done.
〔実施例５〕
フレーク状銅粉を用い、銀含有量が５質量％となるように銀被覆処理を行った。銀被覆処理に用いたフレーク状銅粉は、実施例１で用いたものと同じである。
Example 5
Using flaky copper powder, silver coating treatment was performed so that the silver content was 5% by mass. The flaky copper powder used for the silver coating treatment is the same as that used in Example 1.
銀被覆処理は次のようにして行った。炭酸アンモニウム２０ｇとエチレンジアミン四酢酸二ナトリウム塩二水和物（ＥＤＴＡ・２Ｎa）４０ｇを純水１６０ｇに溶解した溶液と、純水２０.５ｇに硝酸銀６.６ｇを溶解した硝酸銀水溶液を混合して、硝酸銀水溶液を調製した。また、炭酸アンモニウム３８ｇとＥＤＴＡ・２Ｎa塩３８ｇを純水２２２ｇに溶解させた後、イソプロピルアルコール２２２ｇを添加し、フレーク状銅粉８０ｇを加え攪拌してフレーク状銅粉分散液を準備した。このフレーク状銅粉分散液の液温を５０℃に調整し、前記の硝酸銀水溶液を添加し、６０分間攪拌しながら保持した。
攪拌中は、イソプロピルアルコールが主成分の有機溶媒相と、純水が主成分の水相からなるエマルジョン状態となっていた。反応終了後、室温まで冷却して攪拌を止めると、エマルジョンを形成していた反応スラリーは、比重の差により相分離した。
反応スラリーを濾別し、純水およびＩＰＡにて洗浄、窒素中で１２０℃乾燥して、銀被覆フレーク状銅粉を得た。
The silver coating treatment was performed as follows. A solution in which 20 g of ammonium carbonate and 40 g of ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA · 2Na) are dissolved in 160 g of pure water and an aqueous solution of silver nitrate in which 6.6 g of silver nitrate is dissolved in 20.5 g of pure water are mixed. An aqueous silver nitrate solution was prepared. Moreover, after dissolving 38 g of ammonium carbonate and 38 g of EDTA · 2Na salt in 222 g of pure water, 222 g of isopropyl alcohol was added, and 80 g of flaky copper powder was added and stirred to prepare a flaky copper powder dispersion. The liquid temperature of this flaky copper powder dispersion was adjusted to 50 ° C., the aqueous silver nitrate solution was added, and the mixture was held with stirring for 60 minutes.
During stirring, the emulsion was in an emulsion state composed of an organic solvent phase mainly composed of isopropyl alcohol and an aqueous phase mainly composed of pure water. When the stirring was stopped after cooling to room temperature after completion of the reaction, the reaction slurry forming the emulsion was phase-separated due to the difference in specific gravity.
The reaction slurry was filtered, washed with pure water and IPA, and dried at 120 ° C. in nitrogen to obtain a silver-coated flaky copper powder.
得られた銀被覆フレーク状銅粉を実施例１と同様の方法で評価したところ、銀被覆量５質量％、ＢＥＴ比表面積２.４ｍ2／ｇ、タップ密度２.１ｇ／ｃｍ3、酸素量０.８質量％、炭素量０.２質量％、銀被覆層の平均厚さｔ＝２ｎｍ、Ｌ*＝５０であり、均一性の高い銀被覆層を有するフレーク状銅粉であることが確認された。 The obtained silver-coated flaky copper powder was evaluated in the same manner as in Example 1. As a result, the silver coating amount was 5% by mass, the BET specific surface area was 2.4 m 2 / g, the tap density was 2.1 g / cm 3 , and the oxygen amount. 0.8% by mass, 0.2% by mass of carbon, average thickness of silver coating layer t = 2 nm, L * = 50, confirmed to be a flaky copper powder having a highly uniform silver coating layer It was done.
〔比較例１〕
フレーク状銅粉を用い、有機溶媒を使用せずに、銀含有量が１０％重量となるように銀被覆処理を行った。銀被覆処理に用いたフレーク状銅粉は、実施例２で用いたものと同じである。
[Comparative Example 1]
Using flaky copper powder, a silver coating treatment was performed so that the silver content was 10% by weight without using an organic solvent. The flaky copper powder used for the silver coating treatment is the same as that used in Example 2.
フレーク状銅粉は、そのままでは水に分散しないため、助剤のステアリン酸を洗浄除去した後、銀被覆処理を行った。助剤の洗浄除去として、純水１００ｇ、５０質量％のＮaＯＨ水溶液２０ｇおよびイソプロピルアルコール１５０ｇを混合し、これにフレーク状銅粉１２０ｇを加え、１５分間攪拌し、濾別・純水洗浄した。洗浄により、炭素量（すなわちステアリン酸に由来する炭素の量）が０.２質量％まで減少し、ある程度水に分散するようになる。また、酸素量とＬ*を測定したところ、酸素量は１.７質量％、Ｌ*＝３８であった。 Since the flaky copper powder does not disperse in water as it is, the auxiliary stearic acid was washed and removed, followed by silver coating treatment. As washing and removal of the auxiliary agent, 100 g of pure water, 20 g of 50 mass% NaOH aqueous solution and 150 g of isopropyl alcohol were mixed, 120 g of flaky copper powder was added thereto, stirred for 15 minutes, filtered and washed with pure water. By washing, the amount of carbon (that is, the amount of carbon derived from stearic acid) is reduced to 0.2% by mass and dispersed in water to some extent. Further, when the amount of oxygen and L * were measured, the amount of oxygen was 1.7% by mass and L * = 38.
濾別・純水洗浄したフレーク状銅粉のケーキは、乾燥させることなく、そのまま銀被覆処理に用い、銀被覆処理を次のようにして行った。炭酸アンモニウム４２ｇとエチレンジアミン四酢酸二ナトリウム塩二水和物（ＥＤＴＡ・２Ｎa）８４ｇを純水３３０ｇに溶解した溶液と、純水４３.３ｇに硝酸銀１４ｇを溶解した硝酸銀水溶液を混合して、硝酸銀水溶液を調製した。また、炭酸アンモニウム３８ｇとＥＤＴＡ・２Ｎa塩３８ｇを純水４４３ｇに溶解させた後、助剤を洗浄除去したフレーク状銅粉のケーキ８０ｇを加え攪拌した。液温を５０℃に調整し、準備していた硝酸銀水溶液を添加し、６０分間攪拌しながら保持した。
冷却後、スラリーを濾別し、純水およびＩＰＡにて洗浄、窒素中で１２０℃乾燥して、銀被覆フレーク状銅粉を得た。
The cake of flaky copper powder that had been filtered and washed with pure water was used for the silver coating treatment as it was without drying, and the silver coating treatment was performed as follows. A solution of 42 g of ammonium carbonate and 84 g of ethylenediaminetetraacetic acid disodium salt dihydrate (EDTA · 2Na) dissolved in 330 g of pure water and a silver nitrate aqueous solution in which 14 g of silver nitrate was dissolved in 43.3 g of pure water were mixed to obtain a silver nitrate aqueous solution. Was prepared. Further, 38 g of ammonium carbonate and 38 g of EDTA · 2Na salt were dissolved in 443 g of pure water, and then 80 g of a flaky copper powder cake from which the auxiliary agent had been washed away was added and stirred. The liquid temperature was adjusted to 50 ° C., the prepared silver nitrate aqueous solution was added, and the mixture was held with stirring for 60 minutes.
After cooling, the slurry was filtered, washed with pure water and IPA, and dried at 120 ° C. in nitrogen to obtain silver-coated flaky copper powder.
得られた銀被覆フレーク状銅粉を実施例１と同様の方法で評価したところ、銀被覆量１０質量％、ＢＥＴ比表面積１.１ｍ2／ｇ、タップ密度２.７ｇ／ｃｍ3、酸素量１.３質量％、炭素量０.２質量％、銀被覆層の平均厚さｔ＝８ｎｍ、Ｌ*＝４４であった。この銀被覆銅粉は見た目にも色が暗く、前記各実施例のものと比べ銀被覆層の均一性が低い。 The obtained silver-coated flaky copper powder was evaluated in the same manner as in Example 1. The silver coating amount was 10% by mass, the BET specific surface area was 1.1 m 2 / g, the tap density was 2.7 g / cm 3 , and the oxygen amount. The content was 1.3% by mass, the carbon content was 0.2% by mass, the average thickness t of the silver coating layer was t = 8 nm, and L * = 44. This silver-coated copper powder is dark in appearance, and the uniformity of the silver coating layer is lower than those in the above examples.
図１には、後述の実施例および比較例の銀被覆フレーク状銅粉（一部は原料銅粉）について、銀被覆層の平均厚さｔ（ｎｍ）とＬ*の関係を例示する。本発明に従えば、(1)式、あるいはさらに(1)'式を満たす銀被覆フレーク状銅粉の実現が可能になる。 FIG. 1 illustrates the relationship between the average thickness t (nm) of the silver coating layer and L * for silver-coated flaky copper powder (partially raw material copper powder) of Examples and Comparative Examples described later. According to the present invention, it is possible to realize a silver-coated flaky copper powder that satisfies the formula (1) or further the formula (1) ′.
Claims (17)
３９＋０.７６ｔ−３.５×１０-3ｔ2≦Ｌ* ……(1) Silver-coated copper powder in which the average thickness t (nm) of the silver coating layer and the brightness L * of the silver-coated copper powder satisfy the relationship of the following formula (1).
39 + 0.76t-3.5 × 10 −3 t 2 ≦ L * (1)
Ａ値＝Ｓｄ／(Ｄ９０／Ｄ５０) ……(2)
ただし、平均厚さｄは電子顕微鏡を用いて測定される１００個以上の粒子の平均厚さ、Ｓｄは前記平均厚さｄの標準偏差、Ｄ５０はレーザー回折法で測定される粒度分布における５０％径（平均径）、Ｄ９０は同粒度分布における９０％径、Ｄ１０は同粒度分布における１０％径である。 11. The composition according to claim 9, comprising flake-shaped particles, having an average thickness d of 0.2 μm or more, D50 of 1 to 30 μm, and an A value defined by the following formula (2) of 0.1 or less. Silver-coated copper powder.
A value = Sd / (D90 / D50) (2)
However, the average thickness d is an average thickness of 100 or more particles measured using an electron microscope, Sd is a standard deviation of the average thickness d, and D50 is 50% in a particle size distribution measured by a laser diffraction method. The diameter (average diameter), D90 is a 90% diameter in the same particle size distribution, and D10 is a 10% diameter in the same particle size distribution.
Ｂ値＝Ｓｄ／ｄ ……(3)
ただし、ｄは電子顕微鏡を用いて測定される１００個以上の粒子の平均厚さ、Ｓｄは前記平均厚さｄの標準偏差である。 The silver-coated copper powder according to claim 9 or 10, which is composed of flaky particles and has a B value defined by the following formula (3) of 0.5 or less.
B value = Sd / d (3)
However, d is an average thickness of 100 or more particles measured using an electron microscope, and Sd is a standard deviation of the average thickness d.
Ｙ＝ａＸ＋ｂ ……(4)
ここで、Ｙは下記(3)式におけるＢ値、ＸはＤ９０／Ｄ１０の値、ａは定数で０.０５〜０.２の値、ｂは定数で０.０１〜０.２の値である。
Ｂ値＝Ｓｄ／ｄ ……(3)
ただし、ｄは電子顕微鏡を用いて測定される１００個以上の粒子の平均厚さ、Ｓｄは前記平均厚さｄの標準偏差、Ｄ５０はレーザー回折法で測定される粒度分布における５０％径（平均径）、Ｄ９０は同粒度分布における９０％径である。 The silver-coated copper powder according to claim 9 or 10, wherein the silver-coated copper powder is composed of flaky particles and satisfies the relationship represented by the following formula (4).
Y = aX + b (4)
Here, Y is a B value in the following equation (3), X is a value of D90 / D10, a is a constant value of 0.05 to 0.2, and b is a constant value of 0.01 to 0.2. is there.
B value = Sd / d (3)
Where d is an average thickness of 100 or more particles measured using an electron microscope, Sd is a standard deviation of the average thickness d, and D50 is a 50% diameter (average) in a particle size distribution measured by a laser diffraction method. Diameter), D90 is a 90% diameter in the same particle size distribution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004352024A JP4660701B2 (en) | 2004-12-03 | 2004-12-03 | Silver-coated copper powder, method for producing the same, and conductive paste |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004352024A JP4660701B2 (en) | 2004-12-03 | 2004-12-03 | Silver-coated copper powder, method for producing the same, and conductive paste |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2010157535A Division JP5453598B2 (en) | 2010-07-12 | 2010-07-12 | Silver-coated copper powder and conductive paste |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2006161081A true JP2006161081A (en) | 2006-06-22 |
| JP4660701B2 JP4660701B2 (en) | 2011-03-30 |
Family
ID=36663431
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2004352024A Active JP4660701B2 (en) | 2004-12-03 | 2004-12-03 | Silver-coated copper powder, method for producing the same, and conductive paste |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4660701B2 (en) |
Cited By (29)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2006129487A1 (en) * | 2005-05-30 | 2006-12-07 | Sumitomo Electric Industries, Ltd. | Conductive paste and multilayer printed wiring board using same |
| WO2007007617A1 (en) * | 2005-07-08 | 2007-01-18 | Daikin Industries, Ltd. | Surface treatment in presence of organic solvent |
| WO2008059789A1 (en) * | 2006-11-17 | 2008-05-22 | Nippon Mining & Metals Co., Ltd. | Silver-plated fine copper powder, conductive paste produced from silver-plated fine copper powder, and process for producing silver-plated fine copper powder |
| CN100448570C (en) * | 2007-02-01 | 2009-01-07 | 北京化工大学 | Preparation method of nanometer copper-silver bimetallic composite powder |
| JP2010065260A (en) * | 2008-09-09 | 2010-03-25 | Tohoku Univ | Method for producing silver-coated copper fine powder |
| JP2011044509A (en) * | 2009-08-20 | 2011-03-03 | Mitsubishi Materials Corp | Conductive ink composition, and solar cell module formed using the composition |
| JP2013045742A (en) * | 2011-08-26 | 2013-03-04 | Yokohama Rubber Co Ltd:The | Conductive composition, solar cell, and solar cell module |
| JP2013185213A (en) * | 2012-03-08 | 2013-09-19 | Tokyo Institute Of Technology | Metal nanoparticle, method for producing the same, and conductive ink |
| KR101402437B1 (en) | 2013-10-15 | 2014-06-03 | 한동철 | The method of silver coated flake copper powder used membrane sheet circuit printing conductive paste |
| KR101403371B1 (en) | 2013-12-31 | 2014-06-03 | 충남대학교산학협력단 | Manufacturing method of metal particle and metal particle using thereof, and conductive paste and shielding electromagnetic wave containing the same |
| CN103890966A (en) * | 2011-10-18 | 2014-06-25 | 迪睿合电子材料有限公司 | Conductive adhesive, solar cell module using same, and method for manufacturing solar cell module |
| WO2014156978A1 (en) | 2013-03-28 | 2014-10-02 | 東洋アルミニウム株式会社 | Conductive particles, method for producing same, conductive resin composition containing same, and conductive coated material |
| JP2015021145A (en) * | 2013-07-16 | 2015-02-02 | Ｄｏｗａエレクトロニクス株式会社 | Silver-coated copper alloy powder and method for producing the same |
| KR101499141B1 (en) * | 2013-09-06 | 2015-03-11 | 동아대학교 산학협력단 | Conductive Powder, Method for Manufacturing the Same, and Conductive Paste Using the Conductive Powder |
| WO2015107996A1 (en) | 2014-01-14 | 2015-07-23 | 東洋アルミニウム株式会社 | Composite conductive particles, conductive resin composition containing same and conductive coated article |
| JP2016148073A (en) * | 2015-02-10 | 2016-08-18 | 国立大学法人大阪大学 | Joining method |
| KR20170031210A (en) | 2014-08-26 | 2017-03-20 | 스미토모 긴조쿠 고잔 가부시키가이샤 | Silver-coated copper powder, and conductive paste, conductive coating material and conductive sheet each of which uses same |
| KR20170031215A (en) | 2014-09-12 | 2017-03-20 | 스미토모 긴조쿠 고잔 가부시키가이샤 | Silver-coated copper powder, and conductive paste, conductive coating material and conductive sheet, each of which uses said silver-coated copper powder |
| US20170218512A1 (en) * | 2016-02-02 | 2017-08-03 | National Cheng Kung University | Method of Fabricating High-Conductivity Thick-film Copper Paste Coated with Nano-Silver for Being Sintered in the Air |
| JP2017150086A (en) * | 2012-01-17 | 2017-08-31 | Ｄｏｗａエレクトロニクス株式会社 | Silver coated copper alloy powder and manufacturing method therefor |
| JP2018509524A (en) * | 2015-01-09 | 2018-04-05 | クラークソン ユニバーシティ | Silver-coated copper flakes and method for producing the same |
| CN109355034A (en) * | 2018-10-24 | 2019-02-19 | 焦作市高森建电子科技有限公司 | A kind of conducting resinl silver-coated copper powder and preparation method thereof |
| US10287442B2 (en) | 2011-12-13 | 2019-05-14 | Heraeus Precious Metals North America Conshohocken Llc | Electrically conductive polymeric compositions, contacts, assemblies, and methods |
| US10486231B2 (en) | 2015-08-31 | 2019-11-26 | Mitsui Mining & Smelting Co., Ltd. | Silver-coated copper powder |
| JP2020073727A (en) * | 2016-09-29 | 2020-05-14 | Ｊｘ金属株式会社 | Surface-treated metal powder for laser sintering |
| US10654101B2 (en) | 2015-05-15 | 2020-05-19 | Sumitomo Metal Mining Co., Ltd. | Silver-coated copper powder, copper paste using same, conductive coating material, conductive sheet, and method for producing silver-coated copper powder |
| US10695830B2 (en) | 2015-05-15 | 2020-06-30 | Sumitomo Metal Mining Co., Ltd. | Copper powder, copper paste using same, conductive coating material, conductive sheet, and method for producing copper powder |
| CN112355322A (en) * | 2020-11-18 | 2021-02-12 | 深圳市夏特科技有限公司 | Preparation device and preparation method of flaky silver-coated copper powder |
| JP7018551B1 (en) * | 2020-08-26 | 2022-02-10 | 三井金属鉱業株式会社 | Silver-coated flake-shaped copper powder and its manufacturing method |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104999076B (en) * | 2015-06-01 | 2017-11-17 | 浙江亚通焊材有限公司 | The method that one kettle way prepares the controllable silver-colored copper-clad nano-powder of shell thickness |
| JP6762848B2 (en) * | 2016-11-02 | 2020-09-30 | 東洋アルミニウム株式会社 | Paste composition |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53134759A (en) * | 1977-04-28 | 1978-11-24 | Fujikura Kasei Kk | Production of copmosite metal powder |
| JPH01119602A (en) * | 1987-11-02 | 1989-05-11 | Mitsui Mining & Smelting Co Ltd | Production of silver-coated copper powder |
| JP2002245849A (en) * | 2001-02-13 | 2002-08-30 | Dowa Mining Co Ltd | Conductive filter for conductive paste and manufacturing method of the same |
| JP2004052044A (en) * | 2002-07-19 | 2004-02-19 | Mitsui Mining & Smelting Co Ltd | Silver-coated copper powder and its manufacturing method |
| JP2004068111A (en) * | 2002-08-08 | 2004-03-04 | Mitsui Mining & Smelting Co Ltd | Silver coated flake copper powder and method for manufacturing silver coated flake copper powder and conductive paste using silver coated flake copper powder |
| JP2004510885A (en) * | 2000-10-06 | 2004-04-08 | アトーテヒ ドイッチュラント ゲゼルシャフト ミット ベシュレンクテル ハフツング | Baths and methods for electroless plating of silver on metal surfaces |
-
2004
- 2004-12-03 JP JP2004352024A patent/JP4660701B2/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53134759A (en) * | 1977-04-28 | 1978-11-24 | Fujikura Kasei Kk | Production of copmosite metal powder |
| JPH01119602A (en) * | 1987-11-02 | 1989-05-11 | Mitsui Mining & Smelting Co Ltd | Production of silver-coated copper powder |
| JP2004510885A (en) * | 2000-10-06 | 2004-04-08 | アトーテヒ ドイッチュラント ゲゼルシャフト ミット ベシュレンクテル ハフツング | Baths and methods for electroless plating of silver on metal surfaces |
| JP2002245849A (en) * | 2001-02-13 | 2002-08-30 | Dowa Mining Co Ltd | Conductive filter for conductive paste and manufacturing method of the same |
| JP2004052044A (en) * | 2002-07-19 | 2004-02-19 | Mitsui Mining & Smelting Co Ltd | Silver-coated copper powder and its manufacturing method |
| JP2004068111A (en) * | 2002-08-08 | 2004-03-04 | Mitsui Mining & Smelting Co Ltd | Silver coated flake copper powder and method for manufacturing silver coated flake copper powder and conductive paste using silver coated flake copper powder |
Cited By (43)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8617688B2 (en) | 2005-05-30 | 2013-12-31 | Sumitomo Electric Industries, Ltd. | Conductive paste and multilayer printed wiring board using the same |
| WO2006129487A1 (en) * | 2005-05-30 | 2006-12-07 | Sumitomo Electric Industries, Ltd. | Conductive paste and multilayer printed wiring board using same |
| WO2007007617A1 (en) * | 2005-07-08 | 2007-01-18 | Daikin Industries, Ltd. | Surface treatment in presence of organic solvent |
| WO2008059789A1 (en) * | 2006-11-17 | 2008-05-22 | Nippon Mining & Metals Co., Ltd. | Silver-plated fine copper powder, conductive paste produced from silver-plated fine copper powder, and process for producing silver-plated fine copper powder |
| JPWO2008059789A1 (en) * | 2006-11-17 | 2010-03-04 | 日鉱金属株式会社 | Silver-plated copper fine powder, conductive paste produced using silver-plated copper fine powder, and method for producing silver-plated copper fine powder |
| CN100448570C (en) * | 2007-02-01 | 2009-01-07 | 北京化工大学 | Preparation method of nanometer copper-silver bimetallic composite powder |
| JP2010065260A (en) * | 2008-09-09 | 2010-03-25 | Tohoku Univ | Method for producing silver-coated copper fine powder |
| JP2011044509A (en) * | 2009-08-20 | 2011-03-03 | Mitsubishi Materials Corp | Conductive ink composition, and solar cell module formed using the composition |
| JP2013045742A (en) * | 2011-08-26 | 2013-03-04 | Yokohama Rubber Co Ltd:The | Conductive composition, solar cell, and solar cell module |
| CN103890966B (en) * | 2011-10-18 | 2016-10-12 | 迪睿合电子材料有限公司 | Conductive adhesive and use solar module and the manufacture method thereof of this conductive adhesive |
| CN103890966A (en) * | 2011-10-18 | 2014-06-25 | 迪睿合电子材料有限公司 | Conductive adhesive, solar cell module using same, and method for manufacturing solar cell module |
| US10287442B2 (en) | 2011-12-13 | 2019-05-14 | Heraeus Precious Metals North America Conshohocken Llc | Electrically conductive polymeric compositions, contacts, assemblies, and methods |
| JP2017150086A (en) * | 2012-01-17 | 2017-08-31 | Ｄｏｗａエレクトロニクス株式会社 | Silver coated copper alloy powder and manufacturing method therefor |
| JP2013185213A (en) * | 2012-03-08 | 2013-09-19 | Tokyo Institute Of Technology | Metal nanoparticle, method for producing the same, and conductive ink |
| CN105073307B (en) * | 2013-03-28 | 2019-04-19 | 东洋铝株式会社 | Electroconductive particle, its manufacturing method, the conductive resin composition containing it and electric conductivity coating material |
| WO2014156978A1 (en) | 2013-03-28 | 2014-10-02 | 東洋アルミニウム株式会社 | Conductive particles, method for producing same, conductive resin composition containing same, and conductive coated material |
| KR20180132176A (en) | 2013-03-28 | 2018-12-11 | 도요 알루미늄 가부시키가이샤 | Conductive particles, method for producing same, conductive resin composition containing same, and conductive coated material |
| CN105073307A (en) * | 2013-03-28 | 2015-11-18 | 东洋铝株式会社 | Conductive particles, method for producing same, conductive resin composition containing same, and conductive coated material |
| EP2979781B1 (en) * | 2013-03-28 | 2022-02-16 | Toyo Aluminium Kabushiki Kaisha | Conductive particles, method of manufacturing the same, conductive resin composition containing same, and conductive coated object |
| US10020090B2 (en) | 2013-03-28 | 2018-07-10 | Toyo Aluminium Kabushiki Kaisha | Conductive particles, method of manufacturing the same, conductive resin composition containing the same, and conductive coated object |
| KR20210027541A (en) | 2013-03-28 | 2021-03-10 | 도요 알루미늄 가부시키가이샤 | Conductive particles, method for producing same, conductive resin composition containing same, and conductive coated material |
| KR20210104167A (en) | 2013-03-28 | 2021-08-24 | 도요 알루미늄 가부시키가이샤 | Conductive particles, method for producing same, conductive resin composition containing same, and conductive coated material |
| JP2015021145A (en) * | 2013-07-16 | 2015-02-02 | Ｄｏｗａエレクトロニクス株式会社 | Silver-coated copper alloy powder and method for producing the same |
| KR101499141B1 (en) * | 2013-09-06 | 2015-03-11 | 동아대학교 산학협력단 | Conductive Powder, Method for Manufacturing the Same, and Conductive Paste Using the Conductive Powder |
| KR101402437B1 (en) | 2013-10-15 | 2014-06-03 | 한동철 | The method of silver coated flake copper powder used membrane sheet circuit printing conductive paste |
| KR101403371B1 (en) | 2013-12-31 | 2014-06-03 | 충남대학교산학협력단 | Manufacturing method of metal particle and metal particle using thereof, and conductive paste and shielding electromagnetic wave containing the same |
| KR20160102547A (en) | 2014-01-14 | 2016-08-30 | 도요 알루미늄 가부시키가이샤 | Composite conductive particles, conductive resin composition containing same and conductive coated article |
| WO2015107996A1 (en) | 2014-01-14 | 2015-07-23 | 東洋アルミニウム株式会社 | Composite conductive particles, conductive resin composition containing same and conductive coated article |
| US10227496B2 (en) | 2014-01-14 | 2019-03-12 | Toyo Aluminium Kabushiki Kaisha | Composite conductive particle, conductive resin composition containing same and conductive coated article |
| KR20170031210A (en) | 2014-08-26 | 2017-03-20 | 스미토모 긴조쿠 고잔 가부시키가이샤 | Silver-coated copper powder, and conductive paste, conductive coating material and conductive sheet each of which uses same |
| KR20170031215A (en) | 2014-09-12 | 2017-03-20 | 스미토모 긴조쿠 고잔 가부시키가이샤 | Silver-coated copper powder, and conductive paste, conductive coating material and conductive sheet, each of which uses said silver-coated copper powder |
| JP2018509524A (en) * | 2015-01-09 | 2018-04-05 | クラークソン ユニバーシティ | Silver-coated copper flakes and method for producing the same |
| JP2016148073A (en) * | 2015-02-10 | 2016-08-18 | 国立大学法人大阪大学 | Joining method |
| US10654101B2 (en) | 2015-05-15 | 2020-05-19 | Sumitomo Metal Mining Co., Ltd. | Silver-coated copper powder, copper paste using same, conductive coating material, conductive sheet, and method for producing silver-coated copper powder |
| US10695830B2 (en) | 2015-05-15 | 2020-06-30 | Sumitomo Metal Mining Co., Ltd. | Copper powder, copper paste using same, conductive coating material, conductive sheet, and method for producing copper powder |
| US10486231B2 (en) | 2015-08-31 | 2019-11-26 | Mitsui Mining & Smelting Co., Ltd. | Silver-coated copper powder |
| US20170218512A1 (en) * | 2016-02-02 | 2017-08-03 | National Cheng Kung University | Method of Fabricating High-Conductivity Thick-film Copper Paste Coated with Nano-Silver for Being Sintered in the Air |
| JP2020073727A (en) * | 2016-09-29 | 2020-05-14 | Ｊｘ金属株式会社 | Surface-treated metal powder for laser sintering |
| JP7079237B2 (en) | 2016-09-29 | 2022-06-01 | Ｊｘ金属株式会社 | Surface-treated metal powder for laser sintering |
| CN109355034A (en) * | 2018-10-24 | 2019-02-19 | 焦作市高森建电子科技有限公司 | A kind of conducting resinl silver-coated copper powder and preparation method thereof |
| JP7018551B1 (en) * | 2020-08-26 | 2022-02-10 | 三井金属鉱業株式会社 | Silver-coated flake-shaped copper powder and its manufacturing method |
| EP4205886A4 (en) * | 2020-08-26 | 2024-01-24 | Mitsui Mining & Smelting Co Ltd | Silver-coated flake-form copper powder, and method for manufacturing same |
| CN112355322A (en) * | 2020-11-18 | 2021-02-12 | 深圳市夏特科技有限公司 | Preparation device and preparation method of flaky silver-coated copper powder |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4660701B2 (en) | 2011-03-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4660701B2 (en) | Silver-coated copper powder, method for producing the same, and conductive paste | |
| JP5937730B2 (en) | Method for producing copper powder | |
| JP5080731B2 (en) | Fine silver particle-attached silver-copper composite powder and method for producing the fine silver particle-attached silver-copper composite powder | |
| JP5284728B2 (en) | Silver-coated aluminum powder and method for producing the same | |
| JP6813519B2 (en) | Conductive particles, conductive resin compositions and coatings containing them | |
| JP5778941B2 (en) | Method for producing silver-coated flake copper powder | |
| JP5453598B2 (en) | Silver-coated copper powder and conductive paste | |
| JP6186197B2 (en) | Silver-coated copper alloy powder and method for producing the same | |
| WO2006118182A1 (en) | Tin powder, process for producing tin powder, and tin powder-containing elctrically conductive paste | |
| JP2009046708A (en) | Silver powder | |
| JP2016130365A (en) | Silver-coated copper powder and method for producing the same | |
| JP2016139598A (en) | Silver coated copper powder, and copper paste, conductive coating and conductive sheet using the same | |
| JP6567921B2 (en) | Silver-coated copper powder and method for producing the same | |
| JP2007115497A (en) | Nickel-coated copper fine particle, manufacturing method of the same, conductive paste, and manufacturing method of conductive film | |
| JP2016094665A (en) | Silver coated copper powder and conductive paste using the same, conductive coating and conductive sheet | |
| JP2006118032A (en) | Flake copper powder provided with copper oxide coat layer, method for producing flake copper powder provided with copper oxide coat layer and conductive slurry comprising flake copper powder provided with copper oxide coat layer | |
| JP6194166B2 (en) | Method for producing silver-coated copper alloy powder | |
| JP2007191752A (en) | Tin-coated silver powder and method for producing the tin-coated silver powder | |
| WO2015008628A1 (en) | Silver-coated copper alloy powder and process for producing same | |
| JP2007188845A (en) | Conductive powder, conductive paste and electrical circuit | |
| JP2006183110A (en) | Silver-copper composite powder and method for producing silver-copper composite powder | |
| JP5785433B2 (en) | Low carbon copper particles | |
| WO2017179524A1 (en) | Silver-coated copper powder and method for producing same | |
| JP2017201062A (en) | Method for producing silver-coated copper alloy powder | |
| JP2019214748A (en) | Surface-coated metal fine particle and dispersion solution thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20071003 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080218 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20100511 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20100712 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20101116 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20101202 |
|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A712 Effective date: 20101202 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20101202 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20101202 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4660701 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140114 Year of fee payment: 3 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |