CA1062854A - Water based magnetic inks and the manufacture thereof - Google Patents
Water based magnetic inks and the manufacture thereofInfo
- Publication number
- CA1062854A CA1062854A CA232,198A CA232198A CA1062854A CA 1062854 A CA1062854 A CA 1062854A CA 232198 A CA232198 A CA 232198A CA 1062854 A CA1062854 A CA 1062854A
- Authority
- CA
- Canada
- Prior art keywords
- ink
- magnetic particles
- acid
- cationic surfactant
- magnetic
- 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
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 21
- 238000004519 manufacturing process Methods 0.000 title claims abstract 3
- 239000000976 ink Substances 0.000 title abstract description 17
- 239000006249 magnetic particle Substances 0.000 claims abstract description 24
- -1 unsaturated aliphatic fatty acid Chemical class 0.000 claims abstract description 15
- 239000000080 wetting agent Substances 0.000 claims abstract description 14
- 239000004094 surface-active agent Substances 0.000 claims abstract description 13
- 125000002091 cationic group Chemical group 0.000 claims abstract description 11
- 230000002776 aggregation Effects 0.000 claims abstract description 8
- SECPZKHBENQXJG-FPLPWBNLSA-N palmitoleic acid Chemical compound CCCCCC\C=C/CCCCCCCC(O)=O SECPZKHBENQXJG-FPLPWBNLSA-N 0.000 claims abstract description 8
- 238000005054 agglomeration Methods 0.000 claims abstract description 7
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 claims abstract description 6
- OYHQOLUKZRVURQ-NTGFUMLPSA-N (9Z,12Z)-9,10,12,13-tetratritiooctadeca-9,12-dienoic acid Chemical compound C(CCCCCCC\C(=C(/C\C(=C(/CCCCC)\[3H])\[3H])\[3H])\[3H])(=O)O OYHQOLUKZRVURQ-NTGFUMLPSA-N 0.000 claims abstract description 4
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 claims abstract description 4
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 claims abstract description 4
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000005642 Oleic acid Substances 0.000 claims abstract description 4
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 claims abstract description 4
- 235000021319 Palmitoleic acid Nutrition 0.000 claims abstract description 4
- DTOSIQBPPRVQHS-PDBXOOCHSA-N alpha-linolenic acid Chemical compound CC\C=C/C\C=C/C\C=C/CCCCCCCC(O)=O DTOSIQBPPRVQHS-PDBXOOCHSA-N 0.000 claims abstract description 4
- 235000020661 alpha-linolenic acid Nutrition 0.000 claims abstract description 4
- SECPZKHBENQXJG-UHFFFAOYSA-N cis-palmitoleic acid Natural products CCCCCCC=CCCCCCCCC(O)=O SECPZKHBENQXJG-UHFFFAOYSA-N 0.000 claims abstract description 4
- 235000014113 dietary fatty acids Nutrition 0.000 claims abstract description 4
- 239000000194 fatty acid Substances 0.000 claims abstract description 4
- 229930195729 fatty acid Natural products 0.000 claims abstract description 4
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229960004488 linolenic acid Drugs 0.000 claims abstract description 4
- KQQKGWQCNNTQJW-UHFFFAOYSA-N linolenic acid Natural products CC=CCCC=CCC=CCCCCCCCC(O)=O KQQKGWQCNNTQJW-UHFFFAOYSA-N 0.000 claims abstract description 4
- YWWVWXASSLXJHU-WAYWQWQTSA-N myristoleic acid Chemical compound CCCC\C=C/CCCCCCCC(O)=O YWWVWXASSLXJHU-WAYWQWQTSA-N 0.000 claims abstract description 4
- 235000021313 oleic acid Nutrition 0.000 claims abstract description 4
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 claims description 28
- 238000000034 method Methods 0.000 claims description 16
- 239000003093 cationic surfactant Substances 0.000 claims description 13
- 125000000217 alkyl group Chemical group 0.000 claims description 11
- 150000001875 compounds Chemical class 0.000 claims description 7
- 150000003868 ammonium compounds Chemical class 0.000 claims description 6
- 239000004721 Polyphenylene oxide Substances 0.000 claims description 5
- 229920000570 polyether Polymers 0.000 claims description 5
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 claims description 4
- 150000001450 anions Chemical class 0.000 claims description 3
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 229910052736 halogen Inorganic materials 0.000 claims description 3
- 239000006185 dispersion Substances 0.000 claims description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims 4
- 125000002877 alkyl aryl group Chemical group 0.000 claims 4
- 239000003795 chemical substances by application Substances 0.000 claims 3
- 239000002253 acid Substances 0.000 claims 2
- 125000003282 alkyl amino group Chemical group 0.000 claims 2
- 239000003006 anti-agglomeration agent Substances 0.000 claims 1
- 239000002245 particle Substances 0.000 abstract description 19
- 239000000696 magnetic material Substances 0.000 abstract description 11
- 238000002360 preparation method Methods 0.000 abstract description 5
- 239000000203 mixture Substances 0.000 description 6
- 239000003125 aqueous solvent Substances 0.000 description 5
- 238000009388 chemical precipitation Methods 0.000 description 4
- 239000011554 ferrofluid Substances 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 150000003863 ammonium salts Chemical class 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 125000006353 oxyethylene group Chemical group 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical class S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 2
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 2
- IGFHQQFPSIBGKE-UHFFFAOYSA-N Nonylphenol Natural products CCCCCCCCCC1=CC=C(O)C=C1 IGFHQQFPSIBGKE-UHFFFAOYSA-N 0.000 description 2
- 150000003973 alkyl amines Chemical class 0.000 description 2
- 150000001412 amines Chemical class 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- DIOQZVSQGTUSAI-UHFFFAOYSA-N decane Chemical compound CCCCCCCCCC DIOQZVSQGTUSAI-UHFFFAOYSA-N 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 239000002612 dispersion medium Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000016615 flocculation Effects 0.000 description 2
- 238000005189 flocculation Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 238000007641 inkjet printing Methods 0.000 description 2
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 2
- SNQQPOLDUKLAAF-UHFFFAOYSA-N nonylphenol Chemical compound CCCCCCCCCC1=CC=CC=C1O SNQQPOLDUKLAAF-UHFFFAOYSA-N 0.000 description 2
- 229940049964 oleate Drugs 0.000 description 2
- 150000004714 phosphonium salts Chemical class 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 238000007639 printing Methods 0.000 description 2
- 229920002545 silicone oil Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- RWSOTUBLDIXVET-UHFFFAOYSA-O sulfonium Chemical compound [SH3+] RWSOTUBLDIXVET-UHFFFAOYSA-O 0.000 description 2
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 2
- DUIOKRXOKLLURE-UHFFFAOYSA-N 2-octylphenol Chemical group CCCCCCCCC1=CC=CC=C1O DUIOKRXOKLLURE-UHFFFAOYSA-N 0.000 description 1
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical class [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- JZUFKLXOESDKRF-UHFFFAOYSA-N Chlorothiazide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC2=C1NCNS2(=O)=O JZUFKLXOESDKRF-UHFFFAOYSA-N 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- XSTXAVWGXDQKEL-UHFFFAOYSA-N Trichloroethylene Chemical group ClC=C(Cl)Cl XSTXAVWGXDQKEL-UHFFFAOYSA-N 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 150000007933 aliphatic carboxylic acids Chemical class 0.000 description 1
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 239000007900 aqueous suspension Substances 0.000 description 1
- 239000003849 aromatic solvent Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 150000001721 carbon Chemical group 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 150000001767 cationic compounds Chemical class 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000001246 colloidal dispersion Methods 0.000 description 1
- 238000010908 decantation Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 229910001447 ferric ion Inorganic materials 0.000 description 1
- 229960002089 ferrous chloride Drugs 0.000 description 1
- 229910001448 ferrous ion Inorganic materials 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 230000008570 general process Effects 0.000 description 1
- 150000008282 halocarbons Chemical class 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 150000008040 ionic compounds Chemical class 0.000 description 1
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- 239000003350 kerosene Substances 0.000 description 1
- 239000011553 magnetic fluid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 235000010446 mineral oil Nutrition 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002736 nonionic surfactant Substances 0.000 description 1
- 125000001400 nonyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 125000005064 octadecenyl group Chemical group C(=CCCCCCCCCCCCCCCCC)* 0.000 description 1
- 125000002347 octyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 125000000913 palmityl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 125000004079 stearyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- UBOXGVDOUJQMTN-UHFFFAOYSA-N trichloroethylene Natural products ClCC(Cl)Cl UBOXGVDOUJQMTN-UHFFFAOYSA-N 0.000 description 1
- GPRLSGONYQIRFK-MNYXATJNSA-N triton Chemical compound [3H+] GPRLSGONYQIRFK-MNYXATJNSA-N 0.000 description 1
- 235000021122 unsaturated fatty acids Nutrition 0.000 description 1
- 150000004670 unsaturated fatty acids Chemical class 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/14—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for applying magnetic films to substrates
- H01F41/16—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for applying magnetic films to substrates the magnetic material being applied in the form of particles, e.g. by serigraphy, to form thick magnetic films or precursors therefor
-
- 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
- H01F1/44—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of magnetic liquids, e.g. ferrofluids
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Inks, Pencil-Leads, Or Crayons (AREA)
- Wet Developing In Electrophotography (AREA)
- Soft Magnetic Materials (AREA)
- Paints Or Removers (AREA)
Abstract
WATER BASED MAGNETIC INKS AND THE MANUFACTURE THEREOF
Abstract of the Disclosure Finely divided magnetic particles are rendered water-dispensible through the aid of a combination of one or more nonionic wetting agents and one or more cationic surface active agents. The magnetic material particles, as used in a magnetic ink, are 50 to 300 .ANG. in size and are pre-coated with a long chain unsaturated aliphatic fatty acid about C8 to C24, such as oleic acid, linoleic acid, linolenic acid, myristolenic acid, or palmitoleic acid, to maintain desired size particles while preventing agglomeration during preparation and initial water dispension.
Abstract of the Disclosure Finely divided magnetic particles are rendered water-dispensible through the aid of a combination of one or more nonionic wetting agents and one or more cationic surface active agents. The magnetic material particles, as used in a magnetic ink, are 50 to 300 .ANG. in size and are pre-coated with a long chain unsaturated aliphatic fatty acid about C8 to C24, such as oleic acid, linoleic acid, linolenic acid, myristolenic acid, or palmitoleic acid, to maintain desired size particles while preventing agglomeration during preparation and initial water dispension.
Description
~062854 1 Background of the Invention Magnetic inks are known formed of magnetic material dis-persed in a liquid carrier.
The magnetic material is typically magnetite (Fe304),~f -Fe203 and the 1ike. The magnetic material, in extremely finely div-ided form of the order of submicron size, is more or less permanently suspended in a liquid carrier with the aid of dispersing agents, surfactants, and the like to form a colloidal magnetic fluid, typic-ally referred to as a ferrofluid.
The liquid carrier employed is usually a non-aqueous sol-vent, often an organic solvent of the non-polar type. Examples of non-aqueous solvents usable in the preparation of ferrofluids are aliphatic hydrocarbons, such as heptane, decane, mineral oil, kerosene, and the like, halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene and the like, aromatic solvents such as benzene, toluene and the like, silicone oils, etc.
The dispersing aid is included in the ferrofluid formulation to prevent aggregation of magnetic material particles in the non-aqueous solvent, which could lead to flocculation and deposition out of suspension of magnetic material. The dispersing aid, which may be one or more surfactants, wetting agents and the like, is applied to coat the surfaces of the individual magnetic particles so as to form a coating around the individual magnetic particles to prevent agglomeration or flocculation due to attraction therebetween.
Aliphatic carboxylic acids having about 8 to 24 carbon atoms are known as dispersing aids for magnetic material, such as magnetite, to be colloidally suspended in non-aqueous solvents. In this regard, see U.S. 3,531,413 and U.S. 3,764,540.
For certain applications of magnetic inks it is desirable to employ water as the carrier fluid for the magnetic material in ~P
1 place of the more commonly used non-aqueous solvents. The present invention is directed to the preparation of colloidal suspensions of magnetic material, such as magnetite, in an aqueous medium, and the ferrofluid so produced.
Accordingly, it is an object of the present invention to provide a method for forming a colloidal suspension of magnetic particles, particularly magnetite, in water.
Another object of this invention is to provide an aqueous based magnetic ink.
A further object of this invention is to provide a specific combination of dispersing aids which can be employed to colloidally disperse magnetite in water.
Summary of the Invention In accordance with the present invention, finely divided magnetic particles are rendered water-dispersible through the aid of a combination of one or more non-ionic wetting agents and one or more cationic surface active agents.
In a preferred embodiment of this invention, the magnetic material particles are 50 to 300 A in size, more preferably 75 to 200 A, and are pre-coated with a long chain unsaturated aliphatic fatty acid about C8 to C24, such as oleic acid, linoleic acid, linolenic acid, myristolenic acid, or palmitoleic acid, to maintain desired size particles while preventing agglomeration during pre-paration thereof and initial water dispersion. Other aids to pre-vent agglomeration could be employed in this invention.
This non-ionic wetting agent is selected to provide a bridge between the lyophilic disperse phase, i.e., magnetite, and the aqueous dispersion medium.
The cationic surface active agent is selected to impart a 0 relatively large charge on the magnetite particles, say of the 11~6Z~5~
1 order of a zeta potential of +30 to +100 mV. Quartenary ammon-ium salts, amines and quartenary sulfonium or phosphonium compounds are exemplary of the kinds of cationic surface active agents used in the present invention.
Detailed Description of the Invention Magnetic inks are used in magnetic ink jet printing where a stream of ink is supplied under pressure and periodically inter-rupted to produce droplets, which impinge upon a sheet of moving paper. To obtain printing on the paper by the ink, it is necessary that the droplets be spaced substantially uniform distances from each other, be of uniform size, and be formed at a high rate such as about 10 per second.
Magnetic ink is preferably isotropic and virtually free of remanence. Magnetic ink suitable for ink jet printing is described in this invention.
In order to prepare an aqueous based magnetic pringing ink, it is necessary to have available magnetic particles of small size characterized by high magnetic moment. Using magnetite as an example, the particle size range should be about 50 to 300 A, pre-ferably about 75 to 200 A. Magnetic moment, bearing in mind the above disclosed use for aqueous magnetic inks of the present invention, should desirably be within the range of about 65 to 80 emu.lgram of dried, e.g., air or vacuum, magnetic material, prefer-ably about 70 emu./gram. Dispersed magnetite of size and magnetic moment disclosed above, is available from a number of commercial sources such as Sherritt Gordon Mines, Ltd., Canada, or may be prepared in a manner well known in the art. For example, the follow-ing general process may be employed.
Ferric chloride and ferrous chloride are dissolved in separate bodies of water to form solutions thereof. The solutions 1 are m;xed in amounts to mainta;n the molar ratio Fe 3/Fe 2 slightly under the theoretical value of 2.0 without de-aerating the solutions.
Oxygen in the solution will oxidize some ferrous ions to ferric ions.
Magnetitie, Fe304, can be formed by chemical precipitation of the ferrous-ferric mixture with base, such as ammonium hydrozide. In order to favor a high rate of magnetite nucleation coupled with a slow rate of particle growth, chemical precipitation can be carried out at low temperatures, for example, in an ultrasonic bath main-tained at about 5 to 12C. The pH of the mixture during chemical precipitation for deposition of magnetite is maintained between about 8.9 and 10.2, preferred pH is 9.5, with the amount of hydroxide used being adjusted accordingly.
In order to aid in the prevention of agglomeration of mag-netite during and immediately subsequent to chemical precipitation, a dispersing aid is added to the precipitation mixture within a few seconds of hydroxide addition. Ancillary to agglomeration prevention, the dispersing aid will also help maintain desired small particle size. The dispersing aid is selected from those materials known to prevent inter-particle attraction between individual magnetite particles. As discussed above, 8 to 24 carbon atom aliphatic mono-carboxylic acids can be employed for this purpose. Finally, the carboxylic acid coated magnetic particles in aqueous suspension are heated to about 60 to 100C, to increase the magnetic moment thereof and the pH of the mixture is decreased from about 8 to 6 to aid in precipitation of the coated magnetite particles. Then, the particles are rinsed with distilled water to remove NH4Cl salt and separation can be carried out in any conventional manner, such as by use of the ultracentrifuge.
Once magnetite particles of the preferred 75 to 200 A size have been obtained or prepared as above, they are rendered water 1 dispersible to form a colloidal dispersion in water by dispersing them in combination with the two-component dispersing aid of the invention. Both non-ionic and cationic are absorbed on the surface of the magnetite particles.
The amount and type of non-ionic wetting agent is selected to provide an interfacial tension between magnetite particles and water of about 24 to 36 dynes/cm, preferably about 30 to 34 dynes per cm. Generally, about 5 to 10 weight percent based on magnetite of non-ionic wetting agent will be sufficient, preferably about 7 weight percent.
As noted above, the non-ionic wetting agent is selected to provide a bridge between the lyophilic disperse phase, i.e., magne-tite, and the dispersion medium of water. Non-ionics based on poly-oxyethylene, due to the hydrophilic nature of the polyoxyethylene chains, are suitable for use in the present invention. Alkylaryl-polyether alcohols or alkylphenol ethers of polyethylene glycol wherein the alkyl chain is of C25 to C45 and containing from 8 to 15 oxyethylene units can be employed, for example, of the formula:
R ~ OCH2CH2 ) xH
wherein R is the alkyl chain and x designates the number of oxyethy-lene units present. The octyl or nonyl compounds wherein x is 9 or 10, are preferred due to their excellent water solubility and reasonable viscosity, for example, nonyl phenol or tertiary octyl phenol polyoxyethylenated with 9 to 10 moles of ethylene oxide.
The amount and type of cationic surface active agent is selected to impart a zeta potential of about +30 to +100 mv, pre-ferably about +60 to +90 mv, to the magnetite particles.
Usable cationics are quarternary compounds and amines, such 1 as the quarternary ammonium salts, alkyl amines, quarternary sulfonium compounds, quarternary phosphonium compounds and ethoxy-lated quarternary ammonium compounds.
These cationics will generally be used in the concentration of 2-15 based on magnetite, preferably 6% by weight.
As examples of quarternary ammonium salts, there may be mentioned compounds of the formula:
CH3 +
Rl wherein R and Rl are the same or different and are about 8 to 24 car-bon atom branched or straight chain alkyl or benzyl radicals and preferably R and Rl are C12 to C18 groups. A minor amount of unsat-uration may be present in R and Rl. X is a suitable anion such as a halogen ion.
As examples of sulfonium compounds, there may be mentioned compounds of the formula:
R
R S+ X
L R _ l As examples of phosphonium cationics there may be mentioned compounds of the formula:
¦ R i LR P - R Cl R
In the above sulfonium and phosphorium compounds the R
groups are the same or different Cl to C24 alkyl groups, with pre-ferably two of the R groups being methyl and the other(s) being at least C8.
As examples of amine cationics, there may be mentioned long chain alkylamines. Since there surfactants are pH sensitive, care must be exercised in their use.
EXAMPLE
This example illustrates the preparation of a magnetic ink in accordance with the present invention.
As the magnetite particles, magnetite prepared by any prior art method coated with unsaturated fatty acid such as oleate, is used.
Oleate-coated magnetite particles (190 grams) are added to a suitable mixing apparatus such as an attritor along with a solution of 2 grams of potassium hydroxide and 2 grams of Ardefoam** (mineral and silicone oils available from the Armak Chemical Division of Alzona, Inc., of Chicago, Illinois, to act as a bubble breaker during the magnetic printing operation~.
Thereafter, a solution of cationic and nonionic surfactants is added thereto.
This solution is prepared by first dissolving 30 grams of Triton** N-101 (a polyoxyethylenated nonyl phenol containing 9 to 10 moles ethylene oxide per mol available from Rohm and Haas Co.,) in 100 ml. of water. Then 10 grams of Arquad** 2H-75 (a dimethyldialkyl quarternary ammonium compound of 575 molecular weight wherein the dialkyl groups are 24% saturated hexadecyl, 75% saturated octadecyl and 1% unsaturated octadecenyl and having 75%* acti-vity (available from Armak Chemical Division). Following 2 hours in the attritor, the mixture is heated in a boiling bath of water for 3 hours, after which it is cooled to room temperature and centrifuged for 45 minutes at 3000 rpm. The fluid remaining after decantation is useable as a magnetic ink.
Typical data for the magnetic ink is as follows:
Magnetic moment - 25-30 emu/gram * Weight percentages in this specification are based 100% activity of non-ionic and cationic compounds.
** Trade Mark 1 Weight of ink - 400-450 grams Viscosity - 11-17 cps Surface Tension - 28-35 dynes/cm pH - 6 - 8 Resistivity - 80-140 ~ cm While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
The magnetic material is typically magnetite (Fe304),~f -Fe203 and the 1ike. The magnetic material, in extremely finely div-ided form of the order of submicron size, is more or less permanently suspended in a liquid carrier with the aid of dispersing agents, surfactants, and the like to form a colloidal magnetic fluid, typic-ally referred to as a ferrofluid.
The liquid carrier employed is usually a non-aqueous sol-vent, often an organic solvent of the non-polar type. Examples of non-aqueous solvents usable in the preparation of ferrofluids are aliphatic hydrocarbons, such as heptane, decane, mineral oil, kerosene, and the like, halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene and the like, aromatic solvents such as benzene, toluene and the like, silicone oils, etc.
The dispersing aid is included in the ferrofluid formulation to prevent aggregation of magnetic material particles in the non-aqueous solvent, which could lead to flocculation and deposition out of suspension of magnetic material. The dispersing aid, which may be one or more surfactants, wetting agents and the like, is applied to coat the surfaces of the individual magnetic particles so as to form a coating around the individual magnetic particles to prevent agglomeration or flocculation due to attraction therebetween.
Aliphatic carboxylic acids having about 8 to 24 carbon atoms are known as dispersing aids for magnetic material, such as magnetite, to be colloidally suspended in non-aqueous solvents. In this regard, see U.S. 3,531,413 and U.S. 3,764,540.
For certain applications of magnetic inks it is desirable to employ water as the carrier fluid for the magnetic material in ~P
1 place of the more commonly used non-aqueous solvents. The present invention is directed to the preparation of colloidal suspensions of magnetic material, such as magnetite, in an aqueous medium, and the ferrofluid so produced.
Accordingly, it is an object of the present invention to provide a method for forming a colloidal suspension of magnetic particles, particularly magnetite, in water.
Another object of this invention is to provide an aqueous based magnetic ink.
A further object of this invention is to provide a specific combination of dispersing aids which can be employed to colloidally disperse magnetite in water.
Summary of the Invention In accordance with the present invention, finely divided magnetic particles are rendered water-dispersible through the aid of a combination of one or more non-ionic wetting agents and one or more cationic surface active agents.
In a preferred embodiment of this invention, the magnetic material particles are 50 to 300 A in size, more preferably 75 to 200 A, and are pre-coated with a long chain unsaturated aliphatic fatty acid about C8 to C24, such as oleic acid, linoleic acid, linolenic acid, myristolenic acid, or palmitoleic acid, to maintain desired size particles while preventing agglomeration during pre-paration thereof and initial water dispersion. Other aids to pre-vent agglomeration could be employed in this invention.
This non-ionic wetting agent is selected to provide a bridge between the lyophilic disperse phase, i.e., magnetite, and the aqueous dispersion medium.
The cationic surface active agent is selected to impart a 0 relatively large charge on the magnetite particles, say of the 11~6Z~5~
1 order of a zeta potential of +30 to +100 mV. Quartenary ammon-ium salts, amines and quartenary sulfonium or phosphonium compounds are exemplary of the kinds of cationic surface active agents used in the present invention.
Detailed Description of the Invention Magnetic inks are used in magnetic ink jet printing where a stream of ink is supplied under pressure and periodically inter-rupted to produce droplets, which impinge upon a sheet of moving paper. To obtain printing on the paper by the ink, it is necessary that the droplets be spaced substantially uniform distances from each other, be of uniform size, and be formed at a high rate such as about 10 per second.
Magnetic ink is preferably isotropic and virtually free of remanence. Magnetic ink suitable for ink jet printing is described in this invention.
In order to prepare an aqueous based magnetic pringing ink, it is necessary to have available magnetic particles of small size characterized by high magnetic moment. Using magnetite as an example, the particle size range should be about 50 to 300 A, pre-ferably about 75 to 200 A. Magnetic moment, bearing in mind the above disclosed use for aqueous magnetic inks of the present invention, should desirably be within the range of about 65 to 80 emu.lgram of dried, e.g., air or vacuum, magnetic material, prefer-ably about 70 emu./gram. Dispersed magnetite of size and magnetic moment disclosed above, is available from a number of commercial sources such as Sherritt Gordon Mines, Ltd., Canada, or may be prepared in a manner well known in the art. For example, the follow-ing general process may be employed.
Ferric chloride and ferrous chloride are dissolved in separate bodies of water to form solutions thereof. The solutions 1 are m;xed in amounts to mainta;n the molar ratio Fe 3/Fe 2 slightly under the theoretical value of 2.0 without de-aerating the solutions.
Oxygen in the solution will oxidize some ferrous ions to ferric ions.
Magnetitie, Fe304, can be formed by chemical precipitation of the ferrous-ferric mixture with base, such as ammonium hydrozide. In order to favor a high rate of magnetite nucleation coupled with a slow rate of particle growth, chemical precipitation can be carried out at low temperatures, for example, in an ultrasonic bath main-tained at about 5 to 12C. The pH of the mixture during chemical precipitation for deposition of magnetite is maintained between about 8.9 and 10.2, preferred pH is 9.5, with the amount of hydroxide used being adjusted accordingly.
In order to aid in the prevention of agglomeration of mag-netite during and immediately subsequent to chemical precipitation, a dispersing aid is added to the precipitation mixture within a few seconds of hydroxide addition. Ancillary to agglomeration prevention, the dispersing aid will also help maintain desired small particle size. The dispersing aid is selected from those materials known to prevent inter-particle attraction between individual magnetite particles. As discussed above, 8 to 24 carbon atom aliphatic mono-carboxylic acids can be employed for this purpose. Finally, the carboxylic acid coated magnetic particles in aqueous suspension are heated to about 60 to 100C, to increase the magnetic moment thereof and the pH of the mixture is decreased from about 8 to 6 to aid in precipitation of the coated magnetite particles. Then, the particles are rinsed with distilled water to remove NH4Cl salt and separation can be carried out in any conventional manner, such as by use of the ultracentrifuge.
Once magnetite particles of the preferred 75 to 200 A size have been obtained or prepared as above, they are rendered water 1 dispersible to form a colloidal dispersion in water by dispersing them in combination with the two-component dispersing aid of the invention. Both non-ionic and cationic are absorbed on the surface of the magnetite particles.
The amount and type of non-ionic wetting agent is selected to provide an interfacial tension between magnetite particles and water of about 24 to 36 dynes/cm, preferably about 30 to 34 dynes per cm. Generally, about 5 to 10 weight percent based on magnetite of non-ionic wetting agent will be sufficient, preferably about 7 weight percent.
As noted above, the non-ionic wetting agent is selected to provide a bridge between the lyophilic disperse phase, i.e., magne-tite, and the dispersion medium of water. Non-ionics based on poly-oxyethylene, due to the hydrophilic nature of the polyoxyethylene chains, are suitable for use in the present invention. Alkylaryl-polyether alcohols or alkylphenol ethers of polyethylene glycol wherein the alkyl chain is of C25 to C45 and containing from 8 to 15 oxyethylene units can be employed, for example, of the formula:
R ~ OCH2CH2 ) xH
wherein R is the alkyl chain and x designates the number of oxyethy-lene units present. The octyl or nonyl compounds wherein x is 9 or 10, are preferred due to their excellent water solubility and reasonable viscosity, for example, nonyl phenol or tertiary octyl phenol polyoxyethylenated with 9 to 10 moles of ethylene oxide.
The amount and type of cationic surface active agent is selected to impart a zeta potential of about +30 to +100 mv, pre-ferably about +60 to +90 mv, to the magnetite particles.
Usable cationics are quarternary compounds and amines, such 1 as the quarternary ammonium salts, alkyl amines, quarternary sulfonium compounds, quarternary phosphonium compounds and ethoxy-lated quarternary ammonium compounds.
These cationics will generally be used in the concentration of 2-15 based on magnetite, preferably 6% by weight.
As examples of quarternary ammonium salts, there may be mentioned compounds of the formula:
CH3 +
Rl wherein R and Rl are the same or different and are about 8 to 24 car-bon atom branched or straight chain alkyl or benzyl radicals and preferably R and Rl are C12 to C18 groups. A minor amount of unsat-uration may be present in R and Rl. X is a suitable anion such as a halogen ion.
As examples of sulfonium compounds, there may be mentioned compounds of the formula:
R
R S+ X
L R _ l As examples of phosphonium cationics there may be mentioned compounds of the formula:
¦ R i LR P - R Cl R
In the above sulfonium and phosphorium compounds the R
groups are the same or different Cl to C24 alkyl groups, with pre-ferably two of the R groups being methyl and the other(s) being at least C8.
As examples of amine cationics, there may be mentioned long chain alkylamines. Since there surfactants are pH sensitive, care must be exercised in their use.
EXAMPLE
This example illustrates the preparation of a magnetic ink in accordance with the present invention.
As the magnetite particles, magnetite prepared by any prior art method coated with unsaturated fatty acid such as oleate, is used.
Oleate-coated magnetite particles (190 grams) are added to a suitable mixing apparatus such as an attritor along with a solution of 2 grams of potassium hydroxide and 2 grams of Ardefoam** (mineral and silicone oils available from the Armak Chemical Division of Alzona, Inc., of Chicago, Illinois, to act as a bubble breaker during the magnetic printing operation~.
Thereafter, a solution of cationic and nonionic surfactants is added thereto.
This solution is prepared by first dissolving 30 grams of Triton** N-101 (a polyoxyethylenated nonyl phenol containing 9 to 10 moles ethylene oxide per mol available from Rohm and Haas Co.,) in 100 ml. of water. Then 10 grams of Arquad** 2H-75 (a dimethyldialkyl quarternary ammonium compound of 575 molecular weight wherein the dialkyl groups are 24% saturated hexadecyl, 75% saturated octadecyl and 1% unsaturated octadecenyl and having 75%* acti-vity (available from Armak Chemical Division). Following 2 hours in the attritor, the mixture is heated in a boiling bath of water for 3 hours, after which it is cooled to room temperature and centrifuged for 45 minutes at 3000 rpm. The fluid remaining after decantation is useable as a magnetic ink.
Typical data for the magnetic ink is as follows:
Magnetic moment - 25-30 emu/gram * Weight percentages in this specification are based 100% activity of non-ionic and cationic compounds.
** Trade Mark 1 Weight of ink - 400-450 grams Viscosity - 11-17 cps Surface Tension - 28-35 dynes/cm pH - 6 - 8 Resistivity - 80-140 ~ cm While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.
Claims (31)
1. A process for preparing an aqueous magnetic ink which consists essentially of dispersing magnetic particles in water in the presence of surface active agents consisting essentially of about 5 to 10 weight percent of a nonionic wetting agent based on weight of magnetic particles and about 2 to 15 weight percent of cationic surface active agent based on weight of magnetic particles, said nonionic wetting agent providing a surface tension between magnetic parti-cles and water of 24 to 35 dynes per centimeter and said cationic surfactant imparting a zeta potential of about +30 to +100 millivolts to the magnetic particles.
2. The process of claim 1, wherein the magnetic particles are first coated with an agent to prevent agglomeration thereon and then are dispersed in said water.
3. The process of claim 2, wherein said agent is a C8 to C24 unsaturated ali-phatic fatty acid.
4. The process of claim 3, wherein said acid is oleic acid, linoleic acid, linolenic acid, myristolenic acid or palmitoleic acid.
5. The process of claim 2, wherein the magnetic particles are 50 to 300 A.
6. The process of claim 1, wherein the nonionic wetting agent is an alkyl aryl polyether alcohol, wherein the alkyl chain contains 8 to 45 carbon atoms, and contains about 8 to 15 mols ethylene oxide per mol.
7. The process of claim 6, wherein the alkyl aryl polyether alcohol is of the formula:
wherein R is the alkyl chain and x is an integer from 9 to 10.
wherein R is the alkyl chain and x is an integer from 9 to 10.
8. The process of claim 2, wherein the cationic surfactant is an alkylamine.
9. The process of claim 2, wherein the cationic surfactant is a quarternary ammonium compound.
10. The process of claim 2, wherein the cationic surfactant is a quarternary sulfonium compound.
11. The process of claim 2, wherein the cationic surfactant is a quarternary phosphonium compound.
12. The process of claim 9 wherein the cationic surfactant is an ethoxylated quarternary ammonium compound.
13. The process of claim 9, wherein the compound is of the formula:
wherein R and R1 are the same or different C8 to C24 straight or branched chain alkyl groups and X is a suitable anion including a halogen ion.
wherein R and R1 are the same or different C8 to C24 straight or branched chain alkyl groups and X is a suitable anion including a halogen ion.
14. The process of claim 13, wherein R and R1 are C12 to C18 alkyl groups.
15. The process of claim 2, wherein the magnetic particles are magnetite.
16. An aqueous magnetic ink consisting essentially of a dispersion of magnetic particles in water in the presence of surface active agents consisting essen-tially of about 5 to 10 weight percent of a nonionic wetting agent based on weight of magnetic particles and about 2 to 15 weight percent of a cationic surface active agent based on weight of magnetic particles, said nonionic wetting agent providing a surface tension between magnetic particles and water of 24 to 36 dynes per centimeter and said cationic surfactant imparting a zeta potential of about +30 to +100 millivolts to the magnetic particles.
17. The ink of claim 16, wherein said wetting agent and surface active agent are coated on the magnetic particles.
18. The ink of claim 17, wherein the magnetic particles are pre-coated with an anti-agglomeration agent.
19. The ink of claim 18, wherein said agent is a C8 to C24 unsaturated aliph-atic fatty acid.
20. The ink of claim 19, wherein said acid is oleic acid, linoleic acid, lino-lenic acid, myristolenic acid or palmitoleic acid.
21. The ink of claim 18, wherein the magnetic particles are 50 to 300 A.
22. The ink of claim 18, wherein the nonionic wetting agent is an alkyl aryl polyether alcohol, wherein the alkyl chain contains 8 to 45 carbon atoms, and contains about 8 to 15 mols ethylene oxide per mol.
23. The ink of claim 22, wherein the alkyl aryl polyether alcohol is of the formula:
wherein R is the alkyl chain and x is an integer from 9 to 10.
wherein R is the alkyl chain and x is an integer from 9 to 10.
24. The ink of claim 18, wherein the cationic surfactant is an alkylamine.
25. The ink of claim 18, wherein the cationic surfactant is a quarternary ammonium compound.
26. The ink of claim 18, wherein the cationic surfactant is a quarternary sulfonium compound.
27. The ink of claim 18, wherein the cationic surfactant is a quarternary phosphonium compound.
28. The ink of claim 25, wherein the cationic surfactant is an ethoxylated quarternary ammonium compound.
29. The ink of claim 25, wherein the compound is of the formula:
wherein R and R1 are the same or different C8 to C24 straight or branched chain alkyl groups, and X is a suitable anion including a halogen ion.
wherein R and R1 are the same or different C8 to C24 straight or branched chain alkyl groups, and X is a suitable anion including a halogen ion.
30. The ink of claim 29, wherein R and R1 are C12 to C18 alkyl groups.
31. The ink of claim 18, wherein the magnetic particles are magnetite.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US49995674A | 1974-08-23 | 1974-08-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1062854A true CA1062854A (en) | 1979-09-25 |
Family
ID=23987457
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA232,198A Expired CA1062854A (en) | 1974-08-23 | 1975-07-24 | Water based magnetic inks and the manufacture thereof |
Country Status (14)
| Country | Link |
|---|---|
| JP (1) | JPS5618035B2 (en) |
| AR (1) | AR206932A1 (en) |
| AU (1) | AU496896B2 (en) |
| BE (1) | BE831315A (en) |
| BR (1) | BR7505392A (en) |
| CA (1) | CA1062854A (en) |
| CH (1) | CH614553A5 (en) |
| DE (1) | DE2529053C2 (en) |
| ES (1) | ES439588A1 (en) |
| FR (1) | FR2282460B1 (en) |
| GB (1) | GB1478088A (en) |
| IT (1) | IT1041765B (en) |
| NL (1) | NL7507910A (en) |
| SE (1) | SE422808B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2461521A1 (en) * | 1979-07-20 | 1981-02-06 | Anvar | MAGNETIC FLUIDS, IN PARTICULAR FERROFLUIDS, AND PROCESS FOR OBTAINING THEM |
| JPS6062238U (en) * | 1983-10-04 | 1985-05-01 | ヤンマー農機株式会社 | Bundling device of straw binding machine |
| JPS6099178A (en) * | 1983-11-01 | 1985-06-03 | Mitsubishi Electric Corp | Material for writing utensil |
| JPH07116399B2 (en) * | 1986-08-15 | 1995-12-13 | 株式会社リコー | Aqueous ink composition |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3471415A (en) * | 1966-12-20 | 1969-10-07 | Honora Friedman | Magnetic inks containing lecithin as a surfactant |
| US3531413A (en) * | 1967-09-22 | 1970-09-29 | Avco Corp | Method of substituting one ferrofluid solvent for another |
| US3764540A (en) * | 1971-05-28 | 1973-10-09 | Us Interior | Magnetofluids and their manufacture |
-
1975
- 1975-01-01 AR AR260108A patent/AR206932A1/en active
- 1975-05-21 GB GB2187275A patent/GB1478088A/en not_active Expired
- 1975-06-26 IT IT24792/75A patent/IT1041765B/en active
- 1975-06-30 DE DE2529053A patent/DE2529053C2/en not_active Expired
- 1975-07-03 NL NL7507910A patent/NL7507910A/en not_active Application Discontinuation
- 1975-07-03 FR FR7521478A patent/FR2282460B1/en not_active Expired
- 1975-07-11 BE BE158253A patent/BE831315A/en not_active IP Right Cessation
- 1975-07-15 JP JP8592675A patent/JPS5618035B2/ja not_active Expired
- 1975-07-21 ES ES439588A patent/ES439588A1/en not_active Expired
- 1975-07-24 CA CA232,198A patent/CA1062854A/en not_active Expired
- 1975-08-04 CH CH1012575A patent/CH614553A5/en not_active IP Right Cessation
- 1975-08-21 SE SE7509333A patent/SE422808B/en unknown
- 1975-08-22 BR BR7505392*A patent/BR7505392A/en unknown
- 1975-08-25 AU AU84252/75A patent/AU496896B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| ES439588A1 (en) | 1977-02-16 |
| JPS5618035B2 (en) | 1981-04-25 |
| AU8425275A (en) | 1977-03-03 |
| DE2529053C2 (en) | 1982-06-03 |
| AU496896B2 (en) | 1978-11-09 |
| NL7507910A (en) | 1976-02-25 |
| FR2282460B1 (en) | 1977-07-22 |
| BE831315A (en) | 1975-11-03 |
| SE7509333L (en) | 1976-02-24 |
| DE2529053A1 (en) | 1976-03-04 |
| CH614553A5 (en) | 1979-11-30 |
| GB1478088A (en) | 1977-06-29 |
| AR206932A1 (en) | 1976-08-31 |
| JPS5137705A (en) | 1976-03-30 |
| SE422808B (en) | 1982-03-29 |
| IT1041765B (en) | 1980-01-10 |
| FR2282460A1 (en) | 1976-03-19 |
| BR7505392A (en) | 1976-08-03 |
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