WO2017122689A1 - Nickel powder - Google Patents
Nickel powder Download PDFInfo
- Publication number
- WO2017122689A1 WO2017122689A1 PCT/JP2017/000660 JP2017000660W WO2017122689A1 WO 2017122689 A1 WO2017122689 A1 WO 2017122689A1 JP 2017000660 W JP2017000660 W JP 2017000660W WO 2017122689 A1 WO2017122689 A1 WO 2017122689A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- nickel
- nickel powder
- gas
- powder
- spectrum
- Prior art date
Links
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 title claims abstract description 229
- 239000002245 particle Substances 0.000 claims abstract description 56
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 47
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 claims abstract description 27
- 238000001228 spectrum Methods 0.000 claims abstract description 26
- BFDHFSHZJLFAMC-UHFFFAOYSA-L nickel(ii) hydroxide Chemical compound [OH-].[OH-].[Ni+2] BFDHFSHZJLFAMC-UHFFFAOYSA-L 0.000 claims abstract description 20
- 238000000576 coating method Methods 0.000 claims abstract description 18
- 239000001301 oxygen Substances 0.000 claims abstract description 18
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 18
- 229910000480 nickel oxide Inorganic materials 0.000 claims abstract description 17
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims abstract description 17
- 239000011248 coating agent Substances 0.000 claims abstract description 16
- 238000004458 analytical method Methods 0.000 claims abstract description 9
- 239000002344 surface layer Substances 0.000 claims abstract description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 17
- 239000000126 substance Substances 0.000 claims description 7
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 6
- 238000005245 sintering Methods 0.000 abstract description 29
- 230000032798 delamination Effects 0.000 abstract description 19
- 229910052751 metal Inorganic materials 0.000 abstract description 13
- 239000002184 metal Substances 0.000 abstract description 13
- 239000007789 gas Substances 0.000 description 81
- 238000000034 method Methods 0.000 description 37
- 239000000843 powder Substances 0.000 description 34
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 29
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 29
- 238000004519 manufacturing process Methods 0.000 description 20
- 239000003985 ceramic capacitor Substances 0.000 description 19
- 238000010438 heat treatment Methods 0.000 description 18
- 238000006722 reduction reaction Methods 0.000 description 14
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 13
- 238000005259 measurement Methods 0.000 description 13
- 230000003647 oxidation Effects 0.000 description 12
- 238000007254 oxidation reaction Methods 0.000 description 12
- 229910052717 sulfur Inorganic materials 0.000 description 12
- 239000011593 sulfur Substances 0.000 description 12
- 239000012298 atmosphere Substances 0.000 description 11
- 230000000052 comparative effect Effects 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 229910001868 water Inorganic materials 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 230000008859 change Effects 0.000 description 8
- 239000010410 layer Substances 0.000 description 8
- 230000009467 reduction Effects 0.000 description 8
- PPDADIYYMSXQJK-UHFFFAOYSA-N trichlorosilicon Chemical compound Cl[Si](Cl)Cl PPDADIYYMSXQJK-UHFFFAOYSA-N 0.000 description 8
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 7
- 238000011156 evaluation Methods 0.000 description 7
- 230000001590 oxidative effect Effects 0.000 description 7
- 239000002002 slurry Substances 0.000 description 7
- YOUIDGQAIILFBW-UHFFFAOYSA-J tetrachlorotungsten Chemical compound Cl[W](Cl)(Cl)Cl YOUIDGQAIILFBW-UHFFFAOYSA-J 0.000 description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 6
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical compound ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 description 6
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 6
- 239000011230 binding agent Substances 0.000 description 6
- 238000001035 drying Methods 0.000 description 6
- 239000007791 liquid phase Substances 0.000 description 6
- 238000011946 reduction process Methods 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000000919 ceramic Substances 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- FBAFATDZDUQKNH-UHFFFAOYSA-M iron chloride Chemical compound [Cl-].[Fe] FBAFATDZDUQKNH-UHFFFAOYSA-M 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- -1 oxynitrate Chemical compound 0.000 description 5
- 239000012808 vapor phase Substances 0.000 description 5
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 description 4
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 4
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 4
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 4
- 239000011261 inert gas Substances 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 150000002816 nickel compounds Chemical class 0.000 description 4
- 239000003960 organic solvent Substances 0.000 description 4
- 239000002904 solvent Substances 0.000 description 4
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 3
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 239000001856 Ethyl cellulose Substances 0.000 description 3
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 description 3
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 description 3
- XZQYTGKSBZGQMO-UHFFFAOYSA-I Rhenium(V) chloride Inorganic materials Cl[Re](Cl)(Cl)(Cl)Cl XZQYTGKSBZGQMO-UHFFFAOYSA-I 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000010521 absorption reaction Methods 0.000 description 3
- IGODOXYLBBXFDW-UHFFFAOYSA-N alpha-Terpinyl acetate Chemical compound CC(=O)OC(C)(C)C1CCC(C)=CC1 IGODOXYLBBXFDW-UHFFFAOYSA-N 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 3
- 239000010953 base metal Substances 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 229910001882 dioxygen Inorganic materials 0.000 description 3
- 239000002270 dispersing agent Substances 0.000 description 3
- 229920001249 ethyl cellulose Polymers 0.000 description 3
- 235000019325 ethyl cellulose Nutrition 0.000 description 3
- 239000010419 fine particle Substances 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000006479 redox reaction Methods 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- UXMRNSHDSCDMLG-UHFFFAOYSA-J tetrachlororhenium Chemical compound Cl[Re](Cl)(Cl)Cl UXMRNSHDSCDMLG-UHFFFAOYSA-J 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 2
- 229910021555 Chromium Chloride Inorganic materials 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 2
- XYFCBTPGUUZFHI-UHFFFAOYSA-N Phosphine Chemical compound P XYFCBTPGUUZFHI-UHFFFAOYSA-N 0.000 description 2
- 238000000862 absorption spectrum Methods 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- WUOACPNHFRMFPN-UHFFFAOYSA-N alpha-terpineol Chemical compound CC1=CCC(C(C)(C)O)CC1 WUOACPNHFRMFPN-UHFFFAOYSA-N 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- JRPBQTZRNDNNOP-UHFFFAOYSA-N barium titanate Chemical compound [Ba+2].[Ba+2].[O-][Ti]([O-])([O-])[O-] JRPBQTZRNDNNOP-UHFFFAOYSA-N 0.000 description 2
- 229910002113 barium titanate Inorganic materials 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 239000012159 carrier gas Substances 0.000 description 2
- 238000005660 chlorination reaction Methods 0.000 description 2
- QSWDMMVNRMROPK-UHFFFAOYSA-K chromium(3+) trichloride Chemical compound [Cl-].[Cl-].[Cl-].[Cr+3] QSWDMMVNRMROPK-UHFFFAOYSA-K 0.000 description 2
- 230000008602 contraction Effects 0.000 description 2
- ORTQZVOHEJQUHG-UHFFFAOYSA-L copper(II) chloride Chemical compound Cl[Cu]Cl ORTQZVOHEJQUHG-UHFFFAOYSA-L 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- SQIFACVGCPWBQZ-UHFFFAOYSA-N delta-terpineol Natural products CC(C)(O)C1CCC(=C)CC1 SQIFACVGCPWBQZ-UHFFFAOYSA-N 0.000 description 2
- FLKPEMZONWLCSK-UHFFFAOYSA-N diethyl phthalate Chemical compound CCOC(=O)C1=CC=CC=C1C(=O)OCC FLKPEMZONWLCSK-UHFFFAOYSA-N 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012776 electronic material Substances 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- UWKAYLJWKGQEPM-LBPRGKRZSA-N linalyl acetate Chemical compound CC(C)=CCC[C@](C)(C=C)OC(C)=O UWKAYLJWKGQEPM-LBPRGKRZSA-N 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- UODXCYZDMHPIJE-UHFFFAOYSA-N menthanol Chemical compound CC1CCC(C(C)(C)O)CC1 UODXCYZDMHPIJE-UHFFFAOYSA-N 0.000 description 2
- 229910001510 metal chloride Inorganic materials 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- PDKHNCYLMVRIFV-UHFFFAOYSA-H molybdenum;hexachloride Chemical compound [Cl-].[Cl-].[Cl-].[Cl-].[Cl-].[Cl-].[Mo] PDKHNCYLMVRIFV-UHFFFAOYSA-H 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 239000011164 primary particle Substances 0.000 description 2
- 238000005118 spray pyrolysis Methods 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- OEIMLTQPLAGXMX-UHFFFAOYSA-I tantalum(v) chloride Chemical compound Cl[Ta](Cl)(Cl)(Cl)Cl OEIMLTQPLAGXMX-UHFFFAOYSA-I 0.000 description 2
- 229940116411 terpineol Drugs 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 229920002554 vinyl polymer Polymers 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000001716 (4-methyl-1-propan-2-yl-1-cyclohex-2-enyl) acetate Substances 0.000 description 1
- DSSYKIVIOFKYAU-XCBNKYQSSA-N (R)-camphor Chemical compound C1C[C@@]2(C)C(=O)C[C@@H]1C2(C)C DSSYKIVIOFKYAU-XCBNKYQSSA-N 0.000 description 1
- OAYXUHPQHDHDDZ-UHFFFAOYSA-N 2-(2-butoxyethoxy)ethanol Chemical compound CCCCOCCOCCO OAYXUHPQHDHDDZ-UHFFFAOYSA-N 0.000 description 1
- VXQBJTKSVGFQOL-UHFFFAOYSA-N 2-(2-butoxyethoxy)ethyl acetate Chemical compound CCCCOCCOCCOC(C)=O VXQBJTKSVGFQOL-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
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 1
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 description 1
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 241000723346 Cinnamomum camphora Species 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910001111 Fine metal Inorganic materials 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910021607 Silver chloride Inorganic materials 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- FAFMZORPAAGQFV-BREBYQMCSA-N [(1r,3r,4r)-4,7,7-trimethyl-3-bicyclo[2.2.1]heptanyl] propanoate Chemical compound C1C[C@@]2(C)[C@H](OC(=O)CC)C[C@@H]1C2(C)C FAFMZORPAAGQFV-BREBYQMCSA-N 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- DHKHKXVYLBGOIT-UHFFFAOYSA-N acetaldehyde Diethyl Acetal Natural products CCOC(C)OCC DHKHKXVYLBGOIT-UHFFFAOYSA-N 0.000 description 1
- 150000001241 acetals Chemical class 0.000 description 1
- 238000007605 air drying Methods 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 229920000180 alkyd Polymers 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000012300 argon atmosphere Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 230000005587 bubbling Effects 0.000 description 1
- 229960000846 camphor Drugs 0.000 description 1
- 229930008380 camphor Natural products 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 239000002775 capsule Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 150000007942 carboxylates Chemical class 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000007571 dilatometry Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 238000007606 doctor blade method Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 238000010574 gas phase reaction Methods 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- FUZZWVXGSFPDMH-UHFFFAOYSA-M hexanoate Chemical compound CCCCCC([O-])=O FUZZWVXGSFPDMH-UHFFFAOYSA-M 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- DIICMQCJAQLQPI-UHFFFAOYSA-N isobornyl propionate Natural products CCC(=O)C1CC2CCC1(C)C2(C)C DIICMQCJAQLQPI-UHFFFAOYSA-N 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- UWKAYLJWKGQEPM-UHFFFAOYSA-N linalool acetate Natural products CC(C)=CCCC(C)(C=C)OC(C)=O UWKAYLJWKGQEPM-UHFFFAOYSA-N 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 150000002815 nickel Chemical class 0.000 description 1
- XIKYYQJBTPYKSG-UHFFFAOYSA-N nickel Chemical compound [Ni].[Ni] XIKYYQJBTPYKSG-UHFFFAOYSA-N 0.000 description 1
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 1
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 1
- 229910052763 palladium Inorganic materials 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 229910000073 phosphorus hydride Inorganic materials 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000001507 sample dispersion Methods 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 239000011163 secondary particle Substances 0.000 description 1
- 239000005049 silicon tetrachloride Substances 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 239000012798 spherical particle Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 description 1
- CENHPXAQKISCGD-UHFFFAOYSA-N trioxathietane 4,4-dioxide Chemical compound O=S1(=O)OOO1 CENHPXAQKISCGD-UHFFFAOYSA-N 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/16—Metallic particles coated with a non-metal
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B5/00—Non-insulated conductors or conductive bodies characterised by their form
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2301/00—Metallic composition of the powder or its coating
- B22F2301/15—Nickel or cobalt
- B22F2301/155—Rare Earth - Co or -Ni intermetallic alloys
Definitions
- the present invention relates to a nickel powder suitable for use in a conductive paste, and more particularly to a nickel powder excellent in sintering characteristics and dispersibility used for an internal electrode of a multilayer ceramic capacitor.
- noble metal powders such as silver, palladium, platinum, and gold, or base metal powders such as nickel, cobalt, iron, molybdenum, and tungsten are used as conductive pastes for electronic materials, particularly for internal electrodes of multilayer ceramic capacitors.
- dielectric ceramic layers and metal layers used as internal electrodes are alternately stacked, and external electrodes connected to the metal layers of the internal electrodes are connected to both ends of the dielectric ceramic layers. It has a configuration.
- a material constituting the dielectric a material mainly composed of a material having a high dielectric constant such as barium titanate, strontium titanate, yttrium oxide or the like is used.
- the metal constituting the internal electrode the above-mentioned noble metal powder or base metal powder is used, but recently, a cheaper electronic material is required, so the development of a multilayer ceramic capacitor using the latter base metal powder has been developed.
- metallic nickel powder is typical.
- a multilayer ceramic capacitor using metallic nickel powder as an internal electrode is generally manufactured by the following method. That is, a dielectric powder such as barium titanate is mixed and suspended with an organic binder, and this is formed into a sheet by a doctor blade method to produce a dielectric green sheet.
- metallic nickel powder for internal electrodes is mixed with an organic compound such as an organic solvent, a plasticizer, and an organic binder to form a metallic nickel powder paste, which is printed on the green sheet by a screen printing method.
- the temperature is further raised in a reducing atmosphere of hydrogen gas and baked at a temperature of 1000 to 1300 ° C. or higher. External electrodes are baked on both ends of the body ceramic layer to obtain a multilayer ceramic capacitor.
- a heat treatment in which a metal paste is printed on a dielectric green sheet, laminated and pressure-bonded, and then an organic component is removed by heat treatment is usually performed in the atmosphere at 250 to 400. Done at °C. Since the heat treatment is performed in the oxidizing atmosphere in this manner, the metallic nickel powder is oxidized, thereby causing volume expansion. At the same time, the metallic nickel powder begins to sinter and volume shrinkage begins to occur.
- a volume change due to expansion / contraction occurs in the metallic nickel powder by a redox / sintering reaction from a low temperature region around 300 ° C.
- the dielectric layer and the electrode layer are likely to be distorted, resulting in the destruction of the layered structure called cracking or delamination. There was a problem of getting up.
- Patent Document 1 discloses a metallic nickel powder having a tap density with respect to a specific particle size having a certain limit value or more. By using such a metallic nickel powder, a nickel powder dispersed in a paste and a dielectric are used. It is described that delamination hardly occurs when the capacitor is baked.
- Patent Document 1 has a certain effect for improving the sintering behavior, it is not always sufficient as a method for preventing delamination, and further improvement has been desired.
- Patent Document 2 Patent Document 3, and Patent Document 4 disclose nickel powder that can prevent delamination. Specifically, it is a nickel powder obtained by heat treatment in an oxidizing atmosphere at 200 to 400 ° C. and a heat treatment time of 1 minute to 10 hours.
- JP-A-8-246001 JP 2000-0500001 A Japanese Patent Laid-Open No. 2000-045002 International Publication No. WO2004 / 020128
- the present invention exhibits excellent sintering behavior and dispersibility in nickel powder having an average particle size of 250 nm or less used in the production process of a multilayer ceramic capacitor, resulting in delamination.
- An object of the present invention is to provide a nickel powder suitable for a conductive paste that can be prevented. More specifically, the volume change or weight change due to the oxidation-reduction reaction is small during the heat treatment, and the sintering start temperature is higher than that of the conventional nickel powder, so that the dielectric used for manufacturing the multilayer ceramic capacitor is used.
- the object is to provide a nickel powder for a conductive paste that is closer to the sintering start temperature of the body and, as a result, can prevent delamination.
- the present inventors belonged to the binding state of nickel and oxygen in the analysis of the chemical bonding state of nickel on the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS).
- XPS X-ray photoelectron spectroscopy
- the nickel powder of the present invention has a coating containing nickel oxide and nickel hydroxide, has an average particle size of 250 nm or less, and analyzes the chemical bonding state of nickel on the surface layer of the nickel powder by X-ray photoelectron spectroscopy (XPS).
- XPS X-ray photoelectron spectroscopy
- the area ratio of the peak attributed to the bonding state of nickel and oxygen to the entire Ni2p 3/2 spectrum is 55.0 to 80.0%
- the area ratio of the peak of metallic nickel to the entire Ni2p 3/2 spectrum is 5.
- the area ratio of the peak attributed to the bonding state of nickel and hydroxyl group to 0 to 15.0% with respect to the entire Ni2p 3/2 spectrum is 5.0 to 40.0%, and the average thickness of the coating is 3 0.0 to 5.0 nm.
- the nickel powder of the present invention it is possible to provide a nickel powder suitable for a conductive paste that exhibits excellent sintering behavior and dispersibility, and as a result can prevent delamination.
- the number average particle diameter of the nickel powder of the present invention is 250 nm or less. Further, it is preferably 30 to 250 nm, more preferably fine particles in the range of 50 to 250 nm, and more preferably fine particles in the range of 140 to 250 nm.
- the average particle diameter of the nickel powder of the present invention was obtained by taking a photograph of the primary particles of the nickel powder with a scanning electron microscope and measuring the particle diameter of 500 or more particles using image analysis software from the photograph. The number average particle size is calculated from the particle size distribution of the obtained nickel powder. At this time, the particle diameter is the diameter of the smallest circle that encloses the particles.
- the ratio (d / D) of the number average particle diameter D and the specific surface area diameter d of the nickel powder of the present invention is preferably 0.7 or more.
- the specific surface area diameter of the present invention is calculated from the specific surface area of the nickel fine powder assuming that the particles are true spheres. If d / D is 0.7 or more, it is easy to obtain a good paste, the film density of the film obtained by applying the paste is improved, and good sinterability is obtained in the MLCC manufacturing process.
- the specific surface area of the nickel powder by BET is preferably 2 to 30 m 2 / g.
- the particle shape of the nickel powder of the present invention is preferably spherical in order to improve the sintering characteristics and dispersibility.
- the spherical shape of the present invention means that the aspect ratio is 1.2 or less and the circularity coefficient is 0.675 or more.
- the aspect ratio is the ratio of the major axis to the minor axis of the smallest ellipse that encloses the particles.
- the circularity coefficient is a value defined by 4 ⁇ S / (L ⁇ L), where S is the area of the smallest ellipse surrounding the particle and L is the circumference.
- the ratio of the area of the nickel metal peak to the entire Ni2p 3/2 spectrum is 5.0 to 15.0%, and the peak of the Ni2p 3 /
- the area ratio with respect to the entire two spectra is 5.0 to 40.0%.
- it has a coating film containing nickel oxide and nickel hydroxide formed on the surface of the nickel powder of the present invention.
- the average thickness of the coating is 3.0 to 5.0 nm.
- the nickel powder of the present invention has an absorption peak with a wave number of 3600 to 3700 cm ⁇ 1 due to the OH group chemically bonded to metallic nickel when infrared absorption spectrum analysis is performed.
- the nickel powder of the present invention Since the nickel powder of the present invention has a strong nickel oxide and nickel hydroxide coating on the surface, the sintering start temperature is higher than that of the conventional nickel powder, and the dielectric powder used when manufacturing the multilayer ceramic capacitor is used. It is closer to the sintering start temperature of the body. Therefore, the nickel powder of the present invention is superior in oxidation behavior and sintering behavior during heating as compared with conventional nickel powder, so that delamination can be effectively prevented.
- the nickel powder of the present invention has good dispersibility in a solvent such as pure water.
- the entire Ni2p 3/2 spectrum of the present invention is the peak attributed to metallic nickel, the combined state of nickel and oxygen in the analysis of the chemical bonding state of nickel on the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS). It is the spectrum resulting from the peak attributed to and the peak attributed to the bonding state of nickel and a hydroxyl group.
- the area ratio of each spectrum is obtained by peak-separating the obtained Ni2p 3/2 spectrum, calculating the area of each spectrum, and determining the area ratio of each spectrum relative to the sum.
- the thickness of the coating of the present invention is obtained by observing a lattice image of a nickel powder sample with a transmission electron microscope, measuring the film thickness of the nickel powder surface at six points, and calculating the average.
- the area ratio of the peak attributed to the bonding state of nickel and oxygen to the entire Ni2p 3/2 spectrum is 60. 0.0 to 75.0%
- the area ratio of the peak of nickel metal to the entire Ni2p 3/2 spectrum is 7.0 to 13.0%
- the area ratio with respect to the thickness is 12.0 to 33.0%
- the average thickness of the nickel oxide and nickel hydroxide coatings is 3.5 to 4.5 nm.
- the nickel powder of the present invention can be produced by a known method such as a gas phase method or a liquid phase method.
- a gas phase method such as a gas phase method or a liquid phase method.
- the vapor phase reduction method in which nickel powder is produced by bringing nickel chloride gas into contact with a reducing gas, or the spray pyrolysis method in which a thermally decomposable nickel compound is sprayed to thermally decompose is used to produce fine metal powder. It is preferable in that the particle size can be easily controlled, and spherical particles can be efficiently produced.
- the vapor phase reduction method in which nickel chloride gas is brought into contact with a reducing gas is preferable from the viewpoint that the particle diameter of the produced nickel powder can be precisely controlled and the generation of coarse particles can be prevented.
- vaporized nickel chloride gas is reacted with a reducing gas such as hydrogen.
- nickel chloride gas may be generated by heating and evaporating solid nickel chloride.
- the metal chloride is brought into contact with chlorine gas to continuously generate nickel chloride gas, and this nickel chloride gas is directly supplied to the reduction process and then reduced. It is advantageous to produce nickel fine powder by contacting nickel chloride gas and continuously reducing nickel chloride gas.
- the vapor phase reduction method can obtain nickel powder having a ratio of the number average particle diameter D to the crystallite diameter d (d / D) of 0.40 or more with a high yield.
- Metal chloride gases other than nickel chloride gas when used in a method for producing an alloy powder containing nickel as a main component are silicon trichloride (III) gas, silicon tetrachloride (IV) gas, monosilane gas, copper chloride (I ) Gas, copper chloride (II) gas, silver chloride gas, molybdenum chloride gas (III) gas, molybdenum chloride (V) gas, iron chloride (II) gas, iron chloride (III) gas, chromium chloride (III) gas, Chromium chloride (VI) gas, tungsten chloride (II) gas, tungsten chloride (III) gas, tungsten chloride (IV) gas, tungsten chloride (V) gas, tungsten chloride (VI) gas, tantalum chloride (III) gas, chloride Tantalum (V) gas, cobalt chloride gas, rhenium chloride (III) gas, rhenium chloride (IV) gas, rhenium chloride (V
- examples of the reducing gas include hydrogen gas, hydrogen sulfide gas, ammonia gas, carbon monoxide gas, methane gas, and a mixed gas thereof. Particularly preferred are hydrogen gas, hydrogen sulfide gas, ammonia gas, and mixed gas thereof.
- nickel atoms are generated at the moment when the nickel chloride gas and the reducing gas come into contact with each other, and nickel particles collide and agglomerate to generate and grow nickel particles.
- the particle diameter of the nickel powder to be generated is determined by conditions such as the partial pressure and temperature of the nickel chloride gas in the reduction step. According to the nickel powder manufacturing method as described above, an amount of nickel chloride gas corresponding to the supply amount of chlorine gas is generated. Therefore, the amount of nickel chloride gas supplied to the reduction process is controlled by controlling the supply amount of chlorine gas. The amount can be adjusted, thereby controlling the particle size of the nickel powder produced.
- nickel chloride gas is generated by the reaction of chlorine gas and metal, unlike the method of generating nickel chloride gas by heating evaporation of solid nickel chloride, not only can the use of carrier gas be reduced. Depending on the manufacturing conditions, it is possible not to use them. Therefore, in the gas phase reduction reaction, the production cost can be reduced by reducing the amount of carrier gas used and the accompanying reduction in heating energy.
- the partial pressure of nickel chloride gas in the reduction process can be controlled by mixing an inert gas with the nickel chloride gas generated in the chlorination process.
- the particle size of nickel powder can be controlled, and variation in particle size can be suppressed,
- the particle size can be arbitrarily set.
- nickel chloride as a starting material is made by reacting metallic nickel having a purity of 99.5% or more in the form of particles, lumps, plates, etc. with chlorine gas to generate nickel chloride gas.
- the temperature is set to 800 ° C. or higher for sufficient progress of the reaction, and 1453 ° C. or lower, which is the melting point of nickel.
- the range of 900 ° C. to 1100 ° C. is preferable for practical use.
- this nickel chloride gas is directly supplied to the reduction process and brought into contact with a reducing gas such as hydrogen gas.
- the partial pressure of the nickel chloride gas can be controlled by appropriately diluting the nickel chloride gas with an inert gas such as argon or nitrogen.
- an inert gas such as argon or nitrogen.
- the temperature of the reduction reaction may be at least the temperature sufficient for completion of the reaction, preferably below the melting point of nickel, and practically 900 ° C. to 1100 ° C. in view of economy.
- the generated nickel powder is cooled.
- a reduction reaction is performed by blowing an inert gas such as nitrogen gas. It is desirable to rapidly cool the finished gas flow around 1000 ° C. to about 400 to 800 ° C. Thereafter, the produced nickel powder is separated and collected by, for example, a bag filter or the like.
- a heat decomposable nickel compound is used as a raw material. Specifically, one or more of nitrate, sulfate, oxynitrate, oxysulfate, chloride, ammonium complex, phosphate, carboxylate, alkoxy compound and the like are included.
- the solution containing the nickel compound is sprayed to form fine droplets.
- water, alcohol, acetone, ether or the like is used as the solvent at this time.
- the spraying method is performed by a spraying method such as ultrasonic or double jet nozzle. In this way, fine droplets are formed and heated at a high temperature to thermally decompose the metal compound to produce nickel powder.
- the heating temperature at this time is equal to or higher than the temperature at which the specific nickel compound used is thermally decomposed, and is preferably near the melting point of the metal.
- nickel hydroxide containing nickel sulfate, nickel chloride or a nickel complex is brought into contact by adding it to an alkali metal hydroxide such as sodium hydroxide. Then, the nickel hydroxide is reduced with a reducing agent such as hydrazine to obtain metallic nickel powder. The nickel metal powder thus produced is crushed as necessary to obtain uniform particles.
- the nickel powder obtained by the above method is preferably dispersed and washed in the liquid phase in order to remove the remaining raw material.
- the nickel powder obtained by the above method is suspended in a carbonic acid aqueous solution under specific conditions with controlled pH and temperature.
- impurities such as chlorine adhering to the surface of the nickel powder are sufficiently removed, and oxides such as nickel oxide and nickel hydroxide such as nickel hydroxide existing on the surface of the nickel powder are removed. Fine particles formed away from the surface due to friction between objects and particles are removed, and a thin and uniform film made of nickel oxide and nickel hydroxide can be re-formed by dissolved oxygen in water.
- a treatment method with a carbonic acid aqueous solution a method in which nickel powder and a carbonic acid aqueous solution are mixed, or carbon dioxide gas is blown into a water slurry after the nickel powder is once washed with pure water, or the nickel powder is once washed with pure water.
- the aqueous slurry can be treated by adding an aqueous carbonate solution.
- the method for incorporating sulfur into the nickel powder of the present invention is not particularly limited, and for example, the following method can be employed.
- (1) Method of adding sulfur-containing gas during the reduction reaction (2) Method of contacting nickel powder with sulfur-containing gas (3) Method of mixing nickel powder and solid sulfur-containing compound in a dry process (4) Nickel Method of adding sulfur-containing compound solution in slurry in which powder is dispersed in liquid phase (5) Method of bubbling sulfur-containing gas in slurry in which nickel powder is dispersed in liquid phase
- the methods (1) and (4) are preferable from the viewpoint that the sulfur content can be precisely controlled and sulfur can be added uniformly.
- the sulfur-containing gas used in the methods (1), (2), and (5) is not particularly limited, and is a gas at the temperature of the reduction process, such as sulfur vapor, sulfur dioxide gas, and hydrogen sulfide gas. A certain gas can be used as it is or after being diluted. Of these, sulfur dioxide gas and hydrogen sulfide gas are advantageous because they are gases at room temperature and the flow rate can be easily controlled and impurities are less likely to be mixed.
- the nickel powder slurry is dried after the aforementioned washing step and sulfur addition step.
- the drying method is not particularly limited, and a known method can be used. Specific examples include air-flow drying, drying by heating, and vacuum drying that are brought into contact with a high-temperature gas to dry. Among these, air drying is preferable because there is no destruction of the sulfur-containing layer due to collision between particles.
- the nickel powder obtained as described above is subjected to an oxidation treatment under specific conditions.
- an atmosphere containing an oxidizing gas for example, oxygen gas or ozone gas
- an atmosphere containing an oxidizing gas for example, oxygen gas or ozone gas
- an inert gas containing oxygen gas nitrogen, argon, etc.
- the optimum heat treatment temperature at this time varies depending on the particle diameter, but is preferably 140 to 180 ° C. when the average particle diameter is 250 nm or less used in the production process of the multilayer ceramic capacitor, and particularly in the air when the average particle diameter is 140 to 250 nm.
- the temperature is preferably maintained at 160 to 180 ° C for 1 minute to 4 hours.
- the area ratio of the peak attributed to the bonding state of nickel and oxygen to the entire Ni2p 3/2 spectrum is 55.0 to 80
- the heat treatment conditions are adjusted as appropriate so that the area ratio of the nickel nickel peak to the entire Ni2p 3/2 spectrum is 5.0 to 15.0%. In this way, a stronger nickel oxide film is formed by oxidizing nickel powder.
- the nickel powder of the present invention can be used as a paste raw material. More preferably, it is a nickel paste containing the nickel powder and an organic solvent. Further, if necessary, an organic binder such as ethyl cellulose, a dispersant, and an unfired powder of the ceramic to be coated may be included.
- This nickel paste is added to the above nickel powder, for example, an organic solvent such as terpineol, an organic binder such as ethyl cellulose, a dispersant, and an unfired ceramic powder to be applied, if necessary, and kneaded with three rolls.
- an organic solvent such as terpineol
- an organic binder such as ethyl cellulose
- a dispersant such as ethyl cellulose
- an unfired ceramic powder to be applied, if necessary, and kneaded with three rolls.
- Organic solvents include alcohol, acetone, propanol, ethyl acetate, butyl acetate, ether, petroleum ether, mineral spirit, other paraffinic hydrocarbon solvents, or butyl carbitol, terpineol, dihydroterpineol, butyl carbitol acetate, dihydro Propionate solvents such as terpineol acetate, dihydrocarbyl acetate, carbyl acetate, terpinyl acetate, linalyl acetate, etc., dihydroterpinyl propionate, dihydrocarbyl propionate, isobornyl propionate, Examples include cellosolves such as ethyl cellosolve and butyl cellosolve, aromatics, and diethyl phthalate.
- the organic binder is preferably a resin binder, and examples thereof include ethyl cellulose, polyvinyl acetal, acrylic resin, alkyd resin, and the like.
- the dispersant a known appropriate one can be used, and for example, a vinyl polymer, a polycarboxylic acid amine salt, a polycarboxylic acid type, or the like can be used.
- the production process of the multilayer ceramic capacitor Exhibits excellent sintering behavior and prevents the occurrence of delamination. More specifically, when the heat treatment is performed, the volume change or weight change due to the oxidation-reduction reaction is small, and the sintering start temperature is higher than that of the conventional nickel powder, so that a multilayer ceramic capacitor is manufactured. It becomes closer to the sintering start temperature of the dielectric used at the time, and as a result, generation of delamination can be effectively prevented.
- Example 1 After the gas phase reaction method in which nickel chloride and hydrogen are reacted, washing is performed in pure water and an aqueous carbonate solution, and a sulfur-containing compound solution is added to a slurry in which nickel powder is dispersed in a liquid phase, followed by drying. Nickel powder was prepared. It was confirmed that the obtained nickel powder was a spherical nickel powder having a number average particle diameter of 191 nm, an average aspect ratio of 1.2, and an average circularity coefficient of 0.68. Moreover, the specific surface area was 4.0 m ⁇ 2 > / g and the specific surface area diameter was 168 nm. Further, the ratio d / D of the number average particle diameter d and the specific surface area diameter was 0.88.
- the nickel powder was oxidized at 175 ° C. for 4 hours in an oxidizing atmosphere to obtain nickel powder.
- Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
- Example 1 A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was performed at 155 ° C. for 2 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
- XPS X-ray photoelectron spectroscopy
- Example 2 A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was not performed to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
- XPS X-ray photoelectron spectroscopy
- Example 3 A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was performed at 230 ° C. for 2 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
- XPS X-ray photoelectron spectroscopy
- Oxygen content average particle diameter, nickel metal and surface oxide by surface X-ray photoelectron spectroscopy (XPS), surface hydroxide ratio, dispersibility evaluation, oxidation
- XPS surface X-ray photoelectron spectroscopy
- the method for measuring the thickness of the nickel and nickel hydroxide coatings and the 2% heat shrinkage temperature is shown below.
- Oxygen content The nickel powder of the sample is filled in a nickel capsule, put in a graphite crucible, heated to 500 ° C. in an argon atmosphere, and the carbon monoxide generated at this time is Fourier-transform infrared spectrophotometric. It quantified with the meter and calculated
- Nickel powder was directly sprinkled on a copper sheet mesh covered with a collodion film, and then carbon was deposited to prepare a measurement sample.
- a transmission electron microscope manufactured by JEOL Ltd., JEM-2100F
- the lattice image of the measurement sample was observed under the condition of an acceleration voltage of 200 kV, and the film thicknesses of nickel oxide and nickel hydroxide on the surface of the nickel powder were measured. Six points were measured and the average was calculated.
- 2% heat shrinkage temperature and sintering behavior 1 g of nickel powder, 3% by weight of camphor and 3% by weight of acetone are mixed and filled into a cylindrical mold having an inner diameter of 5 mm and a length of 10 mm.
- a test piece was prepared by applying a load of tons. Using this test piece, a thermal dilatometry measuring device (TMA, 8310, manufactured by Rigaku Co., Ltd.), under a nitrogen gas atmosphere (containing 2% hydrogen gas), a temperature rising rate of 10 ° C./min. The measurement was performed. Further, the temperature of 2% heat shrinkage measured by a thermal expansion / shrinkage behavior measuring apparatus (TMA) was defined as 2% heat shrinkage temperature.
- TMA thermal expansion / shrinkage behavior measuring apparatus
- the nickel powder of Example 1 having a higher surface oxide ratio than the nickel powders of Comparative Examples 1 and 2 is more dispersed than the nickel powder of Comparative Example 3 having a higher surface oxide ratio.
- the sex evaluation was excellent. From this, since the nickel powder of Example 1 is excellent in dispersibility, it is presumed that mixing of the nickel powder and the common material becomes sufficient when the multilayer ceramic capacitor is manufactured, and delamination is prevented.
- the thickness of the nickel powder coating of Example 1 is larger than that of Comparative Examples 1 and 2.
- the nickel powder of Example 1 is higher than the nickel powders of Comparative Examples 1 and 2, and the volume change in the low temperature region of 300 to 400 ° C. is completely observed in the sintering behavior of FIG. Sintering behavior is stable.
- the nickel powder of the present invention exhibits excellent sintering behavior in the production process of the multilayer ceramic capacitor and is excellent in dispersibility, and as a result, prevention of delamination can be achieved.
- the sintering behavior is very stable as compared with the conventional nickel powder at an average particle size of 250 nm or less, and the shrinkage and expansion of the nickel powder in the low temperature region.
- the paste using the nickel powder of the present invention has an effect of preventing the occurrence of delamination in the manufacturing process of the multilayer ceramic capacitor.
- the sintering behavior is very stable compared to the conventional nickel powder, there is no shrinkage and expansion of the nickel powder in the low temperature region, and the dispersibility is excellent.
- a suitable nickel powder can be provided.
Landscapes
- Powder Metallurgy (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Ceramic Capacitors (AREA)
- Non-Insulated Conductors (AREA)
Abstract
[Problem] To provide a nickel powder suitable for use in electroconductive pastes which exhibits excellent sintering behavior and dispersibility and, as a result, can prevent delamination. [Solution] The nickel powder has a coating film comprising nickel oxide and nickel hydroxide and has an average particle diameter of 250 nm or smaller. In analysis by X-ray photoelectron spectroscopy (XPS) for the chemically bonded states of the nickel contained in the surface layer of the nickel powder, the areal proportion of the peak assigned to nickel/oxygen bonding to the whole Ni2p3/2 spectrum is 55.0-80.0%, the areal proportion of the peak assigned to nickel metal to the whole Ni2p3/2 spectrum is 5.0-15.0%, and the areal proportion of the peak assigned to nickel/hydroxy group bonding to the whole Ni2p3/2 spectrum is 5.0-40.0%. The coating film has an average thickness of 3.0-5.0 nm.
Description
本発明は、導電ペースト用に用いて好適なニッケル粉末に係り、特に、積層セラミックコンデンサの内部電極に用いられる焼結特性及び分散性に優れたニッケル粉末に関する。
The present invention relates to a nickel powder suitable for use in a conductive paste, and more particularly to a nickel powder excellent in sintering characteristics and dispersibility used for an internal electrode of a multilayer ceramic capacitor.
従来、銀、パラジウム、白金、金等の貴金属粉末、あるいはニッケル、コバルト、鉄、モリブデン、タングステン等の卑金属粉末は、電子材料用として導電ペースト、特に積層セラミックコンデンサの内部電極用として用いられている。一般に積層セラミックコンデンサは、誘電体セラミック層と、内部電極として使用される金属層とが交互に重ねられ、誘電体セラミック層の両端に、内部電極の金属層に接続される外部電極が接続された構成となっている。ここで、誘電体を構成する材料としては、チタン酸バリウム、チタン酸ストロンチウム、酸化イットリウム等の誘電率の高い材料を主成分とするものが用いられている。一方、内部電極を構成する金属としては、前述した貴金属粉末あるいは卑金属粉末が用いられるが、最近はより安価な電子材料が要求されているため、後者の卑金属粉末を利用した積層セラミックコンデンサの開発が盛んに行われており、特に金属ニッケル粉末が代表的である。
Conventionally, noble metal powders such as silver, palladium, platinum, and gold, or base metal powders such as nickel, cobalt, iron, molybdenum, and tungsten are used as conductive pastes for electronic materials, particularly for internal electrodes of multilayer ceramic capacitors. . In general, in a multilayer ceramic capacitor, dielectric ceramic layers and metal layers used as internal electrodes are alternately stacked, and external electrodes connected to the metal layers of the internal electrodes are connected to both ends of the dielectric ceramic layers. It has a configuration. Here, as a material constituting the dielectric, a material mainly composed of a material having a high dielectric constant such as barium titanate, strontium titanate, yttrium oxide or the like is used. On the other hand, as the metal constituting the internal electrode, the above-mentioned noble metal powder or base metal powder is used, but recently, a cheaper electronic material is required, so the development of a multilayer ceramic capacitor using the latter base metal powder has been developed. In particular, metallic nickel powder is typical.
ところで、金属ニッケル粉末を内部電極として用いた積層セラミックコンデンサは、一般に次のような方法で製造されている。すなわち、チタン酸バリウム等の誘電体粉末を有機バインダーと混合し懸濁させ、これをドクターブレード法によりシート状に成形して誘電体グリーンシートを作成する。一方、内部電極用の金属ニッケル粉末を有機溶剤、可塑剤、有機バインダー等の有機化合物と混合して金属ニッケル粉末ペーストを形成し、これを前記グリーンシート上にスクリーン印刷法で印刷する。次いで、乾燥、積層および圧着し、加熱処理にて有機成分を除去してから、水素ガスの還元性雰囲気においてさらに昇温して１０００～１３００℃またはそれ以上の温度で焼成し、この後、誘電体セラミック層の両端に外部電極を焼き付けて積層セラミックコンデンサを得る。
Incidentally, a multilayer ceramic capacitor using metallic nickel powder as an internal electrode is generally manufactured by the following method. That is, a dielectric powder such as barium titanate is mixed and suspended with an organic binder, and this is formed into a sheet by a doctor blade method to produce a dielectric green sheet. On the other hand, metallic nickel powder for internal electrodes is mixed with an organic compound such as an organic solvent, a plasticizer, and an organic binder to form a metallic nickel powder paste, which is printed on the green sheet by a screen printing method. Next, after drying, laminating and pressure bonding, removing organic components by heat treatment, the temperature is further raised in a reducing atmosphere of hydrogen gas and baked at a temperature of 1000 to 1300 ° C. or higher. External electrodes are baked on both ends of the body ceramic layer to obtain a multilayer ceramic capacitor.
上記のような積層セラミックコンデンサの製造方法において、誘電体グリーンシートに金属ペーストを印刷し、積層及び圧着した後、加熱処理にて有機成分を蒸発除去する加熱処理は、通常大気中で２５０～４００℃で行われる。このように酸化雰囲気中で加熱処理を行うため、金属ニッケル粉末は酸化され、それにより体積の膨張が起きる。同時に金属ニッケル粉末は焼結を開始し体積の収縮が起り始める。
In the method for manufacturing a multilayer ceramic capacitor as described above, a heat treatment in which a metal paste is printed on a dielectric green sheet, laminated and pressure-bonded, and then an organic component is removed by heat treatment is usually performed in the atmosphere at 250 to 400. Done at ℃. Since the heat treatment is performed in the oxidizing atmosphere in this manner, the metallic nickel powder is oxidized, thereby causing volume expansion. At the same time, the metallic nickel powder begins to sinter and volume shrinkage begins to occur.
このように、積層セラミックコンデンサを製造する工程において、３００℃付近の低温領域から酸化還元・焼結反応により金属ニッケル粉末に膨張・収縮による体積変化が生じる。このとき低温段階で金属ニッケル粉末の酸化挙動また焼結挙動が不安定であると、誘電体層と電極層に歪が生じやすく、結果としてクラックまたは剥離などのデラミネーションといわれる層状構造の破壊が起きるという問題があった。
Thus, in the process of manufacturing a multilayer ceramic capacitor, a volume change due to expansion / contraction occurs in the metallic nickel powder by a redox / sintering reaction from a low temperature region around 300 ° C. At this time, if the oxidation behavior or sintering behavior of the metallic nickel powder is unstable at a low temperature stage, the dielectric layer and the electrode layer are likely to be distorted, resulting in the destruction of the layered structure called cracking or delamination. There was a problem of getting up.
上記のようなデラミネーションの問題を解決する手段として種々の方法が提案されている。例えば、特許文献１では、特定の粒径に対するタップ密度がある限界値以上を有する金属ニッケル粉末を開示し、このような金属ニッケル粉末を用いることによって、ペーストに分散されたニッケル粉末と誘電体を焼成してコンデンサとしたときに、デラミネーションが起りにくいことが記載されている。
Various methods have been proposed as means for solving the above delamination problem. For example, Patent Document 1 discloses a metallic nickel powder having a tap density with respect to a specific particle size having a certain limit value or more. By using such a metallic nickel powder, a nickel powder dispersed in a paste and a dielectric are used. It is described that delamination hardly occurs when the capacitor is baked.
しかしながら、特許文献１では焼結挙動を改善する目的としてはそれなりの効果を上げているが、必ずしもデラミネーションを防止する方法としては十分ではなく、さらなる改善が望まれていた。
However, although Patent Document 1 has a certain effect for improving the sintering behavior, it is not always sufficient as a method for preventing delamination, and further improvement has been desired.
また、特許文献２、特許文献３、特許文献４では、デラミネーションを防止できるニッケル粉末が開示されている。具体的には、酸化性雰囲気下２００～４００℃、加熱処理時間は１分～１０時間で熱処理を行うことによって得られるニッケル粉末である。
Patent Document 2, Patent Document 3, and Patent Document 4 disclose nickel powder that can prevent delamination. Specifically, it is a nickel powder obtained by heat treatment in an oxidizing atmosphere at 200 to 400 ° C. and a heat treatment time of 1 minute to 10 hours.
しかしながら、この方法では、２５０ｎｍより細かい粒径においては急激な酸化が発生し、酸素含有量が増大、ニッケル粉末の凝集が増加する。このため、還元雰囲気中で焼成する際、ニッケル粉酸化物の還元によるガス発生と体積変化が大きくなるため、緻密な電極膜が得られなくなるとともに、積層電子部品のクラックやデラミネーションを引き起こす問題や凝集したニッケル粉末により共材との混合が不十分となり、デラミネーションを引き起こす問題が発生する。
However, in this method, rapid oxidation occurs at a particle size smaller than 250 nm, the oxygen content increases, and the aggregation of nickel powder increases. For this reason, when firing in a reducing atmosphere, gas generation and volume change due to reduction of the nickel powder oxide become large, so that a dense electrode film cannot be obtained, and problems such as cracking and delamination of laminated electronic components The agglomerated nickel powder results in insufficient mixing with the co-material and causes delamination.
従って、本発明は、上記従来技術の問題点を鑑み、積層セラミックコンデンサの製造工程で用いられる平均粒径２５０ｎｍ以下のニッケル粉末において、優れた焼結挙動と分散性を示し、結果としてデラミネーションを防止することができる導電ペースト用に適したニッケル粉末を提供することを目的としている。より具体的には、加熱処理した際に、酸化還元反応による体積変化あるいは重量変化が少なく、さらに焼結開始温度が従来のニッケル粉末に比べてより高く、積層セラミックコンデンサを製造する際に用いる誘電体の焼結開始温度により近く、その結果、デラミネーションを防止することができる導電ペースト用ニッケル粉末を提供することを目的としている。
Therefore, in view of the above-mentioned problems of the prior art, the present invention exhibits excellent sintering behavior and dispersibility in nickel powder having an average particle size of 250 nm or less used in the production process of a multilayer ceramic capacitor, resulting in delamination. An object of the present invention is to provide a nickel powder suitable for a conductive paste that can be prevented. More specifically, the volume change or weight change due to the oxidation-reduction reaction is small during the heat treatment, and the sintering start temperature is higher than that of the conventional nickel powder, so that the dielectric used for manufacturing the multilayer ceramic capacitor is used. The object is to provide a nickel powder for a conductive paste that is closer to the sintering start temperature of the body and, as a result, can prevent delamination.
前述のとおり、積層セラミックコンデンサを製造する工程において、酸化還元反応によりニッケル粉末に膨張・収縮による体積変化が生じ、これにより、デラミネーションが生じる。したがって、ニッケル粉末の表面に緻密で厚い酸化被膜が形成されていれば、ニッケル粉末表面から内部への酸化の進行が抑制される。
As described above, in the process of manufacturing the multilayer ceramic capacitor, a volume change due to expansion / contraction occurs in the nickel powder due to the oxidation-reduction reaction, thereby causing delamination. Therefore, if a dense and thick oxide film is formed on the surface of the nickel powder, the progress of oxidation from the nickel powder surface to the inside is suppressed.
そこで、本発明者等は、金属ニッケル粉末について鋭意研究を重ねた結果、Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、ニッケルと酸素の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトルピーク全体に対する面積比により焼結挙動が変わり、特定の方法により製造され、特定の酸化被膜を有する金属ニッケル粉末が焼結特性に優れていることを見出し、本発明を完成するに至った。
Therefore, as a result of intensive research on metallic nickel powders, the present inventors belonged to the binding state of nickel and oxygen in the analysis of the chemical bonding state of nickel on the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS). The sintering behavior varies depending on the area ratio of the peak to the entire Ni2p 3/2 spectral peak, and it has been found that metallic nickel powder produced by a specific method and having a specific oxide film has excellent sintering characteristics. The invention has been completed.
すなわち、本発明のニッケル粉末は、酸化ニッケル及び水酸化ニッケルを含む被膜を有し、平均粒径が２５０ｎｍ以下、Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、ニッケルと酸素の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５５．０～８０．０％、金属ニッケルのピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～１５．０％、ニッケルと水酸基の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～４０．０％であって、前記被膜の厚さの平均が３．０～５．０ｎｍであることを特徴とする。
That is, the nickel powder of the present invention has a coating containing nickel oxide and nickel hydroxide, has an average particle size of 250 nm or less, and analyzes the chemical bonding state of nickel on the surface layer of the nickel powder by X-ray photoelectron spectroscopy (XPS). , The area ratio of the peak attributed to the bonding state of nickel and oxygen to the entire Ni2p 3/2 spectrum is 55.0 to 80.0%, and the area ratio of the peak of metallic nickel to the entire Ni2p 3/2 spectrum is 5. The area ratio of the peak attributed to the bonding state of nickel and hydroxyl group to 0 to 15.0% with respect to the entire Ni2p 3/2 spectrum is 5.0 to 40.0%, and the average thickness of the coating is 3 0.0 to 5.0 nm.
本発明のニッケル粉末によれば、優れた焼結挙動と分散性を示し、結果としてデラミネーションを防止することができる導電ペースト用に適したニッケル粉末を提供することができる。
According to the nickel powder of the present invention, it is possible to provide a nickel powder suitable for a conductive paste that exhibits excellent sintering behavior and dispersibility, and as a result can prevent delamination.
本発明のニッケル粉末の個数平均粒径は、２５０ｎｍ以下である。更に、３０～２５０ｎｍであることが好ましく、５０～２５０ｎｍの範囲の微粒子であればさらに好ましく、１４０～２５０ｎｍの範囲の微粒子であれば、より好適である。なお、本発明のニッケル粉末の平均粒径は、走査電子顕微鏡によりニッケル粉末の一次粒子の写真を撮影し、その写真から画像解析ソフトを使用して、粒子５００個以上の粒径を測定し、得られたニッケル粉末の粒度分布より、その個数平均粒径を算出したものである。このとき、粒径は粒子を包み込む最小円の直径である。
The number average particle diameter of the nickel powder of the present invention is 250 nm or less. Further, it is preferably 30 to 250 nm, more preferably fine particles in the range of 50 to 250 nm, and more preferably fine particles in the range of 140 to 250 nm. In addition, the average particle diameter of the nickel powder of the present invention was obtained by taking a photograph of the primary particles of the nickel powder with a scanning electron microscope and measuring the particle diameter of 500 or more particles using image analysis software from the photograph. The number average particle size is calculated from the particle size distribution of the obtained nickel powder. At this time, the particle diameter is the diameter of the smallest circle that encloses the particles.
また、本発明のニッケル粉の個数平均粒子径Ｄと比表面積径ｄの比（ｄ／Ｄ）は０．７以上が好ましい。本発明の比表面積径とは、粒子を真球と仮定してニッケル微粉の比表面積から計算したものである。ｄ／Ｄが０，７以上であれば、良好なペーストが得やすく、ペーストを塗布することによって得られる膜の膜密度が良くなり、ＭＬＣＣの製造工程において、良好な焼結性となる。
Further, the ratio (d / D) of the number average particle diameter D and the specific surface area diameter d of the nickel powder of the present invention is preferably 0.7 or more. The specific surface area diameter of the present invention is calculated from the specific surface area of the nickel fine powder assuming that the particles are true spheres. If d / D is 0.7 or more, it is easy to obtain a good paste, the film density of the film obtained by applying the paste is improved, and good sinterability is obtained in the MLCC manufacturing process.
また、ニッケル粉末のＢＥＴによる比表面積は、２～３０ｍ２／ｇであることが好ましい。
The specific surface area of the nickel powder by BET is preferably 2 to 30 m 2 / g.
さらに、本発明のニッケル粉末の粒子形状は、球状であることが焼結特性また分散性を向上させるために望ましい。本発明の球状とは、アスペクト比が１．２以下、円形度係数が０．６７５以上であることをいう。アスペクト比は、粒子を包み込む最小楕円の長径と短径の比である。また、円形度係数とは、粒子を囲む最小楕円の面積をＳ、周囲長をＬとしたとき、４πＳ／（Ｌ×Ｌ）で定義される値である。また、ニッケル粉末の形状が球状であることにより、ＭＬＣＣの内部電極に加工した際に充填率が高くなるとともに平坦性が良好となり、クラックとデラミネーションを抑制できる。
Furthermore, the particle shape of the nickel powder of the present invention is preferably spherical in order to improve the sintering characteristics and dispersibility. The spherical shape of the present invention means that the aspect ratio is 1.2 or less and the circularity coefficient is 0.675 or more. The aspect ratio is the ratio of the major axis to the minor axis of the smallest ellipse that encloses the particles. The circularity coefficient is a value defined by 4πS / (L × L), where S is the area of the smallest ellipse surrounding the particle and L is the circumference. Further, since the shape of the nickel powder is spherical, when the MLCC is processed into an internal electrode of the MLCC, the filling rate is increased and the flatness is improved, and cracks and delamination can be suppressed.
本発明のニッケル粉末は、Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、ニッケルと酸素の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５５．０～８０．０％、金属ニッケルのピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～１５．０％、ニッケルと水酸基の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～４０．０％である。換言すると、本発明のニッケル粉末の表面に形成された酸化ニッケル及び水酸化ニッケルを含む被膜を有する。この被膜の厚さの平均は３．０～５．０ｎｍである。
In the nickel powder of the present invention, the area of the peak attributed to the bonding state of nickel and oxygen with respect to the entire Ni2p 3/2 spectrum in the analysis of the chemical bonding state of nickel on the surface layer of the nickel powder by X-ray photoelectron spectroscopy (XPS). The ratio of the area of the nickel metal peak to the entire Ni2p 3/2 spectrum is 5.0 to 15.0%, and the peak of the Ni2p 3 / The area ratio with respect to the entire two spectra is 5.0 to 40.0%. In other words, it has a coating film containing nickel oxide and nickel hydroxide formed on the surface of the nickel powder of the present invention. The average thickness of the coating is 3.0 to 5.0 nm.
さらに、本発明のニッケル粉末は、赤外線吸収スペクトル分析を行うと、金属ニッケルに化学的に結合するＯＨ基に起因する波数が３６００～３７００ｃｍ－１の吸収ピークを有するものである。
Furthermore, the nickel powder of the present invention has an absorption peak with a wave number of 3600 to 3700 cm −1 due to the OH group chemically bonded to metallic nickel when infrared absorption spectrum analysis is performed.
このように特定の厚さの緻密な酸化ニッケル及び水酸化ニッケル被膜を形成していることによって、加熱処理した際に、特に、積層セラミックコンデンサの製造工程で有機成分除去のための３００～４００℃の温度域で加熱された際に、ニッケルの酸化還元による体積および重量の変化を少なく抑えることが可能となる。
By forming a dense nickel oxide and nickel hydroxide film having a specific thickness in this way, when heat treatment is performed, particularly at 300 to 400 ° C. for removing organic components in the production process of the multilayer ceramic capacitor. When heated in this temperature range, changes in volume and weight due to oxidation and reduction of nickel can be minimized.
本発明のニッケル粉末は、表面に強固な酸化ニッケル及び水酸化ニッケル被膜を有しているので、焼結開始温度が従来のニッケル粉末に比べてより高く、積層セラミックコンデンサを製造する際に用いる誘電体の焼結開始温度により近い。したがって、本発明のニッケル粉末では、加熱時の酸化挙動また焼結挙動が従来のニッケル粉末に比べ優れているので、デラミネーションを有効に防止することができる。
Since the nickel powder of the present invention has a strong nickel oxide and nickel hydroxide coating on the surface, the sintering start temperature is higher than that of the conventional nickel powder, and the dielectric powder used when manufacturing the multilayer ceramic capacitor is used. It is closer to the sintering start temperature of the body. Therefore, the nickel powder of the present invention is superior in oxidation behavior and sintering behavior during heating as compared with conventional nickel powder, so that delamination can be effectively prevented.
また、本発明のニッケル粉末は、純水等の溶媒での分散性が良い。
Further, the nickel powder of the present invention has good dispersibility in a solvent such as pure water.
本発明のＮｉ２ｐ３／２スペクトル全体とは、Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、金属ニッケルに帰属されるピーク、ニッケルと酸素の結合状態に帰属されるピークおよびニッケルと水酸基の結合状態に帰属されるピークに起因するスペクトルである。各スペクトルの面積比は、得られたＮｉ２ｐ３／２スペクトルをピーク分離して、各スペクトルの面積を算出し、その総和に対する各スペクトルの面積割合を求める。
The entire Ni2p 3/2 spectrum of the present invention is the peak attributed to metallic nickel, the combined state of nickel and oxygen in the analysis of the chemical bonding state of nickel on the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS). It is the spectrum resulting from the peak attributed to and the peak attributed to the bonding state of nickel and a hydroxyl group. The area ratio of each spectrum is obtained by peak-separating the obtained Ni2p 3/2 spectrum, calculating the area of each spectrum, and determining the area ratio of each spectrum relative to the sum.
本発明の被膜の厚さは、透過型電子顕微鏡にて、ニッケル粉末試料の格子像を観察し、ニッケル粉末表面の被膜厚さを６点測定して、その平均を求めたものである。
The thickness of the coating of the present invention is obtained by observing a lattice image of a nickel powder sample with a transmission electron microscope, measuring the film thickness of the nickel powder surface at six points, and calculating the average.
より好ましくは、Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、ニッケルと酸素の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が６０．０～７５．０％、金属ニッケルのピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が７．０～１３．０％、ニッケルと水酸基の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が１２．０～３３．０％であって、酸化ニッケル及び水酸化ニッケルの被膜の厚さの平均が３．５～４．５ｎｍである。
More preferably, in the analysis of the chemical bonding state of nickel on the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS), the area ratio of the peak attributed to the bonding state of nickel and oxygen to the entire Ni2p 3/2 spectrum is 60. 0.0 to 75.0%, the area ratio of the peak of nickel metal to the entire Ni2p 3/2 spectrum is 7.0 to 13.0%, and the entire Ni2p 3/2 spectrum of the peak attributed to the bonding state between nickel and a hydroxyl group The area ratio with respect to the thickness is 12.0 to 33.0%, and the average thickness of the nickel oxide and nickel hydroxide coatings is 3.5 to 4.5 nm.
［ニッケル粉末の製造方法］
本発明のニッケル粉末は、例えば、気相法や液相法など既知の方法で製造することができる。特に塩化ニッケルガスと還元性ガスとを接触させることによりニッケル粉末を生成する気相還元法、あるいは熱分解性のニッケル化合物を噴霧して熱分解する噴霧熱分解法は、生成する金属微粉末の粒径を容易に制御することができ、さらに球状の粒子を効率よく製造することができるという点において好ましい。特に、塩化ニッケルガスを還元性ガスと接触させることによる気相還元法は、生成するニッケル粉末の粒径を精密に制御でき、さらに粗大粒子の発生を防止できる点から好ましい。 [Production method of nickel powder]
The nickel powder of the present invention can be produced by a known method such as a gas phase method or a liquid phase method. In particular, the vapor phase reduction method in which nickel powder is produced by bringing nickel chloride gas into contact with a reducing gas, or the spray pyrolysis method in which a thermally decomposable nickel compound is sprayed to thermally decompose is used to produce fine metal powder. It is preferable in that the particle size can be easily controlled, and spherical particles can be efficiently produced. In particular, the vapor phase reduction method in which nickel chloride gas is brought into contact with a reducing gas is preferable from the viewpoint that the particle diameter of the produced nickel powder can be precisely controlled and the generation of coarse particles can be prevented.
本発明のニッケル粉末は、例えば、気相法や液相法など既知の方法で製造することができる。特に塩化ニッケルガスと還元性ガスとを接触させることによりニッケル粉末を生成する気相還元法、あるいは熱分解性のニッケル化合物を噴霧して熱分解する噴霧熱分解法は、生成する金属微粉末の粒径を容易に制御することができ、さらに球状の粒子を効率よく製造することができるという点において好ましい。特に、塩化ニッケルガスを還元性ガスと接触させることによる気相還元法は、生成するニッケル粉末の粒径を精密に制御でき、さらに粗大粒子の発生を防止できる点から好ましい。 [Production method of nickel powder]
The nickel powder of the present invention can be produced by a known method such as a gas phase method or a liquid phase method. In particular, the vapor phase reduction method in which nickel powder is produced by bringing nickel chloride gas into contact with a reducing gas, or the spray pyrolysis method in which a thermally decomposable nickel compound is sprayed to thermally decompose is used to produce fine metal powder. It is preferable in that the particle size can be easily controlled, and spherical particles can be efficiently produced. In particular, the vapor phase reduction method in which nickel chloride gas is brought into contact with a reducing gas is preferable from the viewpoint that the particle diameter of the produced nickel powder can be precisely controlled and the generation of coarse particles can be prevented.
気相還元法においては、気化させた塩化ニッケルのガスと水素等の還元性ガスとを反応させる。この場合に固体の塩化ニッケルを加熱し蒸発させて塩化ニッケルガスを生成してもよい。しかしながら、塩化ニッケルの酸化または吸湿防止、およびエネルギー効率を考慮すると、金属ニッケルに塩素ガスを接触させて塩化ニッケルガスを連続的に発生させ、この塩化ニッケルガスを還元工程に直接供給し、次いで還元性ガスと接触させ塩化ニッケルガスを連続的に還元してニッケル微粉末を製造する方法が有利である。気相還元法は、個数平均粒子径Ｄと結晶子径ｄの比（ｄ／Ｄ）が０．４０以上のニッケル粉末を高い収率で得ることができる。
In the vapor phase reduction method, vaporized nickel chloride gas is reacted with a reducing gas such as hydrogen. In this case, nickel chloride gas may be generated by heating and evaporating solid nickel chloride. However, in consideration of nickel chloride oxidation or moisture absorption prevention and energy efficiency, the metal chloride is brought into contact with chlorine gas to continuously generate nickel chloride gas, and this nickel chloride gas is directly supplied to the reduction process and then reduced. It is advantageous to produce nickel fine powder by contacting nickel chloride gas and continuously reducing nickel chloride gas. The vapor phase reduction method can obtain nickel powder having a ratio of the number average particle diameter D to the crystallite diameter d (d / D) of 0.40 or more with a high yield.
ニッケルを主成分とする合金粉末の製造方法に使用される場合の塩化ニッケルガス以外の金属塩化物ガスは、三塩化珪素（ＩＩＩ）ガス、四塩化珪素（ＩＶ）ガス、モノシランガス、塩化銅（Ｉ）ガス、塩化銅（ＩＩ）ガス、塩化銀ガス、塩化モリブデンガス（ＩＩＩ）ガス、塩化モリブデン（Ｖ）ガス、塩化鉄（ＩＩ）ガス、塩化鉄（ＩＩＩ）ガス、塩化クロム（ＩＩＩ）ガス、塩化クロム（ＶＩ）ガス、塩化タングステン（ＩＩ）ガス、塩化タングステン（ＩＩＩ）ガス、塩化タングステン（ＩＶ）ガス、塩化タングステン（Ｖ）ガス、塩化タングステン（ＶＩ）ガス、塩化タンタル（ＩＩＩ）ガス、塩化タンタル（Ｖ）ガス、塩化コバルトガス、塩化レニウム（ＩＩＩ）ガス、塩化レニウム（ＩＶ）ガス、塩化レニウム（Ｖ）ガス、ジボランガス、ホスフィンガス等及びこれらの混合ガスが挙げられる。
Metal chloride gases other than nickel chloride gas when used in a method for producing an alloy powder containing nickel as a main component are silicon trichloride (III) gas, silicon tetrachloride (IV) gas, monosilane gas, copper chloride (I ) Gas, copper chloride (II) gas, silver chloride gas, molybdenum chloride gas (III) gas, molybdenum chloride (V) gas, iron chloride (II) gas, iron chloride (III) gas, chromium chloride (III) gas, Chromium chloride (VI) gas, tungsten chloride (II) gas, tungsten chloride (III) gas, tungsten chloride (IV) gas, tungsten chloride (V) gas, tungsten chloride (VI) gas, tantalum chloride (III) gas, chloride Tantalum (V) gas, cobalt chloride gas, rhenium chloride (III) gas, rhenium chloride (IV) gas, rhenium chloride (V) gas, Borangasu include phosphine gas or the like, and a mixed gas thereof.
また還元性ガスには、水素ガス、硫化水素ガス、アンモニアガス、一酸化炭素ガス、メタンガスおよびこれらの混合ガスが挙げられる。特に好ましくは、水素ガス、硫化水素ガス、アンモニアガス、およびこれらの混合ガスである。
Further, examples of the reducing gas include hydrogen gas, hydrogen sulfide gas, ammonia gas, carbon monoxide gas, methane gas, and a mixed gas thereof. Particularly preferred are hydrogen gas, hydrogen sulfide gas, ammonia gas, and mixed gas thereof.
気相還元反応によるニッケル粉末の製造過程では、塩化ニッケルガスと還元性ガスとが接触した瞬間にニッケル原子が生成し、ニッケル原子どうしが衝突・凝集することによってニッケル粒子が生成し、成長する。そして、還元工程での塩化ニッケルガスの分圧や温度等の条件によって、生成するニッケル粉末の粒径が決まる。上記のようなニッケル粉末の製造方法によれば、塩素ガスの供給量に応じた量の塩化ニッケルガスが発生するから、塩素ガスの供給量を制御することで還元工程へ供給する塩化ニッケルガスの量を調整することができ、これによって生成するニッケル粉末の粒径を制御することができる。
In the production process of nickel powder by vapor phase reduction reaction, nickel atoms are generated at the moment when the nickel chloride gas and the reducing gas come into contact with each other, and nickel particles collide and agglomerate to generate and grow nickel particles. The particle diameter of the nickel powder to be generated is determined by conditions such as the partial pressure and temperature of the nickel chloride gas in the reduction step. According to the nickel powder manufacturing method as described above, an amount of nickel chloride gas corresponding to the supply amount of chlorine gas is generated. Therefore, the amount of nickel chloride gas supplied to the reduction process is controlled by controlling the supply amount of chlorine gas. The amount can be adjusted, thereby controlling the particle size of the nickel powder produced.
さらに、塩化ニッケルガスは、塩素ガスと金属との反応で発生するから、固体塩化ニッケルの加熱蒸発により塩化ニッケルガスを発生させる方法とは異なり、キャリアガスの使用を少なくすることができるばかりでなく、製造条件によっては使用しないことも可能である。したがって、気相還元反応の方が、キャリアガスの使用量低減とそれに伴う加熱エネルギーの低減により、製造コストの削減を図ることができる。
Furthermore, since nickel chloride gas is generated by the reaction of chlorine gas and metal, unlike the method of generating nickel chloride gas by heating evaporation of solid nickel chloride, not only can the use of carrier gas be reduced. Depending on the manufacturing conditions, it is possible not to use them. Therefore, in the gas phase reduction reaction, the production cost can be reduced by reducing the amount of carrier gas used and the accompanying reduction in heating energy.
また、塩化工程で発生した塩化ニッケルガスに不活性ガスを混合することにより、還元工程における塩化ニッケルガスの分圧を制御することができる。このように、塩素ガスの供給量もしくは還元工程に供給する塩化ニッケルガスの分圧を制御することにより、ニッケル粉末の粒径を制御することができ、粒径のばらつきを抑えることができるとともに、粒径を任意に設定することができる。
Moreover, the partial pressure of nickel chloride gas in the reduction process can be controlled by mixing an inert gas with the nickel chloride gas generated in the chlorination process. Thus, by controlling the supply amount of chlorine gas or the partial pressure of nickel chloride gas supplied to the reduction process, the particle size of nickel powder can be controlled, and variation in particle size can be suppressed, The particle size can be arbitrarily set.
例えば、出発原料である塩化ニッケルは、純度は９９．５％以上の粒状、塊状、板状等の金属ニッケルを、まず塩素ガスと反応させて塩化ニッケルガスを生成させる。その際の温度は、反応を十分進めるために８００℃以上とし、かつニッケルの融点である１４５３℃以下とする。反応速度と塩化炉の耐久性を考慮すると、実用的には９００℃～１１００℃の範囲が好ましい。
For example, nickel chloride as a starting material is made by reacting metallic nickel having a purity of 99.5% or more in the form of particles, lumps, plates, etc. with chlorine gas to generate nickel chloride gas. In this case, the temperature is set to 800 ° C. or higher for sufficient progress of the reaction, and 1453 ° C. or lower, which is the melting point of nickel. Considering the reaction rate and the durability of the chlorination furnace, the range of 900 ° C. to 1100 ° C. is preferable for practical use.
次いで、この塩化ニッケルガスを還元工程に直接供給し、水素ガス等の還元性ガスと接触反応させる。その際に、塩化ニッケルガスを適宜アルゴン、窒素等の不活性ガスで希釈して塩化ニッケルガスの分圧を制御することができる。塩化ニッケルガスの分圧を制御することにより、還元部で生成する金属粉末の粒度分布等の品質を制御することができる。これにより生成する金属粉末の品質を任意に設定できるとともに、品質を安定させることができる。還元反応の温度は反応完結に十分な温度以上であればよく、ニッケルの融点以下が好ましく、経済性を考慮すると９００℃～１１００℃が実用的である。
Next, this nickel chloride gas is directly supplied to the reduction process and brought into contact with a reducing gas such as hydrogen gas. At that time, the partial pressure of the nickel chloride gas can be controlled by appropriately diluting the nickel chloride gas with an inert gas such as argon or nitrogen. By controlling the partial pressure of the nickel chloride gas, the quality such as the particle size distribution of the metal powder produced in the reducing part can be controlled. Thereby, while being able to set arbitrarily the quality of the metal powder to produce | generate, quality can be stabilized. The temperature of the reduction reaction may be at least the temperature sufficient for completion of the reaction, preferably below the melting point of nickel, and practically 900 ° C. to 1100 ° C. in view of economy.
このように還元反応を行なったニッケル粉末を生成したら、生成したニッケル粉末を冷却する。冷却の際、生成したニッケルの一次粒子同士の凝集による二次粒子の生成を防止して所望の粒径のニッケル粉末を得るために、窒素ガス等の不活性ガスを吹き込むことにより、還元反応を終えた１０００℃付近のガス流を４００～８００℃程度までに急速冷却することが望ましい。その後、生成したニッケル粉末を、例えばバグフィルター等により分離、回収する。
When the nickel powder subjected to the reduction reaction is generated in this way, the generated nickel powder is cooled. During cooling, in order to prevent the formation of secondary particles due to aggregation of primary particles of the generated nickel and obtain nickel powder with a desired particle size, a reduction reaction is performed by blowing an inert gas such as nitrogen gas. It is desirable to rapidly cool the finished gas flow around 1000 ° C. to about 400 to 800 ° C. Thereafter, the produced nickel powder is separated and collected by, for example, a bag filter or the like.
噴霧熱分解法によるニッケル粉末の製造方法では、熱分解性のニッケル化合物を原料とする。具体的には、硝酸塩、硫酸塩、オキシ硝酸塩、オキシ硫酸塩、塩化物、アンモニウム錯体、リン酸塩、カルボン酸塩、アルコキシ化合物などの１種または２種以上が含まれる。このニッケル化合物を含む溶液を噴霧して、微細な液滴を作る。このときの溶媒としては、水、アルコール、アセトン、エーテル等が用いられる。また、噴霧の方法は、超音波または二重ジェットノズル等の噴霧方法により行う。このようにして微細な液滴とし、高温で加熱して金属化合物を熱分解し、ニッケル粉末を生成する。このときの加熱温度は、使用される特定のニッケル化合物が熱分解する温度以上であり、好ましくは金属の融点付近である。
In the method for producing nickel powder by the spray pyrolysis method, a heat decomposable nickel compound is used as a raw material. Specifically, one or more of nitrate, sulfate, oxynitrate, oxysulfate, chloride, ammonium complex, phosphate, carboxylate, alkoxy compound and the like are included. The solution containing the nickel compound is sprayed to form fine droplets. As the solvent at this time, water, alcohol, acetone, ether or the like is used. The spraying method is performed by a spraying method such as ultrasonic or double jet nozzle. In this way, fine droplets are formed and heated at a high temperature to thermally decompose the metal compound to produce nickel powder. The heating temperature at this time is equal to or higher than the temperature at which the specific nickel compound used is thermally decomposed, and is preferably near the melting point of the metal.
液相法によるニッケル粉末の製造方法では、硫酸ニッケル、塩化ニッケルあるいはニッケル錯体を含むニッケル水溶液を、水酸化ナトリウムなどのアルカリ金属水酸化物中に添加するなどして接触させてニッケル水酸化物を生成し、次いでヒドラジンなどの還元剤でニッケル水酸化物を還元し金属ニッケル粉末を得る。このようにして生成した金属ニッケル粉末は、均一な粒子を得るために必要に応じて解砕処理を行う。
In the method for producing nickel powder by the liquid phase method, nickel hydroxide containing nickel sulfate, nickel chloride or a nickel complex is brought into contact by adding it to an alkali metal hydroxide such as sodium hydroxide. Then, the nickel hydroxide is reduced with a reducing agent such as hydrazine to obtain metallic nickel powder. The nickel metal powder thus produced is crushed as necessary to obtain uniform particles.
以上の方法で得られたニッケル粉末は、残留する原料を除去するため、液相中に分散させ、洗浄を行うことが好ましい。例えば、以上の方法で得られたニッケル粉末を、ｐＨや温度を制御した特定の条件で炭酸水溶液中に懸濁させて処理を行う。炭酸水溶液で処理することにより、ニッケル粉末の表面に付着している塩素などの不純物が十分に除去されるとともに、ニッケル粉末の表面に存在する酸化ニッケルなどの酸化物、水酸化ニッケルなどの水酸化物や粒子同士の摩擦などにより表面から離間して形成された微粒子が除去され、水中の溶存酸素により酸化ニッケルと水酸化ニッケルからなる薄く均一な被膜を再形成することができる。炭酸水溶液での処理方法としては、ニッケル粉末と炭酸水溶液を混合する方法、あるいはニッケル粉末を純水で一旦洗浄した後の水スラリー中に炭酸ガスを吹き込むか、あるいはニッケル粉末を純水で一旦洗浄した後の水スラリー中に炭酸水溶液を添加して処理することもできる。
The nickel powder obtained by the above method is preferably dispersed and washed in the liquid phase in order to remove the remaining raw material. For example, the nickel powder obtained by the above method is suspended in a carbonic acid aqueous solution under specific conditions with controlled pH and temperature. By treating with an aqueous carbonate solution, impurities such as chlorine adhering to the surface of the nickel powder are sufficiently removed, and oxides such as nickel oxide and nickel hydroxide such as nickel hydroxide existing on the surface of the nickel powder are removed. Fine particles formed away from the surface due to friction between objects and particles are removed, and a thin and uniform film made of nickel oxide and nickel hydroxide can be re-formed by dissolved oxygen in water. As a treatment method with a carbonic acid aqueous solution, a method in which nickel powder and a carbonic acid aqueous solution are mixed, or carbon dioxide gas is blown into a water slurry after the nickel powder is once washed with pure water, or the nickel powder is once washed with pure water. The aqueous slurry can be treated by adding an aqueous carbonate solution.
本発明のニッケル粉末に硫黄を含有させる方法は、特に限定されるものではなく、例えば以下の方法を採用することができる。
（１）上記還元反応中に硫黄含有ガスを添加する方法
（２）ニッケル粉末を硫黄含有ガスと接触処理する方法
（３）ニッケル粉末と固体の硫黄含有化合物を乾式で混合する方法
（４）ニッケル粉末を液相中に分散させたスラリー中に硫黄含有化合物溶液を添加する方法
（５）ニッケル粉末を液相中に分散させたスラリー中に硫黄含有ガスをバブリングする方法 The method for incorporating sulfur into the nickel powder of the present invention is not particularly limited, and for example, the following method can be employed.
(1) Method of adding sulfur-containing gas during the reduction reaction (2) Method of contacting nickel powder with sulfur-containing gas (3) Method of mixing nickel powder and solid sulfur-containing compound in a dry process (4) Nickel Method of adding sulfur-containing compound solution in slurry in which powder is dispersed in liquid phase (5) Method of bubbling sulfur-containing gas in slurry in which nickel powder is dispersed in liquid phase
（１）上記還元反応中に硫黄含有ガスを添加する方法
（２）ニッケル粉末を硫黄含有ガスと接触処理する方法
（３）ニッケル粉末と固体の硫黄含有化合物を乾式で混合する方法
（４）ニッケル粉末を液相中に分散させたスラリー中に硫黄含有化合物溶液を添加する方法
（５）ニッケル粉末を液相中に分散させたスラリー中に硫黄含有ガスをバブリングする方法 The method for incorporating sulfur into the nickel powder of the present invention is not particularly limited, and for example, the following method can be employed.
(1) Method of adding sulfur-containing gas during the reduction reaction (2) Method of contacting nickel powder with sulfur-containing gas (3) Method of mixing nickel powder and solid sulfur-containing compound in a dry process (4) Nickel Method of adding sulfur-containing compound solution in slurry in which powder is dispersed in liquid phase (5) Method of bubbling sulfur-containing gas in slurry in which nickel powder is dispersed in liquid phase
特に、硫黄含有量を精密に制御できる点や硫黄を均一に添加できる観点から（１）および（４）の方法が好ましい。（１）、（２）、（５）の方法において使用される硫黄含有ガスは、特に限定されるものではなく、硫黄蒸気、二酸化硫黄ガス、硫化水素ガス等、還元工程の温度下において気体であるガスをそのまま、あるいは希釈して使用することができる。この中でも常温で気体であり流量の制御が容易な点や不純物の混入のおそれの低い点から二酸化硫黄ガス、および硫化水素ガスが有利である。
In particular, the methods (1) and (4) are preferable from the viewpoint that the sulfur content can be precisely controlled and sulfur can be added uniformly. The sulfur-containing gas used in the methods (1), (2), and (5) is not particularly limited, and is a gas at the temperature of the reduction process, such as sulfur vapor, sulfur dioxide gas, and hydrogen sulfide gas. A certain gas can be used as it is or after being diluted. Of these, sulfur dioxide gas and hydrogen sulfide gas are advantageous because they are gases at room temperature and the flow rate can be easily controlled and impurities are less likely to be mixed.
前述の洗浄工程および硫黄添加工程の後、ニッケル粉末スラリーを乾燥する。乾燥方法は特に限定されるものではなく、既知の方法を使用することができる。具体的には高温のガスと接触させ乾燥する気流乾燥、加熱乾燥、真空乾燥などが挙げられる。このうち、気流乾燥は粒子同士の衝突による硫黄含有層の破壊がないため好ましい。
The nickel powder slurry is dried after the aforementioned washing step and sulfur addition step. The drying method is not particularly limited, and a known method can be used. Specific examples include air-flow drying, drying by heating, and vacuum drying that are brought into contact with a high-temperature gas to dry. Among these, air drying is preferable because there is no destruction of the sulfur-containing layer due to collision between particles.
上記のようにして得られたニッケル粉末に対して、特定の条件にて酸化処理を施す。酸化処理の具体的な方法としては、酸化性ガス（例えば、酸素ガスやオゾンガス）を含む雰囲気下（例えば、空気中、酸素ガスの雰囲気中、酸素ガスを含む不活性ガス（窒素、アルゴンなど）の雰囲気下など）において、加熱処理を行う方法が挙げられる。このときの最適な加熱処理温度は、粒径によって異なるが、積層セラミックコンデンサの製造工程で用いられる平均粒径２５０ｎｍ以下では、１４０～１８０℃が好ましく、特に平均粒径１４０～２５０ｎｍでは、空気中において、１６０～１８０℃で１分～４時間保持することが好ましい。Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、ニッケルと酸素の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５５．０～８０．０％、金属ニッケルのピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～１５．０％となるように、上記熱処理条件（温度、時間）を調整し、適宜行われる。このように、ニッケル粉末を酸化処理することにより、さらに強固な酸化ニッケルの被膜が形成される。
The nickel powder obtained as described above is subjected to an oxidation treatment under specific conditions. As a specific method of the oxidation treatment, an atmosphere containing an oxidizing gas (for example, oxygen gas or ozone gas) (for example, in an air or oxygen gas atmosphere, an inert gas containing oxygen gas (nitrogen, argon, etc.)) And the like, and a method of performing a heat treatment. The optimum heat treatment temperature at this time varies depending on the particle diameter, but is preferably 140 to 180 ° C. when the average particle diameter is 250 nm or less used in the production process of the multilayer ceramic capacitor, and particularly in the air when the average particle diameter is 140 to 250 nm. In this case, the temperature is preferably maintained at 160 to 180 ° C for 1 minute to 4 hours. In analysis of the chemical bonding state of nickel on the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS), the area ratio of the peak attributed to the bonding state of nickel and oxygen to the entire Ni2p 3/2 spectrum is 55.0 to 80 The heat treatment conditions (temperature, time) are adjusted as appropriate so that the area ratio of the nickel nickel peak to the entire Ni2p 3/2 spectrum is 5.0 to 15.0%. In this way, a stronger nickel oxide film is formed by oxidizing nickel powder.
本発明のニッケル粉末は、ペースト原料として用いることができる。より好ましくは、上記ニッケル粉末と、有機溶媒を含むニッケルペーストである。また、必要に応じて、エチルセルロース等の有機バインダー、分散剤、及び塗布しようとするセラミックスの未焼成粉を含んでいても良い。
The nickel powder of the present invention can be used as a paste raw material. More preferably, it is a nickel paste containing the nickel powder and an organic solvent. Further, if necessary, an organic binder such as ethyl cellulose, a dispersant, and an unfired powder of the ceramic to be coated may be included.
このニッケルペーストは、上記ニッケル粉末と、例えば、ターピネオール等の有機溶媒、必要に応じて、エチルセルロース等の有機バインダー、分散剤、及び塗布しようとするセラミックスの未焼成粉を加え、３本ロールで混練するといった公知の方法で、容易に、好ましい特性のニッケルペーストを製造することができる。有機溶媒としては、アルコール、アセトン、プロパノール、酢酸エチル、酢酸ブチル、エーテル、石油エーテル、ミネラルスピリット、その他のパラフィン系炭化水素溶剤、あるいは、ブチルカルビトール、ターピネオール、ジヒドロターピネオール、ブチルカルビトールアセテート、ジヒドロターピネオールアセテート、ジヒドロカルビルアセテート、カルビルアセテート、ターピニルアセテート、リナリールアセテート等のアセテート系や、ジヒドロターピニルプロピオネート、ジヒドロカルビルプロピオネート、イソボニルプロピオネートなどのプロピオネート系溶剤、エチルセロソルブやブチルセロソルブなどのセロソルブ類、芳香族類、ジエチルフタレートなどが挙げられる。
This nickel paste is added to the above nickel powder, for example, an organic solvent such as terpineol, an organic binder such as ethyl cellulose, a dispersant, and an unfired ceramic powder to be applied, if necessary, and kneaded with three rolls. Thus, a nickel paste having desirable characteristics can be easily produced by a known method. Organic solvents include alcohol, acetone, propanol, ethyl acetate, butyl acetate, ether, petroleum ether, mineral spirit, other paraffinic hydrocarbon solvents, or butyl carbitol, terpineol, dihydroterpineol, butyl carbitol acetate, dihydro Propionate solvents such as terpineol acetate, dihydrocarbyl acetate, carbyl acetate, terpinyl acetate, linalyl acetate, etc., dihydroterpinyl propionate, dihydrocarbyl propionate, isobornyl propionate, Examples include cellosolves such as ethyl cellosolve and butyl cellosolve, aromatics, and diethyl phthalate.
また、有機バインダーとしては、樹脂結合剤が好ましく、例えばエチルセルロース、ポリビニルアセタール、アクリル樹脂、アルキッド樹脂等が挙げられる。
The organic binder is preferably a resin binder, and examples thereof include ethyl cellulose, polyvinyl acetal, acrylic resin, alkyd resin, and the like.
分散剤としては、周知の適宜のものを用い得るが、例えば、ビニル系ポリマー、ポリカルボン酸アミン塩、ポリカルボン酸系等を用いることができる。
As the dispersant, a known appropriate one can be used, and for example, a vinyl polymer, a polycarboxylic acid amine salt, a polycarboxylic acid type, or the like can be used.
上記のようにして得られた本発明のニッケル粉末は、その表面に、ある程度の厚みと緻密度をもった酸化ニッケル及び水酸化ニッケルを含む被膜を有しているので、積層セラミックコンデンサの製造工程において優れた焼結挙動を示し、デラミネーションの発生を防止することができる。より具体的には、加熱処理した際、酸化還元反応による体積変化あるいは重量変化が少ないことは勿論のこと、焼結開始温度が従来のニッケル粉末に比べてより高いため、積層セラミックコンデンサを製造する際に用いる誘電体の焼結開始温度により近くなり、その結果、デラミネーションの発生を有効に防止することができる。
Since the nickel powder of the present invention obtained as described above has a coating film containing nickel oxide and nickel hydroxide having a certain thickness and density on the surface, the production process of the multilayer ceramic capacitor Exhibits excellent sintering behavior and prevents the occurrence of delamination. More specifically, when the heat treatment is performed, the volume change or weight change due to the oxidation-reduction reaction is small, and the sintering start temperature is higher than that of the conventional nickel powder, so that a multilayer ceramic capacitor is manufactured. It becomes closer to the sintering start temperature of the dielectric used at the time, and as a result, generation of delamination can be effectively prevented.
次に、実施例および比較例を挙げて本発明をさらに具体的に説明するが、これは単に例示であって、本発明を制限するものではない。
Next, the present invention will be described more specifically with reference to examples and comparative examples. However, this is merely an example and does not limit the present invention.
［実施例１］
塩化ニッケルと水素を反応させる気相反応法の後、純水中および炭酸水溶液中で洗浄を行い、ニッケル粉末を液相中に分散させたスラリー中に硫黄含有化合物溶液を添加し、乾燥させて、ニッケル粉末を用意した。得られたニッケル粉末の個数平均粒径は１９１ｎｍ、平均アスペクト比は１．２、平均円形度係数は０．６８の球状ニッケル粉であることが確認された。また、比表面積は４．０ｍ２／ｇであり、比表面積径は１６８ｎｍであった。さらに、個数平均粒径ｄと比表面積径の比ｄ／Ｄは０．８８であった。 [Example 1]
After the gas phase reaction method in which nickel chloride and hydrogen are reacted, washing is performed in pure water and an aqueous carbonate solution, and a sulfur-containing compound solution is added to a slurry in which nickel powder is dispersed in a liquid phase, followed by drying. Nickel powder was prepared. It was confirmed that the obtained nickel powder was a spherical nickel powder having a number average particle diameter of 191 nm, an average aspect ratio of 1.2, and an average circularity coefficient of 0.68. Moreover, the specific surface area was 4.0 m < 2 > / g and the specific surface area diameter was 168 nm. Further, the ratio d / D of the number average particle diameter d and the specific surface area diameter was 0.88.
塩化ニッケルと水素を反応させる気相反応法の後、純水中および炭酸水溶液中で洗浄を行い、ニッケル粉末を液相中に分散させたスラリー中に硫黄含有化合物溶液を添加し、乾燥させて、ニッケル粉末を用意した。得られたニッケル粉末の個数平均粒径は１９１ｎｍ、平均アスペクト比は１．２、平均円形度係数は０．６８の球状ニッケル粉であることが確認された。また、比表面積は４．０ｍ２／ｇであり、比表面積径は１６８ｎｍであった。さらに、個数平均粒径ｄと比表面積径の比ｄ／Ｄは０．８８であった。 [Example 1]
After the gas phase reaction method in which nickel chloride and hydrogen are reacted, washing is performed in pure water and an aqueous carbonate solution, and a sulfur-containing compound solution is added to a slurry in which nickel powder is dispersed in a liquid phase, followed by drying. Nickel powder was prepared. It was confirmed that the obtained nickel powder was a spherical nickel powder having a number average particle diameter of 191 nm, an average aspect ratio of 1.2, and an average circularity coefficient of 0.68. Moreover, the specific surface area was 4.0 m < 2 > / g and the specific surface area diameter was 168 nm. Further, the ratio d / D of the number average particle diameter d and the specific surface area diameter was 0.88.
上記ニッケル粉末を酸化性雰囲気下において１７５℃で４時間の酸化処理を行い、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。
The nickel powder was oxidized at 175 ° C. for 4 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
また、実施例１のニッケル粉末は、赤外線吸収スペクトル分析を行うと、金属ニッケルに化学的に結合するＯＨ基に起因する波数が３６００～３７００ｃｍ－１の吸収ピークが観察された。
Further, when the nickel powder of Example 1 was subjected to infrared absorption spectrum analysis, an absorption peak having a wave number of 3600 to 3700 cm −1 due to the OH group chemically bonded to metallic nickel was observed.
［比較例１］
酸化性雰囲気下において１５５℃で２時間の酸化処理を行った以外は実施例１と同様に試料を作製し、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。 [Comparative Example 1]
A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was performed at 155 ° C. for 2 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
酸化性雰囲気下において１５５℃で２時間の酸化処理を行った以外は実施例１と同様に試料を作製し、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。 [Comparative Example 1]
A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was performed at 155 ° C. for 2 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
［比較例２］
酸化処理を行わなかった以外は実施例１と同様に試料を作製し、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。 [Comparative Example 2]
A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was not performed to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
酸化処理を行わなかった以外は実施例１と同様に試料を作製し、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。 [Comparative Example 2]
A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was not performed to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
［比較例３］
酸化性雰囲気下において２３０℃で２時間の酸化処理を行った以外は実施例１と同様に試料を作製し、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。 [Comparative Example 3]
A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was performed at 230 ° C. for 2 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
酸化性雰囲気下において２３０℃で２時間の酸化処理を行った以外は実施例１と同様に試料を作製し、ニッケル粉末を得た。酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）測定、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度、比表面積径、個数平均粒径と比表面積径の比の測定結果を表１、焼結挙動の結果を図１に示した。 [Comparative Example 3]
A sample was prepared in the same manner as in Example 1 except that the oxidation treatment was performed at 230 ° C. for 2 hours in an oxidizing atmosphere to obtain nickel powder. Oxygen content, average particle size, X-ray photoelectron spectroscopy (XPS) measurement, dispersibility evaluation, nickel oxide and nickel hydroxide coating thickness, 2% heat shrinkage temperature, specific surface area diameter, number average particle size and ratio The measurement results of the ratio of the surface area diameters are shown in Table 1, and the results of the sintering behavior are shown in FIG.
測定
上記各実施例および比較例のニッケル粉末の酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）による金属ニッケルと表面酸化物、表面水酸化物の面積の割合、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度の測定方法を下記に示す。
１）酸素含有率
試料のニッケル粉末をニッケル製のカプセルに充填し、これを黒鉛るつぼに入れ、アルゴン雰囲気中で５００℃に加熱し、このとき発生した一酸化炭素をフーリエ変換型赤外分光光度計により定量し、ニッケル粉末中の酸素含有率を求めた。
２）平均粒径
電子顕微鏡により試料の写真を撮影し、その写真から画像解析ソフトを使用して、粉末９００個の粒径を測定してその個数平均粒径を算出した。このとき、粒径は粒子を包み込む最小円の直径である。
３）Ｘ線光電子分光分析（ＸＰＳ）測定
Ｘ線光電子分光分析装置（サーモフィッシャーサイエンティフィック株式会社製、Ｋ－ＡＬＰＨＡ＋）を用い、粉末表面のＮｉ２ｐ３／２スペクトルを測定し、分析装置に付属する解析ソフト「Ａｖａｎｔａｇｅ Ｖｅｒ．５．９５１」を用い、そのスペクトルをピーク分離して、Ｎｉ２ｐ３／２スペクトル全体に対する金属ニッケルのピーク、ニッケルと酸素の結合状態に帰属されるピーク、ニッケルと水酸化物の結合状態に帰属されるピークの面積比を算出した。
４）分散性評価
ニッケル粉末０．０５ｇを純水１００ｇに入れ、超音波分散機（株式会社ソニックテクノロジー、ＧＳＤ６００ＡＴ）にて１分間、分散を行った。試料の分散処理後、３μｍのメンブレンフィルターを用い、減圧濾過を行い、メンブレンフィルターを全量スラリーが通過するのに擁した時間が３０秒以内であれば良（○）、３０秒より時間がかかった場合は不良（×）とした。
５）酸化ニッケル及び水酸化ニッケルの被膜の厚さ
ニッケル粉末を、コロジオン膜を張った銅製シートメッシュ上に直接振りかけ、その後カーボンを蒸着させ測定試料を作成した。次いで、透過型電子顕微鏡（日本電子株式会社製、ＪＥＭ－２１００Ｆ）を用い、加速電圧２００ｋＶの条件で測定試料の格子像を観察し、ニッケル粉末表面の酸化ニッケル及び水酸化ニッケルの被膜厚さを６点測定し、その平均を算出した。
６）２％熱収縮温度及び焼結挙動
ニッケル粉末１ｇ、しょうのう３重量％およびアセトン３重量％を混合し、内径５ｍｍ、長さ１０ｍｍの円柱状の金型に充填し、その後面圧１トンの荷重をかけ試験ピースを作成した。この試験ピースを、熱膨張収縮挙動（ｄｉｒａｔｏｍｅｔｒｙ）測定装置（ＴＭＡ、８３１０、株式会社リガク社製）を用い、窒素ガス（水素ガス２％含有）の雰囲気下で昇温速度１０℃／分の条件で測定を行った。また、熱膨張収縮挙動測定装置（ＴＭＡ）により測定される２％熱収縮の温度を２％熱収縮温度とした。
７）比表面積
ＢＥＴ比表面積測定装置（株式会社マウンテック社製）を用いて、窒素気流下で１６０℃、１時間の前処理後、比表面積測定を行い、その比表面積Ｓから、下記式（式１）を用いて比表面積径ｄを算出した。ここで、ρはニッケルの真密度である。さらに、個数平均粒子径Ｄと比表面積径ｄの比を算出した。 Measurement Oxygen content, average particle diameter, nickel metal and surface oxide by surface X-ray photoelectron spectroscopy (XPS), surface hydroxide ratio, dispersibility evaluation, oxidation The method for measuring the thickness of the nickel and nickel hydroxide coatings and the 2% heat shrinkage temperature is shown below.
1) Oxygen content The nickel powder of the sample is filled in a nickel capsule, put in a graphite crucible, heated to 500 ° C. in an argon atmosphere, and the carbon monoxide generated at this time is Fourier-transform infrared spectrophotometric. It quantified with the meter and calculated | required the oxygen content rate in nickel powder.
2) Average particle diameter A photograph of the sample was taken with an electron microscope, and using the image analysis software, the particle diameter of 900 powders was measured and the number average particle diameter was calculated. At this time, the particle diameter is the diameter of the smallest circle that encloses the particles.
3) X-ray photoelectron spectroscopic analysis (XPS) measurement Using an X-ray photoelectron spectroscopic analyzer (manufactured by Thermo Fisher Scientific Co., Ltd., K-ALPHA + ), the Ni2p 3/2 spectrum of the powder surface is measured and the analyzer is used. Using the attached analysis software “Avantage Ver. 5.951”, the spectrum is peak-separated, the peak of metallic nickel with respect to the entire Ni2p 3/2 spectrum, the peak attributed to the combined state of nickel and oxygen, nickel and water The area ratio of peaks attributed to the oxide bonding state was calculated.
4) Dispersibility evaluation 0.05 g of nickel powder was put in 100 g of pure water, and dispersed for 1 minute with an ultrasonic disperser (Sonic Technology Co., Ltd., GSD600AT). After sample dispersion treatment, vacuum filtration was performed using a 3 μm membrane filter. If the time taken for the slurry to pass through the membrane filter was within 30 seconds (◯), it took more than 30 seconds. In the case, it was regarded as defective (x).
5) Thickness of nickel oxide and nickel hydroxide film Nickel powder was directly sprinkled on a copper sheet mesh covered with a collodion film, and then carbon was deposited to prepare a measurement sample. Next, using a transmission electron microscope (manufactured by JEOL Ltd., JEM-2100F), the lattice image of the measurement sample was observed under the condition of an acceleration voltage of 200 kV, and the film thicknesses of nickel oxide and nickel hydroxide on the surface of the nickel powder were measured. Six points were measured and the average was calculated.
6) 2% heat shrinkage temperature and sintering behavior 1 g of nickel powder, 3% by weight of camphor and 3% by weight of acetone are mixed and filled into a cylindrical mold having an inner diameter of 5 mm and a length of 10 mm. A test piece was prepared by applying a load of tons. Using this test piece, a thermal dilatometry measuring device (TMA, 8310, manufactured by Rigaku Co., Ltd.), under a nitrogen gas atmosphere (containing 2% hydrogen gas), a temperature rising rate of 10 ° C./min. The measurement was performed. Further, the temperature of 2% heat shrinkage measured by a thermal expansion / shrinkage behavior measuring apparatus (TMA) was defined as 2% heat shrinkage temperature.
7) Specific surface area Using a BET specific surface area measuring device (manufactured by Mountec Co., Ltd.), a specific surface area is measured after pretreatment at 160 ° C. for 1 hour under a nitrogen stream. The specific surface area diameter d was calculated using 1). Here, ρ is the true density of nickel. Furthermore, the ratio of the number average particle diameter D and the specific surface area diameter d was calculated.
上記各実施例および比較例のニッケル粉末の酸素含有率、平均粒径、Ｘ線光電子分光分析（ＸＰＳ）による金属ニッケルと表面酸化物、表面水酸化物の面積の割合、分散性評価、酸化ニッケル及び水酸化ニッケルの被膜の厚さ、２％熱収縮温度の測定方法を下記に示す。
１）酸素含有率
試料のニッケル粉末をニッケル製のカプセルに充填し、これを黒鉛るつぼに入れ、アルゴン雰囲気中で５００℃に加熱し、このとき発生した一酸化炭素をフーリエ変換型赤外分光光度計により定量し、ニッケル粉末中の酸素含有率を求めた。
２）平均粒径
電子顕微鏡により試料の写真を撮影し、その写真から画像解析ソフトを使用して、粉末９００個の粒径を測定してその個数平均粒径を算出した。このとき、粒径は粒子を包み込む最小円の直径である。
３）Ｘ線光電子分光分析（ＸＰＳ）測定
Ｘ線光電子分光分析装置（サーモフィッシャーサイエンティフィック株式会社製、Ｋ－ＡＬＰＨＡ＋）を用い、粉末表面のＮｉ２ｐ３／２スペクトルを測定し、分析装置に付属する解析ソフト「Ａｖａｎｔａｇｅ Ｖｅｒ．５．９５１」を用い、そのスペクトルをピーク分離して、Ｎｉ２ｐ３／２スペクトル全体に対する金属ニッケルのピーク、ニッケルと酸素の結合状態に帰属されるピーク、ニッケルと水酸化物の結合状態に帰属されるピークの面積比を算出した。
４）分散性評価
ニッケル粉末０．０５ｇを純水１００ｇに入れ、超音波分散機（株式会社ソニックテクノロジー、ＧＳＤ６００ＡＴ）にて１分間、分散を行った。試料の分散処理後、３μｍのメンブレンフィルターを用い、減圧濾過を行い、メンブレンフィルターを全量スラリーが通過するのに擁した時間が３０秒以内であれば良（○）、３０秒より時間がかかった場合は不良（×）とした。
５）酸化ニッケル及び水酸化ニッケルの被膜の厚さ
ニッケル粉末を、コロジオン膜を張った銅製シートメッシュ上に直接振りかけ、その後カーボンを蒸着させ測定試料を作成した。次いで、透過型電子顕微鏡（日本電子株式会社製、ＪＥＭ－２１００Ｆ）を用い、加速電圧２００ｋＶの条件で測定試料の格子像を観察し、ニッケル粉末表面の酸化ニッケル及び水酸化ニッケルの被膜厚さを６点測定し、その平均を算出した。
６）２％熱収縮温度及び焼結挙動
ニッケル粉末１ｇ、しょうのう３重量％およびアセトン３重量％を混合し、内径５ｍｍ、長さ１０ｍｍの円柱状の金型に充填し、その後面圧１トンの荷重をかけ試験ピースを作成した。この試験ピースを、熱膨張収縮挙動（ｄｉｒａｔｏｍｅｔｒｙ）測定装置（ＴＭＡ、８３１０、株式会社リガク社製）を用い、窒素ガス（水素ガス２％含有）の雰囲気下で昇温速度１０℃／分の条件で測定を行った。また、熱膨張収縮挙動測定装置（ＴＭＡ）により測定される２％熱収縮の温度を２％熱収縮温度とした。
７）比表面積
ＢＥＴ比表面積測定装置（株式会社マウンテック社製）を用いて、窒素気流下で１６０℃、１時間の前処理後、比表面積測定を行い、その比表面積Ｓから、下記式（式１）を用いて比表面積径ｄを算出した。ここで、ρはニッケルの真密度である。さらに、個数平均粒子径Ｄと比表面積径ｄの比を算出した。 Measurement Oxygen content, average particle diameter, nickel metal and surface oxide by surface X-ray photoelectron spectroscopy (XPS), surface hydroxide ratio, dispersibility evaluation, oxidation The method for measuring the thickness of the nickel and nickel hydroxide coatings and the 2% heat shrinkage temperature is shown below.
1) Oxygen content The nickel powder of the sample is filled in a nickel capsule, put in a graphite crucible, heated to 500 ° C. in an argon atmosphere, and the carbon monoxide generated at this time is Fourier-transform infrared spectrophotometric. It quantified with the meter and calculated | required the oxygen content rate in nickel powder.
2) Average particle diameter A photograph of the sample was taken with an electron microscope, and using the image analysis software, the particle diameter of 900 powders was measured and the number average particle diameter was calculated. At this time, the particle diameter is the diameter of the smallest circle that encloses the particles.
3) X-ray photoelectron spectroscopic analysis (XPS) measurement Using an X-ray photoelectron spectroscopic analyzer (manufactured by Thermo Fisher Scientific Co., Ltd., K-ALPHA + ), the Ni2p 3/2 spectrum of the powder surface is measured and the analyzer is used. Using the attached analysis software “Avantage Ver. 5.951”, the spectrum is peak-separated, the peak of metallic nickel with respect to the entire Ni2p 3/2 spectrum, the peak attributed to the combined state of nickel and oxygen, nickel and water The area ratio of peaks attributed to the oxide bonding state was calculated.
4) Dispersibility evaluation 0.05 g of nickel powder was put in 100 g of pure water, and dispersed for 1 minute with an ultrasonic disperser (Sonic Technology Co., Ltd., GSD600AT). After sample dispersion treatment, vacuum filtration was performed using a 3 μm membrane filter. If the time taken for the slurry to pass through the membrane filter was within 30 seconds (◯), it took more than 30 seconds. In the case, it was regarded as defective (x).
5) Thickness of nickel oxide and nickel hydroxide film Nickel powder was directly sprinkled on a copper sheet mesh covered with a collodion film, and then carbon was deposited to prepare a measurement sample. Next, using a transmission electron microscope (manufactured by JEOL Ltd., JEM-2100F), the lattice image of the measurement sample was observed under the condition of an acceleration voltage of 200 kV, and the film thicknesses of nickel oxide and nickel hydroxide on the surface of the nickel powder were measured. Six points were measured and the average was calculated.
6) 2% heat shrinkage temperature and sintering behavior 1 g of nickel powder, 3% by weight of camphor and 3% by weight of acetone are mixed and filled into a cylindrical mold having an inner diameter of 5 mm and a length of 10 mm. A test piece was prepared by applying a load of tons. Using this test piece, a thermal dilatometry measuring device (TMA, 8310, manufactured by Rigaku Co., Ltd.), under a nitrogen gas atmosphere (containing 2% hydrogen gas), a temperature rising rate of 10 ° C./min. The measurement was performed. Further, the temperature of 2% heat shrinkage measured by a thermal expansion / shrinkage behavior measuring apparatus (TMA) was defined as 2% heat shrinkage temperature.
7) Specific surface area Using a BET specific surface area measuring device (manufactured by Mountec Co., Ltd.), a specific surface area is measured after pretreatment at 160 ° C. for 1 hour under a nitrogen stream. The specific surface area diameter d was calculated using 1). Here, ρ is the true density of nickel. Furthermore, the ratio of the number average particle diameter D and the specific surface area diameter d was calculated.
表１から明らかなように、比較例１、２のニッケル粉末よりも表面酸化物の割合が高い実施例１のニッケル粉末では、同様に表面酸化物の割合が高い比較例３のニッケル粉末より分散性評価が優れていた。このことから、実施例１のニッケル粉末は分散性が優れているため、積層セラミックコンデンサを製造する際にニッケル粉と共材との混合が十分となり、デラミネーションの防止が図られることが推定される。
As is apparent from Table 1, the nickel powder of Example 1 having a higher surface oxide ratio than the nickel powders of Comparative Examples 1 and 2 is more dispersed than the nickel powder of Comparative Example 3 having a higher surface oxide ratio. The sex evaluation was excellent. From this, since the nickel powder of Example 1 is excellent in dispersibility, it is presumed that mixing of the nickel powder and the common material becomes sufficient when the multilayer ceramic capacitor is manufactured, and delamination is prevented. The
また、実施例１のニッケル粉末の被膜の厚さは比較例１、２のニッケル粉末よりも大きいことが分かる。
It can also be seen that the thickness of the nickel powder coating of Example 1 is larger than that of Comparative Examples 1 and 2.
さらに２％熱収縮温度において、実施例１のニッケル粉末は比較例１、２のニッケル粉末よりも高く、また、図１の焼結挙動において、３００～４００℃の低温領域での体積変化が全くなく焼結挙動が安定している。
Furthermore, at 2% heat shrinkage temperature, the nickel powder of Example 1 is higher than the nickel powders of Comparative Examples 1 and 2, and the volume change in the low temperature region of 300 to 400 ° C. is completely observed in the sintering behavior of FIG. Sintering behavior is stable.
以上の結果から、本発明のニッケル粉末は、積層セラミックコンデンサの製造工程において優れた焼結挙動を示し、また分散性に優れているため、結果として、デラミネーションの防止が図られることが推定される。
From the above results, it is estimated that the nickel powder of the present invention exhibits excellent sintering behavior in the production process of the multilayer ceramic capacitor and is excellent in dispersibility, and as a result, prevention of delamination can be achieved. The
以上説明したように、本発明のニッケル粉末によれば、平均粒径２５０ｎｍ以下において、焼結挙動が従来のニッケル粉末に比べて非常に安定しており、低温領域でのニッケル粉末の収縮および膨張がなく、また分散性に優れており、従って、本発明のニッケル粉末を使用したペーストは、積層セラミックコンデンサの製造過程においてデラミネーションの発生を防止することができるという効果を奏する。
As described above, according to the nickel powder of the present invention, the sintering behavior is very stable as compared with the conventional nickel powder at an average particle size of 250 nm or less, and the shrinkage and expansion of the nickel powder in the low temperature region. In addition, the paste using the nickel powder of the present invention has an effect of preventing the occurrence of delamination in the manufacturing process of the multilayer ceramic capacitor.
本発明によれば、焼結挙動が従来のニッケル粉末に比べて非常に安定しており、低温領域でのニッケル粉末の収縮および膨張がなく、また、分散性に優れており、ＭＬＣＣの製造に好適なニッケル粉を提供することができる。
According to the present invention, the sintering behavior is very stable compared to the conventional nickel powder, there is no shrinkage and expansion of the nickel powder in the low temperature region, and the dispersibility is excellent. A suitable nickel powder can be provided.
Claims (1)
- 酸化ニッケル及び水酸化ニッケルを含む被膜を有し、平均粒径が２５０ｎｍ以下であり、Ｘ線光電子分光法（ＸＰＳ）によるニッケル粉末表面層のニッケルの化学結合状態の解析において、ニッケルと酸素の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５５．０～８０．０％、金属ニッケルのピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～１５．０％、ニッケルと水酸基の結合状態に帰属されるピークのＮｉ２ｐ３／２スペクトル全体に対する面積比が５．０～４０．０％であって、前記被膜の厚さの平均が３．０～５．０ｎｍであることを特徴とするニッケル粉末。 In the analysis of the chemical bonding state of nickel in the surface layer of nickel powder by X-ray photoelectron spectroscopy (XPS) having a coating containing nickel oxide and nickel hydroxide and having an average particle size of 250 nm or less, the bond between nickel and oxygen The area ratio of the peak attributed to the state to the entire Ni2p 3/2 spectrum is 55.0 to 80.0%, the area ratio of the peak of metallic nickel to the entire Ni2p 3/2 spectrum is 5.0 to 15.0%, The area ratio of the peak attributed to the bonded state of nickel and hydroxyl group to the entire Ni2p 3/2 spectrum is 5.0 to 40.0%, and the average thickness of the coating is 3.0 to 5.0 nm. Nickel powder characterized by being.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020187023021A KR102589697B1 (en) | 2016-01-12 | 2017-01-11 | nickel powder |
| CN201780006541.7A CN108430673B (en) | 2016-01-12 | 2017-01-11 | Nickel powder |
| JP2017561140A JP6876001B2 (en) | 2016-01-12 | 2017-01-11 | Nickel powder manufacturing method |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2016-003879 | 2016-01-12 | ||
| JP2016003879 | 2016-01-12 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2017122689A1 true WO2017122689A1 (en) | 2017-07-20 |
Family
ID=59310928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/JP2017/000660 WO2017122689A1 (en) | 2016-01-12 | 2017-01-11 | Nickel powder |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JP6876001B2 (en) |
| KR (1) | KR102589697B1 (en) |
| CN (1) | CN108430673B (en) |
| TW (1) | TWI716526B (en) |
| WO (1) | WO2017122689A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019187688A1 (en) * | 2018-03-29 | 2019-10-03 | 東邦チタニウム株式会社 | Nickel powder and production method therefor |
| JP2021050384A (en) * | 2019-09-25 | 2021-04-01 | 大陽日酸株式会社 | Manufacturing method of nickel fine particles |
| US20220250144A1 (en) * | 2019-07-31 | 2022-08-11 | Sumitomo Metal Mining Co., Ltd. | Nickel powder and method for producing nickel powder |
| WO2025070243A1 (en) * | 2023-09-28 | 2025-04-03 | 株式会社村田製作所 | Conductive paste |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112423912B (en) * | 2018-06-28 | 2023-05-23 | 东邦钛株式会社 | Metal powder, method for producing same, and method for predicting sintering temperature |
| JP7251068B2 (en) * | 2018-07-31 | 2023-04-04 | 住友金属鉱山株式会社 | Composition for thick film resistor, paste for thick film resistor, and thick film resistor |
| CN112872349A (en) * | 2021-01-12 | 2021-06-01 | 杭州新川新材料有限公司 | Nano nickel powder with core-shell structure |
| CN113270270B (en) * | 2021-05-27 | 2022-04-05 | 广东省先进陶瓷材料科技有限公司 | Anti-oxidation nickel slurry and preparation method and application thereof |
| US12154721B2 (en) | 2021-09-14 | 2024-11-26 | Samsung Electro-Mechanics Co., Ltd. | Multilayer electronic component, and method of manufacturing the same |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004330247A (en) * | 2003-05-08 | 2004-11-25 | Murata Mfg Co Ltd | Nickel powder, conductive paste, laminate ceramic electronic component |
| JP2011149080A (en) * | 2010-01-25 | 2011-08-04 | Sumitomo Metal Mining Co Ltd | Nickel powder and production method therefor |
| JP2014029014A (en) * | 2012-04-04 | 2014-02-13 | Nippon Steel & Sumikin Chemical Co Ltd | Complex nickel particle |
| JP2015086465A (en) * | 2013-10-30 | 2015-05-07 | サムソン エレクトロ−メカニックス カンパニーリミテッド． | Nickel nanopowder and production method thereof |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3197454B2 (en) | 1995-03-10 | 2001-08-13 | 川崎製鉄株式会社 | Ultra fine nickel powder for multilayer ceramic capacitors |
| JP3984712B2 (en) | 1998-07-27 | 2007-10-03 | 東邦チタニウム株式会社 | Nickel powder for conductive paste |
| US6391084B1 (en) | 1998-07-27 | 2002-05-21 | Toho Titanium Co., Ltd. | Metal nickel powder |
| KR101014158B1 (en) * | 2002-08-28 | 2011-02-14 | 도호 티타늄 가부시키가이샤 | Metallic nickel powder and its manufacturing method |
| KR100682884B1 (en) * | 2003-04-08 | 2007-02-15 | 삼성전자주식회사 | Nickel metal powder and its manufacturing method |
| WO2005123307A1 (en) * | 2004-06-16 | 2005-12-29 | Toho Titanium Co., Ltd. | Nickel powder and manufacturing method thereof |
| JP4697539B2 (en) * | 2005-12-07 | 2011-06-08 | 昭栄化学工業株式会社 | Nickel powder, conductor paste and laminated electronic component using the same |
| JP4807581B2 (en) * | 2007-03-12 | 2011-11-02 | 昭栄化学工業株式会社 | Nickel powder, method for producing the same, conductor paste, and multilayer ceramic electronic component using the same |
| WO2011037150A1 (en) * | 2009-09-24 | 2011-03-31 | 住友金属鉱山株式会社 | Nickel powder and production method thereof |
| DK2740711T3 (en) * | 2011-08-06 | 2017-01-09 | Sumitomo Metal Mining Co | Nikkeloxidmikropulver and process for their preparation. |
| TWI597112B (en) * | 2012-04-06 | 2017-09-01 | 東邦鈦股份有限公司 | Nickel metal powder and process for production thereof |
| KR101689491B1 (en) * | 2012-11-20 | 2016-12-23 | 제이에프이미네라르 가부시키가이샤 | Nickel powder, conductive paste, and laminated ceramic electronic component |
| KR102292897B1 (en) * | 2014-04-08 | 2021-08-24 | 도호 티타늄 가부시키가이샤 | Nickel powder |
| JP6292014B2 (en) * | 2014-05-12 | 2018-03-14 | 株式会社村田製作所 | Conductive paste and ceramic electronic components |
-
2017
- 2017-01-11 TW TW106100782A patent/TWI716526B/en active
- 2017-01-11 KR KR1020187023021A patent/KR102589697B1/en active Active
- 2017-01-11 JP JP2017561140A patent/JP6876001B2/en active Active
- 2017-01-11 CN CN201780006541.7A patent/CN108430673B/en active Active
- 2017-01-11 WO PCT/JP2017/000660 patent/WO2017122689A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004330247A (en) * | 2003-05-08 | 2004-11-25 | Murata Mfg Co Ltd | Nickel powder, conductive paste, laminate ceramic electronic component |
| JP2011149080A (en) * | 2010-01-25 | 2011-08-04 | Sumitomo Metal Mining Co Ltd | Nickel powder and production method therefor |
| JP2014029014A (en) * | 2012-04-04 | 2014-02-13 | Nippon Steel & Sumikin Chemical Co Ltd | Complex nickel particle |
| JP2015086465A (en) * | 2013-10-30 | 2015-05-07 | サムソン エレクトロ−メカニックス カンパニーリミテッド． | Nickel nanopowder and production method thereof |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019187688A1 (en) * | 2018-03-29 | 2019-10-03 | 東邦チタニウム株式会社 | Nickel powder and production method therefor |
| JP6647458B1 (en) * | 2018-03-29 | 2020-02-14 | 東邦チタニウム株式会社 | Nickel powder and method for producing the same |
| KR20200111791A (en) * | 2018-03-29 | 2020-09-29 | 도호 티타늄 가부시키가이샤 | Nickel powder and its manufacturing method |
| CN111936254A (en) * | 2018-03-29 | 2020-11-13 | 东邦钛株式会社 | Nickel powder and method for producing same |
| KR102352835B1 (en) | 2018-03-29 | 2022-01-18 | 도호 티타늄 가부시키가이샤 | Nickel powder and its manufacturing method |
| CN111936254B (en) * | 2018-03-29 | 2023-02-28 | 东邦钛株式会社 | Nickel powder and method for producing same |
| US20220250144A1 (en) * | 2019-07-31 | 2022-08-11 | Sumitomo Metal Mining Co., Ltd. | Nickel powder and method for producing nickel powder |
| US11850665B2 (en) * | 2019-07-31 | 2023-12-26 | Sumitomo Metal Mining Co., Ltd. | Nickel powder and method for producing nickel powder |
| JP2021050384A (en) * | 2019-09-25 | 2021-04-01 | 大陽日酸株式会社 | Manufacturing method of nickel fine particles |
| JP7341820B2 (en) | 2019-09-25 | 2023-09-11 | 大陽日酸株式会社 | Method for producing nickel fine particles |
| WO2025070243A1 (en) * | 2023-09-28 | 2025-04-03 | 株式会社村田製作所 | Conductive paste |
Also Published As
| Publication number | Publication date |
|---|---|
| JPWO2017122689A1 (en) | 2018-11-01 |
| CN108430673A (en) | 2018-08-21 |
| JP6876001B2 (en) | 2021-05-26 |
| TWI716526B (en) | 2021-01-21 |
| KR102589697B1 (en) | 2023-10-16 |
| TW201736617A (en) | 2017-10-16 |
| KR20180101504A (en) | 2018-09-12 |
| CN108430673B (en) | 2021-09-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2017122689A1 (en) | Nickel powder | |
| US7658995B2 (en) | Nickel powder comprising sulfur and carbon, and production method therefor | |
| JP4286220B2 (en) | Metallic nickel powder and method for producing the same | |
| JP7042372B2 (en) | Nickel powder and its manufacturing method, nickel paste | |
| TWI584891B (en) | A metal powder coated with carbon, a conductive paste containing a metal powder coated with carbon, and a method for producing a metal powder coated with a metal powder and a metal powder coated with the same | |
| JP6559118B2 (en) | Nickel powder | |
| KR101509878B1 (en) | Composite powders of metal-ceramic core-shell structure for multilayer ceramic capacitors synthesized by gas phase processes and their preparation | |
| JP6425367B1 (en) | Nickel powder and nickel paste | |
| JP3812359B2 (en) | Method for producing metal powder | |
| JP4540364B2 (en) | Nickel powder, and conductive paste and multilayer ceramic capacitor using the same | |
| JP2005240076A (en) | Method for manufacturing oxide-containing nickel powder | |
| JP2004263205A (en) | Metallic impalpable powder, manufacturing method therefor, and conductive paste using the metallic impalpable powder | |
| JP4276031B2 (en) | Titanium compound-coated nickel powder and conductive paste using the same | |
| JP2006037195A (en) | Method for producing nickel powder | |
| JP2024124772A (en) | Nickel powder manufacturing method and its use | |
| JP2005240075A (en) | Method for producing oxide-containing nickel powder | |
| JP2013231229A (en) | Nickel composite particle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 17738443 Country of ref document: EP Kind code of ref document: A1 |
|
| ENP | Entry into the national phase |
Ref document number: 2017561140 Country of ref document: JP Kind code of ref document: A |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| ENP | Entry into the national phase |
Ref document number: 20187023021 Country of ref document: KR Kind code of ref document: A |
|
| WWE | Wipo information: entry into national phase |
Ref document number: 1020187023021 Country of ref document: KR |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 17738443 Country of ref document: EP Kind code of ref document: A1 |