JPH0578926B2 - - Google Patents
Info
- Publication number
- JPH0578926B2 JPH0578926B2 JP60001672A JP167285A JPH0578926B2 JP H0578926 B2 JPH0578926 B2 JP H0578926B2 JP 60001672 A JP60001672 A JP 60001672A JP 167285 A JP167285 A JP 167285A JP H0578926 B2 JPH0578926 B2 JP H0578926B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic powder
- coated
- iron
- metal
- acicular fine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000006247 magnetic powder Substances 0.000 claims description 143
- 229910052751 metal Inorganic materials 0.000 claims description 77
- 239000002184 metal Substances 0.000 claims description 77
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 36
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 33
- 238000000576 coating method Methods 0.000 claims description 30
- 239000002738 chelating agent Substances 0.000 claims description 27
- 239000011248 coating agent Substances 0.000 claims description 24
- 229910052802 copper Inorganic materials 0.000 claims description 15
- 229910052759 nickel Inorganic materials 0.000 claims description 14
- 230000001590 oxidative effect Effects 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 189
- 229910052742 iron Inorganic materials 0.000 description 91
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 64
- 239000010419 fine particle Substances 0.000 description 54
- 239000002245 particle Substances 0.000 description 50
- 230000003647 oxidation Effects 0.000 description 37
- 238000007254 oxidation reaction Methods 0.000 description 37
- 239000000843 powder Substances 0.000 description 36
- 239000010949 copper Substances 0.000 description 31
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 30
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 30
- 230000009920 chelation Effects 0.000 description 26
- 230000000052 comparative effect Effects 0.000 description 23
- JZQOJFLIJNRDHK-CMDGGOBGSA-N alpha-irone Chemical compound CC1CC=C(C)C(\C=C\C(C)=O)C1(C)C JZQOJFLIJNRDHK-CMDGGOBGSA-N 0.000 description 22
- 229910000859 α-Fe Inorganic materials 0.000 description 22
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 20
- 239000011575 calcium Substances 0.000 description 20
- 229910052791 calcium Inorganic materials 0.000 description 20
- 239000000725 suspension Substances 0.000 description 18
- 239000000243 solution Substances 0.000 description 17
- YRKCREAYFQTBPV-UHFFFAOYSA-N acetylacetone Chemical compound CC(=O)CC(C)=O YRKCREAYFQTBPV-UHFFFAOYSA-N 0.000 description 16
- 229910001111 Fine metal Inorganic materials 0.000 description 15
- 230000005415 magnetization Effects 0.000 description 15
- CUPCBVUMRUSXIU-UHFFFAOYSA-N [Fe].OOO Chemical compound [Fe].OOO CUPCBVUMRUSXIU-UHFFFAOYSA-N 0.000 description 14
- 229910021519 iron(III) oxide-hydroxide Inorganic materials 0.000 description 14
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 12
- 239000007864 aqueous solution Substances 0.000 description 11
- 239000000203 mixture Substances 0.000 description 11
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 10
- 239000007789 gas Substances 0.000 description 10
- -1 aluminum compound Chemical class 0.000 description 9
- BFDHFSHZJLFAMC-UHFFFAOYSA-L nickel(ii) hydroxide Chemical compound [OH-].[OH-].[Ni+2] BFDHFSHZJLFAMC-UHFFFAOYSA-L 0.000 description 9
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 7
- 239000002253 acid Substances 0.000 description 6
- 239000001569 carbon dioxide Substances 0.000 description 6
- 229910002092 carbon dioxide Inorganic materials 0.000 description 6
- 230000007423 decrease Effects 0.000 description 6
- 229910021506 iron(II) hydroxide Inorganic materials 0.000 description 6
- NGHMEZWZOZEZOH-UHFFFAOYSA-N silicic acid;hydrate Chemical compound O.O[Si](O)(O)O NGHMEZWZOZEZOH-UHFFFAOYSA-N 0.000 description 6
- 239000013522 chelant Substances 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 5
- 238000001035 drying Methods 0.000 description 5
- 239000011521 glass Substances 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 150000002815 nickel Chemical class 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- JJLJMEJHUUYSSY-UHFFFAOYSA-L Copper hydroxide Chemical compound [OH-].[OH-].[Cu+2] JJLJMEJHUUYSSY-UHFFFAOYSA-L 0.000 description 4
- 238000007664 blowing Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 229910021645 metal ion Inorganic materials 0.000 description 4
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 4
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- MXRIRQGCELJRSN-UHFFFAOYSA-N O.O.O.[Al] Chemical compound O.O.O.[Al] MXRIRQGCELJRSN-UHFFFAOYSA-N 0.000 description 3
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- 125000003118 aryl group Chemical group 0.000 description 3
- 150000001879 copper Chemical class 0.000 description 3
- 238000000151 deposition Methods 0.000 description 3
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 3
- 229920006395 saturated elastomer Polymers 0.000 description 3
- 239000005750 Copper hydroxide Substances 0.000 description 2
- DHMQDGOQFOQNFH-UHFFFAOYSA-N Glycine Chemical compound NCC(O)=O DHMQDGOQFOQNFH-UHFFFAOYSA-N 0.000 description 2
- 229910021586 Nickel(II) chloride Inorganic materials 0.000 description 2
- 239000012670 alkaline solution Substances 0.000 description 2
- 125000000217 alkyl group Chemical group 0.000 description 2
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 description 2
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 2
- 150000001412 amines Chemical class 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 229910001956 copper hydroxide Inorganic materials 0.000 description 2
- 229910000365 copper sulfate Inorganic materials 0.000 description 2
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- 235000003891 ferrous sulphate Nutrition 0.000 description 2
- 239000011790 ferrous sulphate Substances 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 230000001771 impaired effect Effects 0.000 description 2
- 150000002505 iron Chemical class 0.000 description 2
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- QMMRZOWCJAIUJA-UHFFFAOYSA-L nickel dichloride Chemical compound Cl[Ni]Cl QMMRZOWCJAIUJA-UHFFFAOYSA-L 0.000 description 2
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 description 2
- 235000019353 potassium silicate Nutrition 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 2
- POWFTOSLLWLEBN-UHFFFAOYSA-N tetrasodium;silicate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-][Si]([O-])([O-])[O-] POWFTOSLLWLEBN-UHFFFAOYSA-N 0.000 description 2
- BNGXYYYYKUGPPF-UHFFFAOYSA-M (3-methylphenyl)methyl-triphenylphosphanium;chloride Chemical compound [Cl-].CC1=CC=CC(C[P+](C=2C=CC=CC=2)(C=2C=CC=CC=2)C=2C=CC=CC=2)=C1 BNGXYYYYKUGPPF-UHFFFAOYSA-M 0.000 description 1
- CVBUKMMMRLOKQR-UHFFFAOYSA-N 1-phenylbutane-1,3-dione Chemical compound CC(=O)CC(=O)C1=CC=CC=C1 CVBUKMMMRLOKQR-UHFFFAOYSA-N 0.000 description 1
- NROOHYGFTHTDFF-UHFFFAOYSA-N 1-phenylpentane-2,4-dione Chemical compound CC(=O)CC(=O)CC1=CC=CC=C1 NROOHYGFTHTDFF-UHFFFAOYSA-N 0.000 description 1
- ZYXNLVMBIHVDRH-UHFFFAOYSA-N 2-Methylpropyl 3-oxobutanoate Chemical compound CC(C)COC(=O)CC(C)=O ZYXNLVMBIHVDRH-UHFFFAOYSA-N 0.000 description 1
- DJHGZIHTRHTINN-UHFFFAOYSA-N 2-[[4,6-bis[bis(carboxymethyl)amino]-1,3,5-triazin-2-yl]-(carboxymethyl)amino]acetic acid Chemical compound OC(=O)CN(CC(O)=O)C1=NC(N(CC(O)=O)CC(O)=O)=NC(N(CC(O)=O)CC(O)=O)=N1 DJHGZIHTRHTINN-UHFFFAOYSA-N 0.000 description 1
- VWQDAWBPARHBRC-UHFFFAOYSA-N 2-hydroxybenzaldehyde;propane-1,2-diamine Chemical compound CC(N)CN.OC1=CC=CC=C1C=O.OC1=CC=CC=C1C=O VWQDAWBPARHBRC-UHFFFAOYSA-N 0.000 description 1
- ONGBXISBKSVVFS-UHFFFAOYSA-N 2-methyl-1,3-diphenylpropane-1,3-dione Chemical compound C=1C=CC=CC=1C(=O)C(C)C(=O)C1=CC=CC=C1 ONGBXISBKSVVFS-UHFFFAOYSA-N 0.000 description 1
- IRNJRGVFXLVQEK-UHFFFAOYSA-N 2-methyl-1-phenylbutane-1,3-dione Chemical compound CC(=O)C(C)C(=O)C1=CC=CC=C1 IRNJRGVFXLVQEK-UHFFFAOYSA-N 0.000 description 1
- TXPKUUXHNFRBPS-UHFFFAOYSA-N 3-(2-carboxyethylamino)propanoic acid Chemical compound OC(=O)CCNCCC(O)=O TXPKUUXHNFRBPS-UHFFFAOYSA-N 0.000 description 1
- KWYJDIUEHHCHCZ-UHFFFAOYSA-N 3-[2-[bis(2-carboxyethyl)amino]ethyl-(2-carboxyethyl)amino]propanoic acid Chemical compound OC(=O)CCN(CCC(O)=O)CCN(CCC(O)=O)CCC(O)=O KWYJDIUEHHCHCZ-UHFFFAOYSA-N 0.000 description 1
- GUEHWIHSYRXNNA-UHFFFAOYSA-N 3-acetylpentane-2,4-dione;benzene-1,2-diamine Chemical compound NC1=CC=CC=C1N.CC(=O)C(C(C)=O)C(C)=O GUEHWIHSYRXNNA-UHFFFAOYSA-N 0.000 description 1
- GSOHKPVFCOWKPU-UHFFFAOYSA-N 3-methylpentane-2,4-dione Chemical compound CC(=O)C(C)C(C)=O GSOHKPVFCOWKPU-UHFFFAOYSA-N 0.000 description 1
- REIYHFWZISXFKU-UHFFFAOYSA-N Butyl acetoacetate Chemical compound CCCCOC(=O)CC(C)=O REIYHFWZISXFKU-UHFFFAOYSA-N 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 1
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 description 1
- 229930194542 Keto Natural products 0.000 description 1
- WRQNANDWMGAFTP-UHFFFAOYSA-N Methylacetoacetic acid Chemical compound COC(=O)CC(C)=O WRQNANDWMGAFTP-UHFFFAOYSA-N 0.000 description 1
- 239000002262 Schiff base Substances 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 150000001447 alkali salts Chemical class 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 150000004645 aluminates Chemical class 0.000 description 1
- ANBBXQWFNXMHLD-UHFFFAOYSA-N aluminum;sodium;oxygen(2-) Chemical compound [O-2].[O-2].[Na+].[Al+3] ANBBXQWFNXMHLD-UHFFFAOYSA-N 0.000 description 1
- PWRSNLQOHLSQCA-UHFFFAOYSA-N benzene-1,2-diamine;2-hydroxybenzaldehyde Chemical compound NC1=CC=CC=C1N.OC1=CC=CC=C1C=O.OC1=CC=CC=C1C=O PWRSNLQOHLSQCA-UHFFFAOYSA-N 0.000 description 1
- UCMIRNVEIXFBKS-UHFFFAOYSA-N beta-alanine Chemical compound NCCC(O)=O UCMIRNVEIXFBKS-UHFFFAOYSA-N 0.000 description 1
- 150000001728 carbonyl compounds Chemical class 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 239000003638 chemical reducing agent 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
- 150000001875 compounds Chemical class 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229940116318 copper carbonate Drugs 0.000 description 1
- XTVVROIMIGLXTD-UHFFFAOYSA-N copper(II) nitrate Chemical compound [Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O XTVVROIMIGLXTD-UHFFFAOYSA-N 0.000 description 1
- GEZOTWYUIKXWOA-UHFFFAOYSA-L copper;carbonate Chemical compound [Cu+2].[O-]C([O-])=O GEZOTWYUIKXWOA-UHFFFAOYSA-L 0.000 description 1
- CLCYRHCSVWOLHG-UHFFFAOYSA-N decyl 3-oxobutanoate Chemical compound CCCCCCCCCCOC(=O)CC(C)=O CLCYRHCSVWOLHG-UHFFFAOYSA-N 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- NZZIMKJIVMHWJC-UHFFFAOYSA-N dibenzoylmethane Chemical compound C=1C=CC=CC=1C(=O)CC(=O)C1=CC=CC=C1 NZZIMKJIVMHWJC-UHFFFAOYSA-N 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- SQFYHAFSDZOUDE-UHFFFAOYSA-N ethane-1,2-diamine;2-hydroxybenzaldehyde Chemical compound NCCN.OC1=CC=CC=C1C=O.OC1=CC=CC=C1C=O SQFYHAFSDZOUDE-UHFFFAOYSA-N 0.000 description 1
- XYIBRDXRRQCHLP-UHFFFAOYSA-N ethyl acetoacetate Chemical compound CCOC(=O)CC(C)=O XYIBRDXRRQCHLP-UHFFFAOYSA-N 0.000 description 1
- 229960002449 glycine Drugs 0.000 description 1
- 235000013905 glycine and its sodium salt Nutrition 0.000 description 1
- ILPNRWUGFSPGAA-UHFFFAOYSA-N heptane-2,4-dione Chemical compound CCCC(=O)CC(C)=O ILPNRWUGFSPGAA-UHFFFAOYSA-N 0.000 description 1
- DGCTVLNZTFDPDJ-UHFFFAOYSA-N heptane-3,5-dione Chemical compound CCC(=O)CC(=O)CC DGCTVLNZTFDPDJ-UHFFFAOYSA-N 0.000 description 1
- NDOGLIPWGGRQCO-UHFFFAOYSA-N hexane-2,4-dione Chemical compound CCC(=O)CC(C)=O NDOGLIPWGGRQCO-UHFFFAOYSA-N 0.000 description 1
- QNZLAXONNWOLJY-UHFFFAOYSA-N hexyl 3-oxobutanoate Chemical compound CCCCCCOC(=O)CC(C)=O QNZLAXONNWOLJY-UHFFFAOYSA-N 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- NBZBKCUXIYYUSX-UHFFFAOYSA-N iminodiacetic acid Chemical compound OC(=O)CNCC(O)=O NBZBKCUXIYYUSX-UHFFFAOYSA-N 0.000 description 1
- FBAFATDZDUQKNH-UHFFFAOYSA-M iron chloride Chemical compound [Cl-].[Fe] FBAFATDZDUQKNH-UHFFFAOYSA-M 0.000 description 1
- 235000014413 iron hydroxide Nutrition 0.000 description 1
- 159000000014 iron salts Chemical class 0.000 description 1
- 229910000358 iron sulfate Inorganic materials 0.000 description 1
- MVFCKEFYUDZOCX-UHFFFAOYSA-N iron(2+);dinitrate Chemical compound [Fe+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MVFCKEFYUDZOCX-UHFFFAOYSA-N 0.000 description 1
- 125000000468 ketone group Chemical group 0.000 description 1
- 239000003446 ligand Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- MGFYIUFZLHCRTH-UHFFFAOYSA-N nitrilotriacetic acid Chemical compound OC(=O)CN(CC(O)=O)CC(O)=O MGFYIUFZLHCRTH-UHFFFAOYSA-N 0.000 description 1
- OXMOJULFKLVWDY-UHFFFAOYSA-N nonyl 3-oxobutanoate Chemical compound CCCCCCCCCOC(=O)CC(C)=O OXMOJULFKLVWDY-UHFFFAOYSA-N 0.000 description 1
- GJYXGIIWJFZCLN-UHFFFAOYSA-N octane-2,4-dione Chemical compound CCCCC(=O)CC(C)=O GJYXGIIWJFZCLN-UHFFFAOYSA-N 0.000 description 1
- SMQUZDBALVYZAC-UHFFFAOYSA-N ortho-hydroxybenzaldehyde Natural products OC1=CC=CC=C1C=O SMQUZDBALVYZAC-UHFFFAOYSA-N 0.000 description 1
- IDZAUPYMMSSVHP-UHFFFAOYSA-N pentyl 3-oxobutanoate Chemical compound CCCCCOC(=O)CC(C)=O IDZAUPYMMSSVHP-UHFFFAOYSA-N 0.000 description 1
- 150000003014 phosphoric acid esters Chemical class 0.000 description 1
- 229910052913 potassium silicate Inorganic materials 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- GVIIRWAJDFKJMJ-UHFFFAOYSA-N propan-2-yl 3-oxobutanoate Chemical compound CC(C)OC(=O)CC(C)=O GVIIRWAJDFKJMJ-UHFFFAOYSA-N 0.000 description 1
- MEDDTFWQBUNCSE-UHFFFAOYSA-N propanoic acid;1,3,5-triazine-2,4,6-triamine Chemical compound CCC(O)=O.CCC(O)=O.CCC(O)=O.CCC(O)=O.CCC(O)=O.CCC(O)=O.NC1=NC(N)=NC(N)=N1 MEDDTFWQBUNCSE-UHFFFAOYSA-N 0.000 description 1
- DHGFMVMDBNLMKT-UHFFFAOYSA-N propyl 3-oxobutanoate Chemical compound CCCOC(=O)CC(C)=O DHGFMVMDBNLMKT-UHFFFAOYSA-N 0.000 description 1
- 150000004760 silicates Chemical class 0.000 description 1
- 239000000344 soap Substances 0.000 description 1
- 229910001388 sodium aluminate Inorganic materials 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 235000019795 sodium metasilicate Nutrition 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 238000013112 stability test Methods 0.000 description 1
- 238000005486 sulfidation Methods 0.000 description 1
- 150000003871 sulfonates Chemical class 0.000 description 1
- 238000010301 surface-oxidation reaction Methods 0.000 description 1
- JKUYRAMKJLMYLO-UHFFFAOYSA-N tert-butyl 3-oxobutanoate Chemical compound CC(=O)CC(=O)OC(C)(C)C JKUYRAMKJLMYLO-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/06—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder
- H01F1/061—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder with a protective layer
Description
〔産業上の利用分野〕
この発明は磁気記録媒体用として好適な金属磁
性粉末に関し、さらに詳しくは酸化安定性に優れ
た前記の金属磁性粉末に関する。
〔従来の技術〕
鉄、ニツケル、コバルト等の金属磁性粉末は従
来の酸化物系磁性粉末に比較して優れた磁気特性
を有しているが、反面粉末粒子表面が非常に活性
なため空気中で非常に酸化を受け易く、酸化安定
性に欠け、飽和磁化量が経時的に低下するという
難点がある。
このような欠点を改善するため、従来から金属
磁性粉末の粒子表面を酸化して酸化物被膜を設け
るか（特公昭56−28961号公報）、あるいは高級脂
肪族の、カルボン酸、金属石鹸、スルフオン酸、
アミン、リン酸エステル、エステル等の有機防食
剤で処理してこれらの被膜を設ける（特公昭58−
54485号公報）などの方法で酸化安定性を向上す
ることが行われている。
〔発明が解決しようとする問題点〕
ところが、金属磁性粉末の粒子表面の酸化によ
つて酸化安定性を図る方法では、充分な酸化安定
性を確保しようとすると粒子表面の酸化物被膜の
厚みを厚くしなければならず、そのため磁性粉末
の磁化量が減少し、特に磁性粉末が微細なものほ
どこの表面酸化による磁化量の低下が著しく、微
細な金属磁性粉末の特徴である高い磁化量が保持
できなくなるという難点がある。また有機防食剤
で金属磁性粉末の粒子表面を処理する方法では、
これらの有機防食剤の金属イオンとの結合力がそ
れほど強くないため充分な防食効果が発揮され
ず、未だ充分な酸化安定性は得られていない。
〔問題点を解決するための手段〕
この発明はかかる現状に鑑み、種々検討を行つ
た結果、金属磁性粉末に、SiO2、Al2O3、Ni3Fe、
Cu、Niから選ばれる少なくとも１種からなる被
膜を設け、次いでこれをキレート化剤で処理して
その粒子表面にキレート化剤を存在させると、酸
素ガス等のアタツクが強力に防止されて、酸化安
定性に優れた金属磁性粉末が得られ、さらに金属
磁性粉末にSiO2、Al2O3、Ni3Fe、Cu、Niから選
ばれる少なくとも１種からなる被膜を設け、次い
でこの被膜を形成した金属磁性粉末の粒子表面を
一旦酸化した後、キレート化剤で処理してその粒
子表面にキレート化剤を存在させると、粒子表面
の酸化がさらに一段と良好に防止されて、一段と
酸化安定性に優れた金属磁性粉末が得られること
を見いだしてなされたもので、金属磁性粉末に
SiO2、Al2O3、Ni3Fe、Cu、Niから選ばれる少な
くとも１種からなる被膜を設け、次いでこれをそ
のまま、あるいは酸化した後、キレート化剤で処
理してその粒子表面にキレート化剤を存在させた
ものである。
この発明において、金属磁性粉末粒子表面への
SiO2、Al2O3、Ni3Fe、Cu、Niから選ばれる少な
くとも１種からなる被膜の形成は、たとえば、
SiO2からなる被膜の場合、オルトケイ酸ナトリ
ウム、メタケイ酸ナトリウム、メタケイ酸カリウ
ムおよび種々の組成の水ガラスなどの水溶性ケイ
酸塩をアルカリ水溶液中に溶解させ、この溶液中
にオキシ水酸化鉄粉末または酸化鉄粉末を分散さ
せた後、炭酸ガスを吹き込むか酸を添加するなど
の方法で中和して、オキシ水酸化鉄粉末または酸
化鉄粉末の粒子表面にケイ酸水和物として被着さ
せ、次いで、これを水素ガスなどの還元ガス雰囲
気中で300〜600℃の温度で加熱還元して金属鉄磁
性粉末を製造すると同時に形成される。この他、
このSiO2からなる被膜は、前記のようにケイ酸
水和物を被着していないオキシ水酸化鉄粉末また
は酸化鉄粉末を加熱還元して得た金属鉄磁性粉末
等の金属磁性粉末を、前記の水溶性ケイ酸塩をア
ルカリ水溶液中に溶解させて得られた溶液中に分
散させ、次いで、炭酸ガスを吹き込むか酸を添加
するなどして中和し、ケイ酸水和物として金属磁
性粉末の粒子表面に被着させた後、これを100℃
以上の温度で加熱処理することによつても形成さ
れる。このように、SiO2からなる被膜が金属磁
性粉末の粒子表面に形成されると、この種の
SiO2からなる被膜は酸化安定性に優れるため金
属磁性粉末の酸化安定性が向上し、特に還元前に
ケイ酸水和物が被着された場合は、加熱還元時の
焼結も良好に防止される。このようなSiO2から
なる被膜の被着量は、Si／金属磁性粉末の原子換
算重量比で0.1〜10重量％の範囲内にするのが好
ましく、少なすぎると金属磁性粉末の酸化安定性
が充分に向上されず、多すぎると非磁性成分が増
加し、磁化量の低下を起こす。
またAl2O3からなる被膜の場合は、硫酸アルミ
ニウム、硝酸アルミニウム、塩化アルミニウムな
どの水溶性アルミニウム塩、アルミン酸ナトリウ
ムなどの水溶性アルミン酸塩などのアルミニウム
化合物を、アルカリ水溶液中に溶解させ、この溶
液中にオキシ水酸化鉄粉末または酸化鉄粉末を分
散させた後、炭酸ガスを吹き込むか酸を添加する
などの方法で中和して、含水酸化アルミニウムと
してオキシ水酸化鉄粉末または酸化鉄粉末の粒子
表面に被着させ、次いで、これを水素ガスなどの
還元ガス雰囲気中で300〜600℃の温度で加熱還元
して金属鉄磁性粉末を製造すると同時に形成され
る。この他、前記のように含水酸化アルミニウム
を被着していないオキシ水酸化鉄粉末または酸化
鉄粉末を加熱還元して得た金属鉄磁性粉末等の金
属磁性粉末を、前記の水溶性アルミニウム化合物
をアルカリ水溶液中に溶解させて得られた溶液中
に分散させ、次いで、炭酸ガスを吹き込むか酸を
添加するなどして中和し、含水酸化アルミニウム
として金属磁性粉末の粒子表面に被着させた後、
これを100℃以上の温度で加熱処理することによ
つても形成される。このようにAl2O3からなる被
膜が金属磁性粉末の粒子表面に形成されると、こ
の種のAl2O3からなる被膜は酸化安定性に優れる
ため金属磁性粉末の酸化安定性が向上し、特に還
元前に含水酸化アルミニウムが被着された場合
は、加熱還元時の焼結も良好に防止される。この
ようなAl2O3からなる被膜の被着量は、Al／金属
磁性粉末の原子換算重量比で0.01〜５重量％の範
囲内にするのが好ましく、少なすぎると金属磁性
粉末の酸化安定性が充分に向上されず、多すぎる
と飽和磁化量の低下を招く。
このようにして、金属磁性粉末の粒子表面に
SiO2またはAl2O3からなる被膜が形成されるが、
金属磁性粉末の粒子表面に形成される被膜は、こ
れらSiO2またはAl2O3からなる被膜に限らず、
SiO2とAl2O3とが混合して形成された被膜であつ
てもよく、このSiO2とAl2O3とからなる被膜は、
オキシ水酸化鉄粉末又は酸化鉄粉末、もしくは金
属磁性粉末を、水溶性ケイ酸塩と水溶性アルミニ
ウム化合物とを混合して溶解したアルカリ水溶液
中に分散させて、前記と同様な処理を行うことに
よつて形成される。
さらに、Ni3Feからなる被膜の場合は、硫酸ニ
ツケル、硝酸ニツケル、塩化ニツケルなどの水溶
性ニツケル塩と、硫酸鉄、硝酸鉄、塩化鉄などの
水溶性鉄塩とを混合した混合液を、オキシ水酸化
鉄粉末または酸化鉄粉末のアルカリ性懸濁液中に
徐々に添加して水酸化第一鉄と水酸化第一ニツケ
ルの共沈物として被着し、次いで、これを水素ガ
スなどの還元ガス雰囲気中で300〜600℃の温度で
加熱還元して金属鉄磁性粉末を製造すると同時に
形成される。この他、前記のように水酸化第一鉄
と水酸化第一ニツケルを被着していないオキシ水
酸化鉄粉末または酸化鉄粉末を加熱還元して得た
金属鉄磁性粉末等の金属磁性粉末のアルカリ性懸
濁液中に、前記の水溶性ニツケル塩と水溶性鉄塩
とを混合した混合液を、徐々に添加して水酸化第
一鉄と水酸化第一ニツケルの共沈物として金属磁
性粉末の粒子表面に被着させ、これを200℃以上
の温度で加熱処理することによつても形成され
る。このようにNi3Feからなる被膜が金属磁性粉
末の粒子表面に形成されると、この種のNi3Feか
らなる被膜は酸化安定性に優れるため金属磁性粉
末の酸化安定性が向上する。このようなNi3Feか
らなる被膜の被着量は、Ni3Fe／金属磁性粉末の
原子換算重量比で１〜50重量％の範囲内にするの
が好ましく、少なすぎると金属磁性粉末の酸化安
定性が充分に向上されず、多すぎると粒子の針状
形態を損ない、飽和磁化量、角型の低下を招く。
また、Cuからなる被膜の場合は、硫酸銅、硝
酸銅、炭酸銅、ハロゲン化銅などの水溶性の銅塩
を、オキシ水酸化鉄粉末または酸化鉄粉末のアル
カリ性懸濁液中に徐々に添加して水酸化第一銅と
して被着し、次いで、これを水素ガスなどの還元
ガス雰囲気中で300〜600℃の温度で加熱還元して
金属鉄磁性粉末を製造すると同時に形成される。
この他、前記のように水酸化第一銅を被着してい
ないオキシ水酸化鉄粉末または酸化鉄粉末を加熱
還元して得た金属鉄磁性粉末等の金属磁性粉末
と、前記の水溶性の銅塩とを含むアルカリ性懸濁
液を還元剤で溶液中で還元させるなどの方法でも
形成される。このようにCuからなる被膜が金属
磁性粉末の粒子表面に形成されると、この種の
Cuからなる被膜は酸化安定性に優れるため金属
磁性粉末の硫化安定性が向上する。このような
Cuからなる被膜の被着量は、Cu／金属磁性粉末
の原子換算重量比で0.1〜10重量％の範囲内にす
るのが好ましく、少なすぎると金属磁性粉末の酸
化安定性が充分に向上されず、多すぎると磁化量
の低下を招く。
さらに、Niからなる被膜の場合は、硫酸ニツ
ケル、硝酸ニツケル、塩化ニツケルなどの水溶性
ニツケル塩を、オキシ水酸化鉄粉末または酸化鉄
粉末のアルカリ性懸濁液中に徐々に添加して水酸
化第一ニツケルとして被着し、次いで、これを水
素ガスなどの還元ガス雰囲気中で300〜600℃の温
度で加熱還元して金属鉄磁性粉末を製造すると同
時に形成される。この他、前記のように水酸化第
一ニツケルを被着していないオキシ水酸化鉄粉末
または酸化鉄粉末を加熱還元して得た金属鉄磁性
粉末等の金属磁性粉末のアルカリ性懸濁液中に、
前記の水溶性ニツケル塩の水溶液を、徐々に添加
して水酸化第一ニツケルを金属磁性粉末の粒子表
面に被着させ、これを200℃以上の温度で加熱処
理することによつても形成される。このように
Niからなる被膜が金属磁性粉末の粒子表面に形
成されると、この種のNiからなる被膜は酸化安
定性に優れるため金属磁性粉末の酸化安定性が向
上する。このようなNiからなる被膜の被着量は、
Ni／金属磁性粉末の原子換算重量比で１〜50重
量％の範囲内にするのが好ましく、少なすぎると
金属磁性粉末の酸化安定性が充分に向上されず、
多すぎると飽和磁化量、角型の低下を招き、また
針状形態を損なう。
このようにして、金属磁性粉末の粒子表面に、
Ni3FeまたはCuあるいはNiからなる被膜が形成
されるが、金属磁性粉末の粒子表面に形成される
被膜は、これらNi3FeまたはCuあるいはNiから
なる被膜に限らずに、これらが混合して形成され
た被膜であつてもよく、これらの混合した被膜
は、水溶性ニツケル塩、水溶性鉄塩、水溶性銅塩
等を混合して溶解した水溶液を、オキシ水酸化鉄
粉末または酸化鉄粉末、もしくは金属磁性粉末の
アルカリ懸濁液中に徐々に添加して、前記と同様
な処理を行うなどして形成される。
また、この発明において使用されるキレート化
剤は、２以上の多座配位子が配位したキレート団
またはキレート環をもつ化合物で、金属イオンと
良好に結合する。従つて、このキレート化剤で前
記のSiO2、Al2O3、Ni3Fe、Cu、Niから選ばれる
少なくとも１種からなる被膜を形成した金属磁性
粉末を処理すると、キレート化剤がこれらの
SiO2、Al2O3、Ni3Fe、Cu、Niから選ばれる少な
くとも１種からなる被膜の間から表面に露出した
金属磁性粉末粒子表面の金属イオンとキレート結
合して粒子表面に強固に被着され、SiO2、
Al2O3、Ni3Fe、Cu、Niから選ばれる少なくとも
１種からなる被膜を形成した金属磁性粉末の粒子
表面はさらに強固に結合したキレート化剤の疎水
部で被覆される。その結果、このSiO2、Al2O3、
Ni3Fe、Cu、Niから選ばれる少なくとも１種か
らなる被膜とキレート化剤によつて金属磁性粉末
の磁化量を減少させることなく、酸化防止効果が
充分に発揮され、酸化安定性に優れた金属磁性粉
末が得られる。そして、さらにSiO2、Al2O3、
Ni3Fe、Cu、Niから選ばれる少なくとも１種か
らなる被膜を形成した金属磁性粉末の粒子表面を
一旦酸化した後、キレート化剤で処理すると
SiO2、Al2O3、Ni3Fe、Cu、Niから選ばれる少な
くとも１種からなる被膜の間から表面に露出する
金属磁性粉末粒子表面の金属イオンが多量となり
キレート化剤が一段と良好に被着されるととも
に、酸化される余地が少なくなるため、キレート
化剤による酸化防止効果が一段と良好になり、一
段と酸化安定性に優れた金属磁性粉末が得られ
る。
このようなキレート化剤としては、通常キレー
ト化剤として使用されるものがいずれも使用さ
れ、たとえば、下記のものが好ましく使用され
る。
一般式
[Industrial Field of Application] The present invention relates to a metal magnetic powder suitable for use in magnetic recording media, and more particularly to the above-mentioned metal magnetic powder having excellent oxidation stability. [Prior art] Metal magnetic powders such as iron, nickel, and cobalt have superior magnetic properties compared to conventional oxide-based magnetic powders, but on the other hand, the surface of the powder particles is very active, so they cannot be used in the air. It is highly susceptible to oxidation, lacks oxidation stability, and has the disadvantage that the amount of saturation magnetization decreases over time. In order to improve these drawbacks, conventional methods have been to oxidize the particle surface of metal magnetic powder to form an oxide film (Japanese Patent Publication No. 56-28961), or to use higher aliphatic acids, carboxylic acids, metal soaps, and sulfonates. acid,
These coatings are formed by treatment with organic anticorrosive agents such as amines, phosphate esters, and esters (Special Publication Act 1983-
The oxidation stability has been improved by methods such as Japanese Patent No. 54485). [Problems to be solved by the invention] However, in the method of achieving oxidation stability by oxidizing the particle surface of metal magnetic powder, in order to ensure sufficient oxidation stability, it is necessary to increase the thickness of the oxide film on the particle surface. Therefore, the amount of magnetization of the magnetic powder decreases, and the decrease in the amount of magnetization due to surface oxidation is particularly significant as the magnetic powder becomes finer, and the high amount of magnetization that is characteristic of fine metal magnetic powder is maintained. The problem is that it cannot be done. In addition, in the method of treating the particle surface of metal magnetic powder with an organic anticorrosive agent,
Since the bonding force of these organic anticorrosive agents with metal ions is not so strong, sufficient anticorrosion effects are not exhibited, and sufficient oxidation stability has not yet been obtained. [Means for Solving the Problems] In view of the current situation, the present invention has been made based on various studies, and as a result, metal magnetic powder contains SiO 2 , Al 2 O 3 , Ni 3 Fe,
If a film made of at least one selected from Cu and Ni is provided and then treated with a chelating agent so that the chelating agent is present on the particle surface, attack by oxygen gas etc. is strongly prevented and oxidation is achieved. A metal magnetic powder with excellent stability was obtained, and the metal magnetic powder was further provided with a coating consisting of at least one selected from SiO 2 , Al 2 O 3 , Ni 3 Fe, Cu, and Ni, and then this coating was formed. If the particle surface of the metal magnetic powder is once oxidized and then treated with a chelating agent so that the chelating agent is present on the particle surface, oxidation of the particle surface is even better prevented, resulting in even better oxidation stability. It was created based on the discovery that it was possible to obtain metal magnetic powder with
A coating consisting of at least one selected from SiO 2 , Al 2 O 3 , Ni 3 Fe, Cu, and Ni is provided, and then this is treated as is or after oxidation, and then treated with a chelating agent to form a chelate on the particle surface. The agent is present. In this invention, the surface of the metal magnetic powder particles is
For example, the formation of a film made of at least one selected from SiO 2 , Al 2 O 3 , Ni 3 Fe, Cu, and Ni can be performed by:
In the case of coatings made of SiO 2 , water-soluble silicates such as sodium orthosilicate, sodium metasilicate, potassium metasilicate and water glass of various compositions are dissolved in an aqueous alkaline solution, and iron oxyhydroxide powder is added to this solution. Alternatively, after dispersing iron oxide powder, neutralize it by blowing carbon dioxide gas or adding acid, and deposit it as silicate hydrate on the particle surface of iron oxyhydroxide powder or iron oxide powder. Then, this is heated and reduced at a temperature of 300 to 600° C. in an atmosphere of a reducing gas such as hydrogen gas to produce metallic iron magnetic powder. In addition,
This film made of SiO 2 is made of a metal magnetic powder such as a metal iron magnetic powder obtained by heating and reducing iron oxyhydroxide powder or iron oxide powder that is not coated with silicic acid hydrate as described above. The above-mentioned water-soluble silicate is dissolved in an aqueous alkaline solution and dispersed in the resulting solution, and then neutralized by blowing carbon dioxide gas or adding acid to produce metal magnetic silicic acid hydrate. After coating the powder particle surface, heat it to 100℃.
It can also be formed by heat treatment at a temperature above. In this way, when a film made of SiO 2 is formed on the particle surface of metal magnetic powder, this kind of
The film made of SiO 2 has excellent oxidation stability, which improves the oxidation stability of metal magnetic powder, and also effectively prevents sintering during thermal reduction, especially if silicic acid hydrate is deposited before reduction. be done. It is preferable that the coating amount of SiO 2 be within the range of 0.1 to 10% by weight in terms of Si/metallic magnetic powder atomic weight ratio; if it is too small, the oxidation stability of the metallic magnetic powder may deteriorate. If the amount is too large without being sufficiently improved, the non-magnetic component will increase and the amount of magnetization will decrease. In the case of a film made of Al 2 O 3 , an aluminum compound such as a water-soluble aluminum salt such as aluminum sulfate, aluminum nitrate, or aluminum chloride, or a water-soluble aluminate such as sodium aluminate is dissolved in an alkaline aqueous solution. After dispersing iron oxyhydroxide powder or iron oxide powder in this solution, the iron oxyhydroxide powder or iron oxide powder is neutralized by blowing carbon dioxide gas or adding acid to form hydrated aluminum oxide powder. It is deposited on the surface of the particles, and then heated and reduced at a temperature of 300 to 600°C in an atmosphere of a reducing gas such as hydrogen gas to produce metal iron magnetic powder. In addition, metallic magnetic powder such as metallic iron magnetic powder obtained by heat reduction of iron oxyhydroxide powder or iron oxide powder that is not coated with hydrous aluminum oxide as described above can be used with the water-soluble aluminum compound described above. Dissolved in an alkaline aqueous solution and dispersed in the resulting solution, then neutralized by blowing carbon dioxide gas or adding acid, and deposited on the particle surface of metal magnetic powder as hydrous aluminum oxide. ,
It can also be formed by heat treating this at a temperature of 100°C or higher. When a film made of Al 2 O 3 is formed on the particle surface of the metal magnetic powder in this way, the oxidation stability of the metal magnetic powder is improved because this kind of film made of Al 2 O 3 has excellent oxidation stability. In particular, when hydrated aluminum oxide is deposited before reduction, sintering during thermal reduction is also well prevented. The coating amount of Al 2 O 3 is preferably within the range of 0.01 to 5% by weight in terms of the atomic weight ratio of Al/metallic magnetic powder; if it is too small, the oxidation stability of the metallic magnetic powder may deteriorate. If the amount is too high, the saturation magnetization level will be lowered. In this way, on the particle surface of metal magnetic powder,
A film consisting of SiO 2 or Al 2 O 3 is formed,
The coatings formed on the particle surfaces of metal magnetic powders are not limited to these SiO 2 or Al 2 O 3 coatings.
It may be a film formed by mixing SiO 2 and Al 2 O 3 , and this film made of SiO 2 and Al 2 O 3 is
Iron oxyhydroxide powder, iron oxide powder, or metal magnetic powder is dispersed in an alkaline aqueous solution in which a water-soluble silicate and a water-soluble aluminum compound are mixed and dissolved, and the same treatment as above is performed. It is formed as a result. Furthermore, in the case of a film made of Ni 3 Fe, a mixed solution of water-soluble nickel salts such as nickel sulfate, nickel nitrate, and nickel chloride, and water-soluble iron salts such as iron sulfate, iron nitrate, and iron chloride, is used. It is gradually added to an alkaline suspension of iron oxyhydroxide powder or iron oxide powder to form a coprecipitate of ferrous hydroxide and nickel hydroxide, which is then reduced with hydrogen gas, etc. It is formed at the same time as producing metallic iron magnetic powder by thermal reduction at a temperature of 300 to 600°C in a gas atmosphere. In addition, metallic magnetic powders such as metallic iron magnetic powders obtained by heating and reducing iron oxyhydroxide powders or iron oxide powders that are not coated with ferrous hydroxide and nickel hydroxide as described above are also available. A mixture of the above-mentioned water-soluble nickel salt and water-soluble iron salt is gradually added to the alkaline suspension to form a metal magnetic powder as a coprecipitate of ferrous hydroxide and nickel hydroxide. It can also be formed by adhering it to the surface of particles and heat-treating it at a temperature of 200°C or higher. When a coating made of Ni 3 Fe is formed on the particle surface of the metal magnetic powder in this way, the oxidation stability of the metal magnetic powder is improved because this kind of coating made of Ni 3 Fe has excellent oxidation stability. The coating amount of Ni 3 Fe is preferably within the range of 1 to 50% by weight in terms of Ni 3 Fe/metallic magnetic powder atomic weight ratio; if it is too small, the metal magnetic powder may be oxidized. The stability is not sufficiently improved, and if the amount is too large, the acicular morphology of the particles is impaired, resulting in a decrease in saturation magnetization and squareness. In addition, in the case of a film made of Cu, water-soluble copper salts such as copper sulfate, copper nitrate, copper carbonate, copper halide, etc. are gradually added to an alkaline suspension of iron oxyhydroxide powder or iron oxide powder. This is deposited as cuprous hydroxide, which is then heated and reduced at a temperature of 300 to 600°C in an atmosphere of a reducing gas such as hydrogen gas to produce metallic iron magnetic powder.
In addition, metallic magnetic powders such as metallic iron magnetic powders obtained by heat reduction of iron oxyhydroxide powders or iron oxide powders which are not coated with cuprous hydroxide as mentioned above, and the above-mentioned water-soluble It can also be formed by reducing an alkaline suspension containing a copper salt in solution using a reducing agent. When a film made of Cu is formed on the surface of metal magnetic powder particles, this kind of
The coating made of Cu has excellent oxidation stability, which improves the sulfidation stability of the metal magnetic powder. like this
The coating amount of Cu is preferably within the range of 0.1 to 10% by weight in terms of Cu/metal magnetic powder atomic weight ratio; if it is too small, the oxidation stability of the metal magnetic powder may not be sufficiently improved. On the other hand, if it is too large, the amount of magnetization will decrease. Furthermore, in the case of a coating made of Ni, water-soluble nickel salts such as nickel sulfate, nickel nitrate, and nickel chloride are gradually added to an alkaline suspension of iron oxyhydroxide powder or iron oxide powder to make hydroxide. It is formed at the same time as metal iron magnetic powder is produced by depositing it as one nickel and then reducing it by heating at a temperature of 300 to 600° C. in a reducing gas atmosphere such as hydrogen gas. In addition, as mentioned above, in an alkaline suspension of metal magnetic powder such as metal iron magnetic powder obtained by heating reduction of iron oxyhydroxide powder or iron oxide powder that is not coated with nickel hydroxide, ,
It can also be formed by gradually adding an aqueous solution of the above-mentioned water-soluble nickel salt to deposit nickel hydroxide on the surface of the particles of metal magnetic powder, and then heat-treating this at a temperature of 200°C or higher. Ru. in this way
When a coating made of Ni is formed on the particle surface of a metal magnetic powder, the oxidation stability of the metal magnetic powder is improved because this type of coating made of Ni has excellent oxidation stability. The amount of coating made of Ni is:
The atomic weight ratio of Ni/metal magnetic powder is preferably within the range of 1 to 50% by weight; if it is too small, the oxidation stability of the metal magnetic powder will not be sufficiently improved;
If it is too large, the amount of saturation magnetization and the square shape will be reduced, and the acicular shape will be impaired. In this way, on the particle surface of metal magnetic powder,
A film made of Ni 3 Fe, Cu, or Ni is formed, but the film formed on the particle surface of metal magnetic powder is not limited to a film made of Ni 3 Fe, Cu, or Ni, but may be a mixture of these. The mixed coating may be formed by mixing an aqueous solution of water-soluble nickel salt, water-soluble iron salt, water-soluble copper salt, etc. with iron oxyhydroxide powder or iron oxide powder. Alternatively, it can be formed by gradually adding metal magnetic powder to an alkaline suspension and performing the same treatment as described above. Further, the chelating agent used in the present invention is a compound having a chelate group or a chelate ring in which two or more polydentate ligands are coordinated, and binds well to metal ions. Therefore, when this chelating agent is used to treat the metal magnetic powder that has formed a coating consisting of at least one selected from SiO 2 , Al 2 O 3 , Ni 3 Fe, Cu, and Ni, the chelating agent will cause the formation of these particles.
It forms a chelate bond with the metal ions on the surface of the metal magnetic powder particles exposed between the coatings made of at least one selected from SiO 2 , Al 2 O 3 , Ni 3 Fe, Cu, and Ni, and forms a strong coating on the particle surface. SiO 2 ,
The particle surface of the metal magnetic powder, on which a film formed of at least one selected from Al 2 O 3 , Ni 3 Fe, Cu, and Ni is formed, is further coated with a strongly bonded hydrophobic portion of a chelating agent. As a result, this SiO 2 , Al 2 O 3 ,
The coating consisting of at least one member selected from Ni 3 Fe, Cu, and Ni and the chelating agent provide sufficient oxidation prevention effect without reducing the amount of magnetization of the metal magnetic powder, and have excellent oxidation stability. Metal magnetic powder is obtained. Furthermore, SiO 2 , Al 2 O 3 ,
When the particle surface of metal magnetic powder on which a coating consisting of at least one selected from Ni 3 Fe, Cu, and Ni is formed is once oxidized and then treated with a chelating agent.
A large amount of metal ions on the surface of the metal magnetic powder particles are exposed between the coatings made of at least one selected from SiO 2 , Al 2 O 3 , Ni 3 Fe, Cu, and Ni, and the chelating agent is more effectively covered. At the same time, there is less room for oxidation, so the oxidation-preventing effect of the chelating agent becomes even better, and a metal magnetic powder with even better oxidation stability can be obtained. As such a chelating agent, any of those commonly used as a chelating agent can be used, and for example, the following are preferably used. general formula
【化】
（但し、式中R1およびR2は炭素原子数が１〜24
のアルキル基またはアリール基、R3はＨまたは
R1と同一である。）
で示されるカルボニル基間に少なくとも１つのメ
チレン水素を有するβ−ジケトン、たとえば、ア
セチルアセトン、メチルアセチルアセトン、エチ
ルアセチルアセトン、プロピルアセチルアセト
ン、フエニルアセチルアセトン、プロピオニルア
セトン、ジプロピオニルメタン、ベンゾイルアセ
トン、ジベンゾイルメタン、メチルベンゾイルア
セトン、メチルジベンゾイルメタン等
一般式[Chemical formula] (However, in the formula, R 1 and R 2 have 1 to 24 carbon atoms.
alkyl group or aryl group, R 3 is H or
Same as R 1 . ) β-diketones having at least one methylene hydrogen between carbonyl groups, such as acetylacetone, methylacetylacetone, ethylacetylacetone, propylacetylacetone, phenylacetylacetone, propionylacetone, dipropionylmethane, benzoylacetone, dibenzoylmethane, Methylbenzoylacetone, methyldibenzoylmethane, etc. General formula
【化】
（但し、式中R1およびR2は炭素原子数が１〜24
のアルキル基またはアリール基、R3はＨまたは
R1と同一である。）
で示されるケトおよびカルボキシル基間に少なく
とも１つのメチレン水素を有するβ−ケトカルボ
ン酸エステル、たとえば、アセト酢酸メチルエス
テル、アセト酢酸エチルエステル、アセト酢酸プ
ロピルエステル、アセト酢酸イソプロピルエステ
ル、アセト酢酸ブチルエステル、アセト酢酸イソ
ブチルエステル、アセト酢酸−ｔ−ブチルエステ
ル、アセト酢酸アミルエステル、アセト酢酸ヘキ
シルエステル、アセト酢酸ノニルエステル、アセ
ト酢酸デシルエステル等
芳香族ｏ−オキシケトン、たとえば、ｏ−オキ
シアセトフエノン
ｏ−オキシアルデヒド、たとえば、サリチルア
ルデヒド
上記のカルボニル化合物とアミンとのシツフ塩
基、たとえば、アセチルアセトアニル、ビスアセ
チルアセトンエチレンジアミン、ビス−サリチル
アルデヒドエチレンジアミン、ビス−サリチルア
ルデヒド−ｏ−フエニレンジアミン、ビス−サリ
チルアルデヒドプロピレンジアミン、ビス−アセ
チルアセトン−ｏ−フエニレンジアミン
一般基[Chemical formula] (However, in the formula, R 1 and R 2 have 1 to 24 carbon atoms.
alkyl group or aryl group, R 3 is H or
Same as R 1 . ) β-ketocarboxylic acid esters having at least one methylene hydrogen between the keto and carboxyl groups, such as methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, isopropyl acetoacetate, butyl acetoacetate, Isobutyl acetoacetate, t-butyl acetoacetate, amyl acetoacetate, hexyl acetoacetate, nonyl acetoacetate, decyl acetoacetate, etc. Aromatic o-oxyketones, such as o-oxyacetophenone o-oxy Aldehydes, e.g. salicylaldehyde Schiff bases of the above carbonyl compounds with amines, e.g. acetylacetanyl, bisacetylacetone ethylenediamine, bis-salicylaldehyde ethylenediamine, bis-salicylaldehyde-o-phenylenediamine, bis-salicylaldehyde propylenediamine , bis-acetylacetone-o-phenylenediamine general group
【式】または[expression] or
【式】
（但し、ｎは１または２の整数である。）
を有するアミノ酢酸またはアミノプロピオン酸、
たとえば、エチレンジアミンテトラ酢酸、エチレ
ンジアミンテトラプロピオン酸、ニトリロトリ酢
酸、イミノジ酢酸、イミノジプロピオン酸、メラ
ミンヘキサ酢酸、メラミンヘキサプロピオン酸ま
たはそのアルカリ塩
一般基[Formula] (However, n is an integer of 1 or 2.) Aminoacetic acid or aminopropionic acid,
For example, ethylenediaminetetraacetic acid, ethylenediaminetetrapropionic acid, nitrilotriacetic acid, iminodiacetic acid, iminodipropionic acid, melamine hexaacetic acid, melamine hexapropionic acid or its alkali salt General group
【式】または[expression] or
【式】もしくは[Formula] or
次に、この発明の実施例について説明する。
実施例 １
２モル／の苛性ソーダ水溶液２中に0.5モ
ル／の硫酸第一鉄水溶液１を加えて反応さ
せ、水酸化第一鉄の緑色を帯びた乳白色の沈澱物
を得た。次いで、この沈澱物懸濁液を60℃に保ち
ながら５／分の速度で空気を吹き込んで６時間
撹拌してα−オキシ水酸化鉄の懸濁液を得た。
次に、この強アルカリ性のα−オキシ水酸化鉄
懸濁液中に、１モル／のオルトケイ酸ソーダ水
溶液70mlを添加混合し、これに炭酸ガスを吹き込
み、PH10以下に中和してα−オキシ水酸化鉄粉末
の粒子表面にケイ酸水和物を被着させた。その
後、水洗、乾燥を行つた後、電気炉を用いて700
℃で２時間加熱、脱水を行い、α−酸化鉄に変性
させた。
次いで、ケイ酸水和物で被覆されたα−酸化鉄
を還元炉に充填し、水素ガスを流速１／分で通
気して、500℃の温度で５時間加熱還元し、SiO2
で被覆された針状微粒子金属鉄磁性粉末を得た。
このSiO2で被覆された針状微粒子金属鉄磁性粉
末は、長径0.3μ、軸比（長径／短径）15／１、保
磁力1500エルステツドで、飽和磁化量は
150emu／ｇであつた。
このようにして得られたSiO2で被覆された針
状微粒子金属鉄磁性粉末10ｇを、ガラスチユーブ
で連結されたフラスコに入れ、真空ポンプで脱気
した。次いで、徐々に空気を送り込み、SiO2で
被覆された針状微粒子金属鉄磁性粉末の粒子表面
を酸化した。しかる後、別のフラスコに入れられ
たアセチルアセトンの飽和蒸気を徐々に導入し、
粒子表面に吸着させてアセチルアセトンで表面処
理され、かつSiO2で被覆された針状微粒子金属
鉄磁性粉末を得た。
実施例 ２〜12
実施例１におけるキレート化処理において、ア
セチルアセトンの飽和蒸気に代えて、下記第１表
に示す各キレート化剤の飽和蒸気を使用した以外
は実施例１と同様にして、各キレート化剤で表面
処理され、かつSiO2で被覆された針状微粒子金
属鉄磁性粉末を得た。
Next, embodiments of the invention will be described. Example 1 A 0.5 mol/mol ferrous sulfate aqueous solution 1 was added to a 2 mol/mol caustic soda aqueous solution 2 and reacted to obtain a greenish, milky white precipitate of ferrous hydroxide. Next, while maintaining the precipitate suspension at 60°C, air was blown at a rate of 5/min and stirred for 6 hours to obtain a suspension of α-iron oxyhydroxide. Next, 70 ml of a 1 mol/mol sodium orthosilicate aqueous solution was added and mixed into this strongly alkaline alpha-oxyiron hydroxide suspension, and carbon dioxide was blown into this to neutralize the pH to below 10. Silicic acid hydrate was deposited on the surface of iron hydroxide powder particles. After that, after washing with water and drying, 700
The mixture was heated at ℃ for 2 hours, dehydrated, and denatured into α-iron oxide. Next, the α-iron oxide coated with silicic acid hydrate was charged into a reduction furnace, hydrogen gas was passed through it at a flow rate of 1/min, and the mixture was heated and reduced at a temperature of 500°C for 5 hours to form SiO 2
Acicular fine particle metallic iron magnetic powder coated with
This acicular fine metal iron magnetic powder coated with SiO 2 has a major axis of 0.3μ, an axial ratio (major axis/minor axis) of 15/1, a coercive force of 1500 oersteds, and a saturation magnetization amount of
It was 150 emu/g. 10 g of the SiO 2 -coated acicular fine metal iron magnetic powder thus obtained was placed in a flask connected with a glass tube and degassed using a vacuum pump. Next, air was gradually introduced to oxidize the particle surface of the acicular fine metal iron magnetic powder coated with SiO 2 . Afterwards, gradually introduce saturated vapor of acetylacetone in another flask,
Acicular fine particle metallic iron magnetic powder was adsorbed onto the particle surface, surface-treated with acetylacetone, and coated with SiO 2 . Examples 2 to 12 In the chelation treatment in Example 1, each chelate was treated in the same manner as in Example 1, except that saturated vapor of each chelating agent shown in Table 1 below was used instead of saturated vapor of acetylacetone. Acicular fine particle metallic iron magnetic powder whose surface was treated with a curing agent and coated with SiO 2 was obtained.
【表】【table】
【表】
実施例 13〜24
実施例１〜12のそれぞれにおいて、空気での酸
化を省いた以外はそれぞれ実施例１〜12と同様に
してそれぞれのキレート化剤で処理され、かつ
SiO2で被覆された針状微粒子金属鉄磁性粉末を
得た。
実施例 25〜36
実施例１と同様にしてα−オキシ水酸化鉄の懸
濁液を得、この強アルカリ性のα−オキシ水酸化
鉄懸濁液中に、0.1モル／の硫酸アルミニウム
水溶液20mlを添加混合し、これに炭酸ガスを吹き
込み、PH10以下に中和してα−オキシ水酸化鉄粉
末の粒子表面に含水酸化アルミニウムを被着させ
た。その後、水洗、乾燥を行つた後、電気炉を用
いて600℃で２時間加熱、脱水を行い、α−酸化
鉄に変性させた。
次いで、含水酸化アルミニウムで被覆されたα
−酸化鉄を還元炉に充填し、水素ガスを流速１
／分で通気して、450℃の温度で６時間加熱還
元し、Al2O3で被覆された針状微粒子金属鉄磁性
粉末を得た。このAl2O3で被覆された針状微粒子
金属鉄磁性粉末は、長径0.3μ、軸比（長径／短
径）15／１、保磁力1350エルステツドで、飽和磁
化量は160emu／ｇであつた。
このようにして得られたAl2O3で被覆された針
状微粒子金属鉄磁性粉末10ｇを、ガラスチユーブ
で連結されたフラスコに入れ、実施例１〜12と同
様にしてキレート化処理を行い、アセチルアセト
ンおよび前記第１表に示される各キレート化剤で
表面処理され、かつAl2O3で被覆された針状微粒
子金属鉄磁性粉末を得た。
実施例 37〜48
実施例25〜36のそれぞれにおいて、空気での酸
化を省いた以外はそれぞれ実施例25〜36と同様に
してそれぞれのキレート化剤で処理され、かつ
Al2O3で被覆された針状微粒子金属鉄磁性粉末を
得た。
実施例 49〜60
実施例１と同様にしてα−オキシ水酸化鉄の懸
濁液を得、この強アルカリ性のα−オキシ水酸化
鉄懸濁液中に、0.1モル／の硫酸第一ニツケル
水溶液250mlと0.1モル／の硫酸第一鉄水溶液50
mlとを混合した混合液を徐々に添加して、α−オ
キシ水酸化鉄粉末の粒子表面に水酸化第一ニツケ
ルと水酸化第一鉄の共沈物を被着させた。その
後、水洗、乾燥を行つた後、電気炉を用いて500
℃で２時間加熱、脱水を行い、α−酸化鉄に変性
させた。
次いで、水酸化第一ニツケルと水酸化第一鉄の
共沈物で被覆されたα−酸化鉄を還元炉に充填
し、水素ガスを流速１／分で通気して、400℃
の温度で６時間加熱還元し、Ni3Feで被覆された
針状微粒子金属鉄磁性粉末を得た。このNi3Feで
被覆された針状微粒子金属鉄磁性粉末は、長径
0.3μ、軸比（長径／短径）15／１、保磁力1250エ
ルステツドで、飽和磁化量は165emu／ｇであつ
た。
このようにして得られたNi3F6で被覆された針
状微粒子金属鉄磁性粉末10ｇを、ガラスチユーブ
で連結されたフラスコに入れ、実施例１〜12と同
様にしてキレート化処理を行い、アセチルアセト
ンおよび前記第１表に示される各キレート化剤で
表面処理され、かつNi3Feで被覆された針状微粒
子金属鉄磁性粉末を得た。
実施例 61〜72
実施例49〜60のそれぞれにおいて、空気での酸
化を省いた以外はそれぞれ実施例49〜60と同様に
してそれぞれのキレート化剤で処理され、かつ
Ni3Feで被覆された針状微粒子金属鉄磁性粉末を
得た。
実施例 73〜84
実施例１と同様にしてα−オキシ水酸化鉄の懸
濁液を得、この強アルカリ性のα−オキシ水酸化
鉄懸濁液中に、0.1モル／の硫酸銅水溶液20ml
を徐々に添加して、α−オキシ水酸化鉄粉末の粒
子表面に水酸化銅を被着させた。その後、水洗、
乾燥を行つた後、電気炉を用いて400℃で２時間
加熱、脱水を行い、α−酸化鉄に変性させた。
次いで、水酸化銅で被覆されたα−酸化鉄を還
元炉に充填し、水素ガスを流速１／分で通気し
て、450℃の温度で４時間加熱還元し、Cuで被覆
された針状微粒子金属鉄磁性粉末を得た。この
Cuで被覆された針状微粒子金属鉄磁性粉末は、
長径0.3μ、軸比（長径／短径）15／１、保磁力
1320エルステツドで、飽和磁化量は162emu／ｇ
であつた。
このようにして得られたCuで被覆された針状
微粒子金属鉄磁性粉末10ｇを、ガラスチユーブで
連結されたフラスコに入れ、実施例１〜12と同様
にしてキレート化処理を行い、アセチルアセトン
および前記第１表に示される各キレート化剤で表
面処理され、かつCuで被覆された針状微粒子金
属鉄磁性粉末を得た。
実施例 85〜96
実施例73〜84のそれぞれにおいて、空気での酸
化を省いた以外はそれぞれ実施例73〜84と同様に
してそれぞれのキレート化剤で処理され、かつ
Cuで被覆された針状微粒子金属鉄磁性粉末を得
た。
実施例 97〜108
実施例１と同様にしてα−オキシ水酸化鉄の懸
濁液を得、この強アルカリ性のα−オキシ水酸化
鉄懸濁液中に、0.1モル／の硫酸ニツケル水溶
液200mlを徐々に添加して、α−オキシ水酸化鉄
粉末の粒子表面に水酸化ニツケルを被着させた。
その後、水洗、乾燥を行つた後、電気炉を用いて
300℃で２時間加熱、脱水を行い、α−酸化鉄に
変性させた。
次いで、水酸化ニツケルで被覆されたα−酸化
鉄を還元炉に充填し、水素ガスを流速１／分で
通気して、450℃の温度で４時間加熱還元し、Ni
で被覆された針状微粒子金属鉄磁性粉末を得た。
このNiで被覆された針状微粒子金属鉄磁性粉末
は、長径0.3μ、軸比（長径／短径）15／１、保磁
力1150エルステツドで、飽和磁化量は164emu／
ｇであつた。
このようにして得られたNiで被覆された針状
微粒子金属鉄磁性粉末10ｇを、ガラスチユーブで
連結されたフラスコに入れ、実施例１〜12と同様
にしてキレート化処理を行い、アセチルアセトン
および前記第１表に示される各キレート化剤で表
面処理され、かつNiで被覆された針状微粒子金
属鉄磁性粉末を得た。
実施例 109〜120
実施例97〜108のそれぞれにおいて、空気での
酸化を省いた以外はそれぞれ実施例97〜108と同
様にしてそれぞれのキレート化剤で処理され、か
つNiで被覆された針状微粒子金属鉄磁性粉末を
得た。
比較例 １
実施例１において、ケイ酸水和物の被着処理お
よびキレート化処理を省いた以外は実施例１と同
様にして、針状微粒子金属鉄磁性粉末を得た。
比較例 ２
実施例１において、キレート化処理を省いた以
外は実施例１と同様にしてSiO2で被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 ３
実施例13において、キレート化処理を省いた以
外は実施例１と同様にしてSiO2で被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 ４
実施例１において、SiO2で被覆された針状微
粒子金属鉄磁性粉末のキレート化処理を省き、こ
のSiO2で被覆された針状微粒子金属鉄磁性粉末
５ｇを、トルエン300mlにラノリン酸カルシウム
500mgを溶解した溶液中に浸漬して30分間撹拌混
合した。しかる後、濾過し、室温下で乾燥してラ
ノリン酸カルシウムおよびSiO2によつて粒子表
面が被覆された針状微粒子金属鉄磁性粉末を得
た。
比較例 ５
実施例13において、SiO2で被覆された針状微
粒子金属鉄磁性粉末のキレート化処理を省き、こ
のSiO2で被覆された針状微粒子金属鉄磁性粉末
５ｇを、トルエン300mlにラノリン酸カルシウム
500mgを溶解した溶液中に浸漬して30分間撹拌混
合した。しかる後、濾過し、室温下で乾燥してラ
ノリン酸カルシウムおよびSiO2によつて粒子表
面が被覆された針状微粒子金属鉄磁性粉末を得
た。
比較例 ６
実施例25において、キレート化処理を省いた以
外は実施例25と同様にしてAl2O3で被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 ７
実施例37において、キレート化処理を省いた以
外は実施例37と同様にしてAl2O3で被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 ８
実施例25において、Al2O3で被覆された針状微
粒子金属鉄磁性粉末のキレート化処理を省き、こ
のAl2O3で被覆された針状微粒子金属鉄磁性粉末
５ｇを、トルエン300mlにラノリン酸カルシウム
500mgを溶解した溶液中に浸漬して30分間撹拌混
合した。しかる後、濾過し、室温下で乾燥してラ
ノリン酸カルシウムおよびAl2O3によつて粒子表
面が被覆された針状微粒子金属鉄磁性粉末を得
た。
比較例 ９
実施例37において、Al2O3で被覆された針状微
粒子金属鉄磁性粉末のキレート化処理を省き、こ
のAl2O3で被覆された針状微粒子金属鉄磁性粉末
５ｇを、トルエン300mlにラノリン酸カルシウム
500mgを溶解した溶液中に浸漬して30分間撹拌混
合した。しかる後、濾過し、室温下で乾燥してラ
ノリン酸カルシウムおよびAl2O3によつて粒子表
面が被覆された針状微粒子金属鉄磁性粉末を得
た。
比較例 10
実施例49において、キレート化処理を省いた以
外は実施例49と同様にしてNi3Feで被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 11
実施例61において、キレート化処理を省いた以
外は実施例61と同様にしてNi3Feで被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 12
実施例49において、Ni3Feで被覆された針状微
粒子金属鉄磁性粉末のキレート化処理を省き、こ
のNi3Feで被覆された針状微粒子金属鉄磁性粉末
５ｇを、トルエン300mlにラノリン酸カルシウム
500mgを溶解した溶液中に浸漬して30分間撹拌混
合した。しかる後、濾過し、室温下で乾燥してラ
ノリン酸カルシウムおよびNi3Feによつて粒子表
面が被覆された針状微粒子金属鉄磁性粉末を得
た。
比較例 13
実施例61において、Ni3Feで被覆された針状微
粒子金属鉄磁性粉末のキレート化処理を省き、こ
のNi3Feで被覆された針状微粒子金属鉄磁性粉末
５ｇを、トルエン300mlにラノリン酸カルシウム
500mgを溶解した溶液中に浸漬して30分間撹拌混
合した。しかる後、濾過し、室温下で乾燥してラ
ノリン酸カルシウムおよびNi3Feによつて粒子表
面が被覆された針状微粒子金属鉄磁性粉末を得
た。
比較例 14
実施例73において、キレート化処理を省いた以
外は実施例73と同様にしてCuで被覆された針状
微粒子金属鉄磁性粉末を得た。
比較例 15
実施例85において、キレート化処理を省いた以
外は実施例85と同様にしてCuで被覆された針状
微粒子金属鉄磁性粉末を得た。
比較例 16
実施例73において、Cuで被覆された針状微粒
子金属鉄磁性粉末のキレート化処理を省き、この
Cuで被覆された針状微粒子金属鉄磁性粉末５ｇ
を、トルエン300mlにラノリン酸カルシウム500mg
を溶解した溶液中に浸漬して30分間撹拌混合し
た。しかる後、濾過し、室温下で乾燥してラノリ
ン酸カルシウムおよびCuによつて粒子表面が被
覆された針状微粒子金属鉄磁性粉末を得た。
比較例 17
実施例85において、Cuで被覆された針状微粒
子金属鉄磁性粉末のキレート化処理を省き、この
Cuで被覆された針状微粒子金属鉄磁性粉末５ｇ
を、トルエン300mlにラノリン酸カルシウム500mg
を溶解した溶液中に浸漬して30分間撹拌混合し
た。しかる後、濾過し、室温下で乾燥してラノリ
ン酸カルシウムおよびCuによつて粒子表面が被
覆された針状微粒子金属鉄磁性粉末を得た。
比較例 18
実施例97において、キレート化処理を省いた以
外は実施例97と同様にしてNiで被覆された針状
微粒子金属鉄磁性粉末を得た。
比較例 19
実施例109において、キレート化処理を省いた
以外は実施例109と同様にしてNiで被覆された針
状微粒子金属鉄磁性粉末を得た。
比較例 20
実施例97において、Niで被覆された針状微粒
子金属鉄磁性粉末のキレート化処理を省き、この
Niで被覆された針状微粒子金属鉄磁性粉末５ｇ
を、トルエン300mlにラノリン酸カルシウム500mg
を溶解した溶液中に浸漬して30分間撹拌混合し
た。しかる後、濾過し、室温下で乾燥してラノリ
ン酸カルシウムおよびNiによつて粒子表面が被
覆された針状微粒子金属鉄磁性粉末を得た。
比較例 21
実施例109において、Niで被覆された針状微粒
子金属鉄磁性粉末のキレート化処理を省き、この
Niで被覆された針状微粒子金属鉄磁性粉末５ｇ
を、トルエン300mlにラノリン酸カルシウム500mg
を溶解した溶液中に浸漬して30分間撹拌混合し
た。しかる後、濾過し、室温下で乾燥してラノリ
ン酸カルシウムおよびNiによつて粒子表面が被
覆された針状微粒子金属鉄磁性粉末を得た。
各実施例および各比較例で得られた針状微粒子
金属磁性粉末について、酸化安定性を試験した。
酸化安定性の試験は、示差熱分析計を用いて、各
針状微粒子金属鉄磁性粉末の空気中での酸化促進
温度（発火点）を測定して行つた。
下記第２表および第３表はその結果である。[Table] Examples 13 to 24 Each of Examples 1 to 12 was treated with the respective chelating agent in the same manner as in Examples 1 to 12, except that the oxidation in air was omitted, and
Acicular fine particle metallic iron magnetic powder coated with SiO 2 was obtained. Examples 25-36 A suspension of α-iron oxyhydroxide was obtained in the same manner as in Example 1, and 20 ml of a 0.1 mol/aqueous aluminum sulfate solution was added to this strongly alkaline α-iron oxyhydroxide suspension. The mixture was added and mixed, and carbon dioxide gas was blown into the mixture to neutralize the pH to below 10, thereby depositing hydrated aluminum oxide on the particle surface of the α-iron oxyhydroxide powder. Thereafter, after washing with water and drying, the material was heated at 600° C. for 2 hours using an electric furnace, dehydrated, and denatured into α-iron oxide. Then α coated with hydrous aluminum oxide
- Fill iron oxide into a reduction furnace and supply hydrogen gas at a flow rate of 1
The mixture was heated and reduced at a temperature of 450° C. for 6 hours while aerating at a rate of 100° C./min to obtain acicular fine metal iron magnetic powder coated with Al 2 O 3 . This acicular fine metal iron magnetic powder coated with Al 2 O 3 had a major axis of 0.3 μ, an axial ratio (major axis/minor axis) of 15/1, a coercive force of 1350 oersted, and a saturation magnetization of 160 emu/g. . 10 g of the acicular fine metal iron magnetic powder coated with Al 2 O 3 thus obtained was placed in a flask connected with a glass tube, and chelation treatment was performed in the same manner as in Examples 1 to 12. Acicular fine particle metallic iron magnetic powder was surface-treated with acetylacetone and each chelating agent shown in Table 1 and coated with Al 2 O 3 . Examples 37-48 Each of Examples 25-36 was treated with the respective chelating agent as in Examples 25-36, except that the air oxidation was omitted, and
Acicular fine particle metallic iron magnetic powder coated with Al 2 O 3 was obtained. Examples 49 to 60 A suspension of α-iron oxyhydroxide was obtained in the same manner as in Example 1, and in this strongly alkaline α-iron oxyhydroxide suspension, 0.1 mol/aqueous solution of nickel sulfate was added. 250ml and 0.1mol/ferrous sulfate aqueous solution 50
ml was gradually added to deposit a coprecipitate of nickel hydroxide and ferrous hydroxide on the particle surface of the α-iron oxyhydroxide powder. After that, after washing with water and drying, use an electric furnace to heat the
The mixture was heated at ℃ for 2 hours, dehydrated, and denatured into α-iron oxide. Next, α-iron oxide coated with a coprecipitate of nickel hydroxide and ferrous hydroxide was charged into a reduction furnace, hydrogen gas was bubbled in at a flow rate of 1/min, and the temperature was heated to 400°C.
The mixture was heated and reduced for 6 hours at a temperature of 100 mL to obtain acicular fine particle metallic iron magnetic powder coated with Ni 3 Fe. This Ni 3 Fe-coated acicular fine particle metal iron magnetic powder has a major diameter
It was 0.3μ, axial ratio (major axis/minor axis) 15/1, coercive force 1250 oersted, and saturation magnetization was 165 emu/g. 10 g of the Ni 3 F 6 coated acicular fine particle metallic iron magnetic powder thus obtained was placed in a flask connected with a glass tube, and chelation treatment was performed in the same manner as in Examples 1 to 12. Acicular fine particle metallic iron magnetic powder was surface-treated with acetylacetone and each chelating agent shown in Table 1 above and coated with Ni 3 Fe. Examples 61-72 Each of Examples 49-60 was treated with the respective chelating agent as in Examples 49-60, except that the air oxidation was omitted, and
Acicular fine particle metallic iron magnetic powder coated with Ni 3 Fe was obtained. Examples 73-84 A suspension of α-iron oxyhydroxide was obtained in the same manner as in Example 1, and 20 ml of a 0.1 mol/a copper sulfate aqueous solution was added to this strongly alkaline α-iron oxyhydroxide suspension.
was gradually added to deposit copper hydroxide on the particle surface of the α-iron oxyhydroxide powder. After that, wash with water,
After drying, it was heated at 400° C. for 2 hours using an electric furnace, dehydrated, and denatured into α-iron oxide. Next, α-iron oxide coated with copper hydroxide was charged into a reduction furnace, hydrogen gas was passed through it at a flow rate of 1/min, and heat-reduced at a temperature of 450°C for 4 hours to form a needle-like shape coated with Cu. Fine particle metallic iron magnetic powder was obtained. this
Acicular fine particle metallic iron magnetic powder coated with Cu is
Major axis 0.3μ, axial ratio (major axis/minor axis) 15/1, coercive force
1320 oersted, saturation magnetization is 162emu/g
It was hot. 10 g of the acicular fine metal iron magnetic powder coated with Cu thus obtained was placed in a flask connected with a glass tube, and chelation treatment was performed in the same manner as in Examples 1 to 12, and acetylacetone and the Acicular fine particle metallic iron magnetic powders were obtained which were surface treated with each of the chelating agents shown in Table 1 and coated with Cu. Examples 85-96 Each of Examples 73-84 was treated with the respective chelating agent as in Examples 73-84, except that the air oxidation was omitted, and
Acicular fine particle metallic iron magnetic powder coated with Cu was obtained. Examples 97 to 108 A suspension of α-iron oxyhydroxide was obtained in the same manner as in Example 1, and 200 ml of a 0.1 mol/aqueous nickel sulfate solution was added to this strongly alkaline α-iron oxyhydroxide suspension. Nickel hydroxide was gradually added to the surface of the α-iron oxyhydroxide powder particles.
After that, after washing with water and drying, use an electric furnace to
The mixture was heated at 300°C for 2 hours, dehydrated, and denatured into α-iron oxide. Next, the α-iron oxide coated with nickel hydroxide was charged into a reduction furnace, hydrogen gas was passed through it at a flow rate of 1/min, and the Ni was heated and reduced at a temperature of 450°C for 4 hours.
Acicular fine particle metallic iron magnetic powder coated with
This Ni-coated acicular fine particle metallic iron magnetic powder has a major axis of 0.3 μ, an axial ratio (major axis/minor axis) of 15/1, a coercive force of 1150 oersted, and a saturation magnetization of 164 emu/min.
It was hot at g. 10 g of the Ni-coated acicular fine particle metal iron magnetic powder thus obtained was placed in a flask connected with a glass tube, and chelation treatment was performed in the same manner as in Examples 1 to 12, and acetylacetone and the above-mentioned Acicular fine particle metallic iron magnetic powders were obtained which were surface treated with each chelating agent shown in Table 1 and coated with Ni. Examples 109-120 In each of Examples 97-108, Ni-coated needles were treated with the respective chelating agent in the same manner as in Examples 97-108, except that the air oxidation was omitted. Fine particle metallic iron magnetic powder was obtained. Comparative Example 1 Acicular fine particle metal iron magnetic powder was obtained in the same manner as in Example 1 except that the silicic acid hydrate deposition treatment and chelation treatment were omitted. Comparative Example 2 Acicular fine particle metallic iron magnetic powder coated with SiO 2 was obtained in the same manner as in Example 1 except that the chelation treatment was omitted. Comparative Example 3 In Example 13, acicular fine metal iron magnetic powder coated with SiO 2 was obtained in the same manner as in Example 1 except that the chelation treatment was omitted. Comparative Example 4 In Example 1, the chelation treatment of the acicular fine metallic iron magnetic powder coated with SiO 2 was omitted, and 5 g of the acicular fine metallic iron magnetic powder coated with SiO 2 was added to calcium lanophosphate in 300 ml of toluene.
It was immersed in a solution containing 500 mg and mixed with stirring for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metal iron magnetic powder whose particle surface was coated with calcium lanophosphate and SiO 2 . Comparative Example 5 In Example 13, the chelation treatment of the acicular fine metallic iron magnetic powder coated with SiO 2 was omitted, and 5 g of the acicular fine metallic iron magnetic powder coated with SiO 2 was added to 300 ml of toluene with calcium lanophosphate.
It was immersed in a solution containing 500 mg and mixed with stirring for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metal iron magnetic powder whose particle surface was coated with calcium lanophosphate and SiO 2 . Comparative Example 6 Acicular fine particle metallic iron magnetic powder coated with Al 2 O 3 was obtained in the same manner as in Example 25 except that the chelation treatment was omitted. Comparative Example 7 Acicular fine particle metallic iron magnetic powder coated with Al 2 O 3 was obtained in the same manner as in Example 37 except that the chelation treatment was omitted. Comparative Example 8 In Example 25, the chelation treatment of the acicular fine particle metal iron magnetic powder coated with Al 2 O 3 was omitted, and 5 g of the acicular fine particle metal iron magnetic powder coated with Al 2 O 3 was added to toluene. Calcium lanophosphate in 300ml
The sample was immersed in a solution containing 500 mg and stirred and mixed for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metallic iron magnetic powder whose particle surface was coated with calcium lanophosphate and Al 2 O 3 . Comparative Example 9 In Example 37, the chelation treatment of the acicular fine particle metal iron magnetic powder coated with Al 2 O 3 was omitted, and 5 g of the acicular fine particle metal iron magnetic powder coated with Al 2 O 3 was added to toluene. Calcium lanophosphate in 300ml
The sample was immersed in a solution containing 500 mg and stirred and mixed for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metallic iron magnetic powder whose particle surface was coated with calcium lanophosphate and Al 2 O 3 . Comparative Example 10 Acicular fine particle metallic iron magnetic powder coated with Ni 3 Fe was obtained in the same manner as in Example 49 except that the chelation treatment was omitted. Comparative Example 11 Acicular fine particle metallic iron magnetic powder coated with Ni 3 Fe was obtained in the same manner as in Example 61 except that the chelation treatment was omitted. Comparative Example 12 In Example 49, the chelation treatment of the Ni 3 Fe-coated acicular fine particle metal iron magnetic powder was omitted, and 5 g of the Ni 3 Fe-coated acicular fine particle metal iron magnetic powder was added to 300 ml of toluene. Calcium lanophosphate
It was immersed in a solution containing 500 mg and mixed with stirring for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metallic iron magnetic powder whose particle surface was coated with calcium lanophosphate and Ni 3 Fe. Comparative Example 13 In Example 61, the chelation treatment of the acicular fine particle metal iron magnetic powder coated with Ni 3 Fe was omitted, and 5 g of the acicular fine particle metal iron magnetic powder coated with Ni 3 Fe was added to 300 ml of toluene. Calcium lanophosphate
It was immersed in a solution containing 500 mg and mixed with stirring for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metallic iron magnetic powder whose particle surface was coated with calcium lanophosphate and Ni 3 Fe. Comparative Example 14 Acicular fine metal iron magnetic powder coated with Cu was obtained in the same manner as in Example 73, except that the chelation treatment was omitted. Comparative Example 15 Acicular fine metal iron magnetic powder coated with Cu was obtained in the same manner as in Example 85 except that the chelation treatment was omitted. Comparative Example 16 In Example 73, the chelation treatment of the acicular fine metal iron magnetic powder coated with Cu was omitted, and this
5g of acicular fine particle metallic iron magnetic powder coated with Cu
, 500mg of calcium lanophosphate in 300ml of toluene
was immersed in a solution containing the following substances and stirred and mixed for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metal iron magnetic powder whose particle surface was coated with calcium lanophosphate and Cu. Comparative Example 17 In Example 85, the chelation treatment of the acicular fine metal iron magnetic powder coated with Cu was omitted, and this
5g of acicular fine particle metallic iron magnetic powder coated with Cu
, 500mg of calcium lanophosphate in 300ml of toluene
was immersed in a solution containing the following substances and stirred and mixed for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metal iron magnetic powder whose particle surface was coated with calcium lanophosphate and Cu. Comparative Example 18 Ni-coated acicular fine particle metallic iron magnetic powder was obtained in the same manner as in Example 97, except that the chelation treatment was omitted. Comparative Example 19 Ni-coated acicular fine particle metal iron magnetic powder was obtained in the same manner as in Example 109, except that the chelation treatment was omitted. Comparative Example 20 In Example 97, the chelation treatment of the acicular fine metal iron magnetic powder coated with Ni was omitted, and this
5g of acicular fine particle metallic iron magnetic powder coated with Ni
, 500mg of calcium lanophosphate in 300ml of toluene
was immersed in a solution containing the following substances and stirred and mixed for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metal iron magnetic powder whose particle surface was coated with calcium lanophosphate and Ni. Comparative Example 21 In Example 109, the chelation treatment of the acicular fine metal iron magnetic powder coated with Ni was omitted, and this
5g of acicular fine particle metallic iron magnetic powder coated with Ni
, 500mg of calcium lanophosphate in 300ml of toluene
was immersed in a solution containing dissolved , and stirred and mixed for 30 minutes. Thereafter, it was filtered and dried at room temperature to obtain acicular fine particle metal iron magnetic powder whose particle surface was coated with calcium lanophosphate and Ni. The acicular fine particle metal magnetic powder obtained in each Example and each Comparative Example was tested for oxidation stability.
The oxidation stability test was conducted by measuring the oxidation acceleration temperature (ignition point) of each acicular fine particle metal iron magnetic powder in air using a differential thermal analyzer. Tables 2 and 3 below are the results.
【表】【table】
上表から明らかなように、この発明で得られた
針状微粒子金属磁性粉末（実施例１〜120）は従
来の針状微粒子金属磁性粉末（比較例１〜21）に
比し、いずれも発火点が高く、このことからこの
発明によつて得られる金属磁性粉末は酸化安定性
に優れていることがわかる。
As is clear from the above table, the acicular fine particle metal magnetic powders obtained by the present invention (Examples 1 to 120) are less ignitable than the conventional acicular fine particle metal magnetic powders (Comparative Examples 1 to 21). This indicates that the metal magnetic powder obtained by the present invention has excellent oxidation stability.
Claims (1)
Cu、Niから選ばれる少なくとも１種からなる被
膜を設け、さらにこの被膜上にキレート化剤を存
在させてなる金属磁性粉末。 ２ 粉末粒子表面に、SiO2、Al2O3、Ni3Fe、
Cu、Niから選ばれる少なくとも１種からなる被
膜を設け、さらにこの被膜上に酸化処理を施しキ
レート化剤を存在させてなる金属磁性粉末。[Claims] 1. SiO 2 , Al 2 O 3 , Ni 3 Fe,
A metal magnetic powder comprising a coating made of at least one selected from Cu and Ni, and a chelating agent present on the coating. 2 SiO 2 , Al 2 O 3 , Ni 3 Fe,
A metal magnetic powder comprising a coating made of at least one selected from Cu and Ni, and further oxidizing the coating so that a chelating agent is present.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60001672A JPS61160905A (en) | 1985-01-09 | 1985-01-09 | Magnetic metal powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60001672A JPS61160905A (en) | 1985-01-09 | 1985-01-09 | Magnetic metal powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61160905A JPS61160905A (en) | 1986-07-21 |
| JPH0578926B2 true JPH0578926B2 (en) | 1993-10-29 |
Family
ID=11508006
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60001672A Granted JPS61160905A (en) | 1985-01-09 | 1985-01-09 | Magnetic metal powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61160905A (en) |
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|---|---|---|---|---|
| JP4807347B2 (en) * | 2007-10-29 | 2011-11-02 | 住友金属鉱山株式会社 | Method for producing oxide-coated copper fine particles |
| JP5660566B2 (en) * | 2010-07-23 | 2015-01-28 | 富士フイルム株式会社 | Magnetic particles and method for producing the same |
| JP5808010B2 (en) * | 2011-11-25 | 2015-11-10 | 新日鉄住金化学株式会社 | Dispersible nickel fine particle composition |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5163494A (en) * | 1974-11-21 | 1976-06-01 | Fuji Photo Film Co Ltd | |
| JPS52134858A (en) * | 1976-05-07 | 1977-11-11 | Kanto Denka Kogyo Kk | Method of making magnetic recording magnetic powder containing iron as main constituent |
| JPS5378096A (en) * | 1976-12-20 | 1978-07-11 | Hitachi Maxell | Magnetic metal powder for magnetic recording and method of manufacturing same |
| JPS5698401A (en) * | 1980-01-10 | 1981-08-07 | Mitsui Toatsu Chem Inc | Ferromagnetic metal powder with improved oxidation stability and preparation thereof |
| JPS5877505A (en) * | 1981-11-04 | 1983-05-10 | Kawasaki Steel Corp | Production of metallic magnetic powder |
| JPS59155106A (en) * | 1983-02-23 | 1984-09-04 | Hitachi Maxell Ltd | Manufacture of magnetic metal powder |
| JPS59157205A (en) * | 1983-02-23 | 1984-09-06 | Hitachi Maxell Ltd | Production of metallic magnetic powder |
-
1985
- 1985-01-09 JP JP60001672A patent/JPS61160905A/en active Granted
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5163494A (en) * | 1974-11-21 | 1976-06-01 | Fuji Photo Film Co Ltd | |
| JPS52134858A (en) * | 1976-05-07 | 1977-11-11 | Kanto Denka Kogyo Kk | Method of making magnetic recording magnetic powder containing iron as main constituent |
| JPS5378096A (en) * | 1976-12-20 | 1978-07-11 | Hitachi Maxell | Magnetic metal powder for magnetic recording and method of manufacturing same |
| JPS5698401A (en) * | 1980-01-10 | 1981-08-07 | Mitsui Toatsu Chem Inc | Ferromagnetic metal powder with improved oxidation stability and preparation thereof |
| JPS5877505A (en) * | 1981-11-04 | 1983-05-10 | Kawasaki Steel Corp | Production of metallic magnetic powder |
| JPS59155106A (en) * | 1983-02-23 | 1984-09-04 | Hitachi Maxell Ltd | Manufacture of magnetic metal powder |
| JPS59157205A (en) * | 1983-02-23 | 1984-09-06 | Hitachi Maxell Ltd | Production of metallic magnetic powder |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61160905A (en) | 1986-07-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |