US3574683A - Preparation of magnetic particles by reacting iron,cobalt,or nickel salts with phthalate ion in dialkyl sulfoxide - Google Patents

Preparation of magnetic particles by reacting iron,cobalt,or nickel salts with phthalate ion in dialkyl sulfoxide Download PDF

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US3574683A
US3574683A US793196*A US3574683DA US3574683A US 3574683 A US3574683 A US 3574683A US 3574683D A US3574683D A US 3574683DA US 3574683 A US3574683 A US 3574683A
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phthalate
magnetic
cobalt
metal
bath
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Harold Kenneth Johnston
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International Business Machines Corp
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International Business Machines Corp
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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
    • H01F1/063—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 non magnetic core
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
    • E21D11/04—Lining with building materials
    • E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
    • E21D11/105—Transport or application of concrete specially adapted for the lining of tunnels or galleries ; Backfilling the space between main building element and the surrounding rock, e.g. with concrete
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/62—Record carriers characterised by the selection of the material
    • G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
    • G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
    • G11B5/706—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material
    • 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
    • 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
    • H01F1/065—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 obtained by a reduction

Definitions

  • This invention relates to the manufacture of fine magnetic particles suitable for use in magnetic recording media, permanent magnets, magnetic cores, and in magnetically responsive fluid suspensions, such as magnetic or electrostrictive clutch coupling and the like.
  • the invention relates to a method of making fine magnetic metal, alloy, or oxide particles by dissolving a metal salt of nickel, cobalt, iron, or mixtures of these salts in a dialkyl sulfoxide bath (preferably dimethyl sulfoxide); reacting the metal salt with phthalate ion which is dissolved in the dialkyl sulfoxide bath; precipitating the metal phthalate reaction product by adding water to the bath; separating the precipitate; and decomposing the precipitate, either by heating in an oxidizing atmosphere at 100-450" C.
  • a dialkyl sulfoxide bath preferably dimethyl sulfoxide
  • the ultrasonic field may be formed by commercially available devices, such as the Rapisonic ultrasonic device sold by Sonic Engineering Corporation, Stamford, Conn., which vibrates a blade at a frequency of 22K c.p.s., or by piezoelectric crystal transducers (e.g., quartz, barium titanate, and the like which convert electric energy into ultrasonic waves between 10K c.p.s. and 1M c.p.s.), or by other transducers which are described in the literaice ture.
  • piezoelectric crystal transducers e.g., quartz, barium titanate, and the like which convert electric energy into ultrasonic waves between 10K c.p.s. and 1M c.p.s.
  • Low intensities of the order of .01-0.7 watt per square centimeter of ultrasonic energy are generally adequate to disperse the precipitate and prevent particle agglomeration by vibrational motion in the dialkyl sulfoxide bath.
  • the phthalate ion may conveniently be provided from monobasic soluble salts of phthalic acid, such as sodium acid phthalate, potassium acid phthalate, ammonium acid phthalate; from soluble dibasic salts of phthalic acid, such as disodium phthalate, dipotassium phthalate, diammonium phthalate; from phthalic anhydride; or from phthalic acid.
  • monobasic soluble salts of phthalic acid such as sodium acid phthalate, potassium acid phthalate, ammonium acid phthalate
  • soluble dibasic salts of phthalic acid such as disodium phthalate, dipotassium phthalate, diammonium phthalate
  • phthalic anhydride or from phthalic acid.
  • Any soluble salt of iron, cobalt, or nickel may be used, and the chlorides, nitrates, sulfates, and acetates are representative salts which are readily available and have been used with good results.
  • a dilute solution of a metal salt in a dialkyl sulfoxide bath and to add the phthalate to it in diluted form, also in dialkyl sulfoxide.
  • fractional molar quantities are mixed by preparing separate solutions of salt in dialkyl sulfoxide and of phthalate ion in dialkyl sulfoxide.
  • an essential feature of the method of the present invention is the dialkyl sulfoxide bath as the medium for dissolving the metal salt and phthalate ion in the sequence of first dissolving and then precipitating the metal phthalate by adding water.
  • dimethyl sulfoxide is the preferred dialkyl sulfoxide, but diethyl sulfoxide, dipropyl sulfoxide, dibutyl sulfoxide, and diisobutyl sulfoxide may be used.
  • Unsymmetrical sulfoxides may be used, such as methyl ethyl sulfoxide and methyl isobutyl sulfoxide.
  • Example 1A Criticality of dialkyl sulfoxide bath as the medium for reacting phthalate ion and metal salt in the absence of water Solutions of one-tenth molar C001 6H O and FeCl 4H O in water and in dimethyl sulfoxide were prepared.
  • a volume of dimethyl sulfoxide equal to that of the 0.1 molar ferrous chloride and 0.1 molar potassium acid phthalate was added to the aqueous mixture and no precipitation was observed.
  • Equal volumes of the above 0.1 molar ferrous chloride in dimethyl sulfoxide and 0.1 molar potassium acid phthalate in dimethyl sulfoxide were mixed. No precipitate was formed.
  • a volume of Water twice that of the volume of ferrous chloride and potassium acid phthalate solution was added and the solution was agitated manually, and the metal phthalate salt precipitated.
  • a mixture of equal parts by volume of 0.1 molar cobalt chloride in dimethyl sulfoxide and 0.1 molar ferrous chloride in dimethyl sulfoxide was reacted with an equal volume of 0.1 molar potassium acid phthalate salt and the co-crystallized cobalt-iron phthalates were precipitated by adding water in a volume equal to the volume of the reaction mixture.
  • the iron phthalate salt and the mixed iron-cobalt phthalate salt prepared above Were separated by filtration and the residue was washed with water and placed in an oxidizing atmosphere in a furnace at 400 C. for 3 hours. In each instance, all of the organic matter of the precipitate was removed and a finely divided magnetic oxide was obtained; e.g., iron oxide in the form of black gamma iron oxide, and black flakes of cobalt-modified oxide, respectively.
  • Example 1B.Effect of ultrasonic vibrations on diminishing size of resulting magnetic oxide and metal particles The precipitations in dimethyl sulfoxide of the two samples of salts as above (iron and iron-cobalt mixture) were repeated, using an 800 k.c. quartz piezoelectric transducer to provide an ultrasound field during the dilution-precipitation step.
  • the particle size ranged from 0.01 to 1.0 micron.
  • the average particle size of the iron particles was 0.03 micron, and the average particle size for the mixed ironcobalt particles was 0.04 micron.
  • Example 2.Effect of variations in concentration of metal salt solutions in dimethyl sulfoxide This example illustrates the doubling of the metal salt concentration from 0.1 molar to 0.2 molar. The beneficial results of this example are achieved with increasing concentrations as high as 0.9 molar. At higher concentrations, additional washing is necessary and control of uniformity of particle size is more difficult to maintain under conditions of normal manual agitation.
  • Example 1A In general, the same procedure was followed as in Example 1A above and 8 g. of FeCl .4H O were dissolved in 200 ml. of dimethyl sulfoxide to form a 0.2 molar solution. Eight g. of potassium acid phthalate were dissolved in 200 ml. of dimethyl sulfoxide to form a 0.2 molar solution. These solutions were mixed and no reaction occurred. 300 ml. of distilled water was added, causing precipitate to form which was allowed to settle overnight. The supernatant liquid was siphoned off and the precipitate washed with 1000 ml. of distilled water. This washing procedure was repeated six times and the precipitate was then removed by centrifuging, dried at 100 C. for 54 hours, and then reduced in a nickel boat under hydrogen at 400 C. for 2 hours. The metal particles recovered were cubic in form, varied in particle size between 0.01 and 0.1 micron, and had an average particle size of 0.03 micron.
  • VSM Vibrating Sample Magnetometer
  • Example 3 Preparation of mixed cobalt-iron magnetic particles
  • a 0.2 molar solution of mixed cobalt and iron salts was prepared by dissolving 9.6 g. of CoCl .6H O and 8.0 g. of FeCl- .4H O in 200 ml. of dimethyl sulfoxide.
  • a 0.2 molar phthalate solution was prepared by dissolving 12 g. of potassium acid phthalate in 300 ml. of dimethyl sulfoxide. The mixed salts in solution were added without reaction to the phthalate solution with efficient agitation, and 800 ml. of distilled water was then added to cause precipitation.
  • the precipitate was allowed to settle; the supernatant liquid was siphoned off; and the material was washed six times with distilled Water, 1000 ml. of distilled water being used in each washing. After the sixth washing, the wet concentrated water slurry was centrifuged and the precipitate was removed and dried at C. for 54 hours. The product was then put in a nickel boat, reduced at 400 C. under hydrogen for 2 hours, and cubic crystals of magnetic cobalt-iron in a particle size range of from 0.02 to 5.8 microns were produced. The average particle size was 1.5 microns.
  • Example 4 Preparation of mixed nickel-iron magnetic particles
  • a 0.2 molar solution of mixed nickel and iron salts was prepared by dissolving 9.6 g. of NiCl .6H O and 8 g. of FeCl AH O in 200 ml. of dimethyl sulfoxide.
  • a 0.2 molar solution of phthalate was prepared by dissolving 12 g. of potassium acid phthalate in 300 m1. of dimethyl sulfoxide.
  • the mixed salts in solution were added without reaction to the phthalate solution with efiicient agitation, and 800 ml. of distilled water was then added to cause precipitation.
  • the precipitate was allowed to settle; the supernatant liquid was siphoned off; and the material was washed six times with distilled water, 1000 ml. of distilled water being used in each washing. After the sixth washing, the wet concentrated water slurry was centrifuged and the precipitate was removed and dried at 100 C. for 54 hours. The product was then put in a nickel boat, reduced at 400 C. under hydrogen for 2 hours, and cubic crystals of magnetic nickel-iron in a particle size range of 0.01 to 0.5 micron were produced. The average particle size was 0.1 micron.
  • Example 5 Additional of powdered phthalic acid to dimethyl sulfoxide A 0.2 molar solution of mixed nickel and iron salts was prepared by dissolving 9.6 g. of NiCl .6H O and 8 g. of FeCI AH O in 200 ml. of dimethyl sulfoxide. 16 g. of powdered phthalic acid was added to the solution of nickel and iron salts in the dimethyl sulfoxide bath with agitation. No precipitate formed.
  • the average particle size was 0.04 micron.
  • Example 6-Preparation of 70% iron30% cobalt A 0.1 molar solution of 70:30 iron-cobalt was prepared by dissolving 6.73 g. FeCl .4H O and 3.27 g. of
  • Example 7 Preparation of 60% iron40% cobalt A 0.1 molar solution was prepared by dissolving 6.05 g. of FeCl .4H O and 4.59 g. of CoCl .6H O in 500 ml. of dimethyl sulfoxide. A 0.1 molar solution of phthalate ion was prepared-by dissolving 10.2 g. of potassium acid phthalate in 500 ml. of dimethyl sulfoxide. These 500 ml. solutions were mixed togeher without reaction and 1000 ml. of distilled water was added while agitating to cause precipitation. An additional 1000 ml. of distilled water was added to insure complete precipitation.
  • the precipitate was allowed to settle; the supernatant liquid was siphoned ofi; and the material was washed twice with distilled water, 1000 ml. of distilled water being used in each washing. After the second washing, the concentrated water slurry was centrifuged and the precipitate was removed. The product was heated at 400 C. 14 hours, whereby organic matter was eliminated and a magnetic cobalt modified iron oxide was produced. The magnetic oxide was reduced in a furnace at 260 C. with hydrogen for 2 hours to produce a magnetic alloy.
  • Example 8 Preparation of magnesium modified ironparticles with phthalic acid addition In 200 ml. of dimethyl sulfoxide, there were dissolved without reaction '16 g. of FeCl .4H O, 4 g. of
  • Example 10 Iron particles from ferrous sulfate and phthalic acid
  • diethyl sulfoxide there was added 8 g. of FeSO -7H O and 8 g. of phthalic acid and the solution was mixed for 45 minutes at room temperature without reaction.
  • the solution was diluted with 1000 ml. of distilled water to precipitate the insoluble iron salt which was washed twice with 1000 ml. portions of distilled water, centrifuged, dried at 100 C. overnight, and reduced with hydrogen at 400 C. for 2 hours, whereby cubic crystals of magnetic iron where recovered.
  • the gamma iron oxide or cobalt modified gamma iron oxide in acicul ar form obtained when the process as in Example 1A included an oxidation step, but no reduction step, may be used together with a film-forming binder.
  • Mixtures of iron-cobalt metal particles prepared in Example 1 may be used with a binder in the preparation of magnetic recording media, or the iron particles prepared in Example 2 may be used for sound recording tape and, similarly, the metal particles of the remaining examples are also useful in preparing various recording media; especially the iron-cobalt-nickel particles obtained by mixing the products of Examples 4 and 6.
  • binders for these various recording media are polyesters, cellulose esters and ethers, vinyl chloride, vinyl acetate, acrylate and styrene polymers and copolymers, polyurethanes, polyamides, aromatic polycarbonates (as, for example, those produced from 2,2 bis (4-hydroxyphenyl)propane), and polyphenyl ethers (as, for example, those produced by oxidative coupling of 2,6 dimethyl phenol).
  • a wide variety of solvents may be used for forming a dispersion of the fine particles and binders.
  • Organic solvents such as ethyl, butyl and amyl acetate, isopropyl alcohol, dioxane, acetone, methylisobutyl ketone, cyclohexanone, and toluene frequently are used for this purpose.
  • the particlebinder dispersion may be applied to a suitable substrate by roller coating, gravure coating, knife coating, extrusion or spraying of the mix onto the backing or by other known methods.
  • the specific choice of non-magnetic support, binder, solvent, or method of application of the paring magnetic record media such as video tapes, computer tapes, and sound tapes.
  • the magnetic particles comprise about 40-90% by weight of the film layer applied to the substrate.
  • the substrate is usually a paper, polyester, or cellulose acetate material, although rigid base material of plastic or metal is more suitable for some uses.
  • the products of the foregoing examples are mixed with non-magnetic plastic or filler in an amount of 33 to 50% by volume of the finished magnetic metal, the particles aligned in a magnetic field, and the mixture pressed into a firm magnet structure. Alignment of the particles may be accomplished in an externally applied D.C. magnetic tfield of about 4000 gauss or more, and fields up to 28000 gauss may be used. Pressures may vary widely in forming the magnet, and pressures up to 100,- 000 p.s.i. have been used commercially.
  • the magnetic particles prepared in accordance with the invention may be mixed with hydrocarbon mineral oil or with other liquids as disclosed in Winslow, US. Pat. 2,417,850, and Rabinow, US. Pat. 2,575,360.
  • the oil-diluted magnetic composition responds to a magnetic field and is useful in power couplings and clutches.
  • a method for manufacturing magnetic particles comprising:
  • dissolving salt including a metal salt of nickel, cobalt,
  • a method for manufacturing magnetic oxide particles comprising:
  • dissolving salt including a metal salt of nickel, cobalt,
  • dialkyl sulfoxide bath consists essentially of dimethyl sulfoxide.
  • a method of manufacturing magnetic recording media comprising:
  • dissolving salt including a metal salt of nickel, cobalt,
  • a method of manufacturing magnetic recording media comprising:
  • dissolving salt including a metal salt of nickel, cobalt,

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Structural Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Architecture (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Civil Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Inks, Pencil-Leads, Or Crayons (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
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  • Hard Magnetic Materials (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
US793196*A 1969-01-14 1969-01-14 Preparation of magnetic particles by reacting iron,cobalt,or nickel salts with phthalate ion in dialkyl sulfoxide Expired - Lifetime US3574683A (en)

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FR (1) FR2028252A1 (enrdf_load_stackoverflow)
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3970738A (en) * 1974-07-15 1976-07-20 Toda Kogyo Corporation Process for producing iron oxide products from waste liquids containing ferrous salts
US4059716A (en) * 1974-06-14 1977-11-22 Basf Aktiengesellschaft Manufacture of gamma-iron(III) oxide
US4069367A (en) * 1972-01-13 1978-01-17 Tdk Electronics Company, Limited Magnetic powder material comprising iron oxide particles with a copper-cobalt alloy coating
US4170602A (en) * 1973-09-28 1979-10-09 Graham Magnetics, Inc. Method of producing acicular metal crystal
US4262037A (en) * 1976-04-05 1981-04-14 Hitachi, Ltd. Method of producing ferromagnetic metal powder
US5456734A (en) * 1993-05-07 1995-10-10 Fuji Photo Film Co., Ltd. Abrasive member
US6517802B1 (en) * 1996-11-18 2003-02-11 The University Of Connecticut Methods of synthesis for nanostructured oxides and hydroxides
EP0865511B2 (en) † 1995-12-08 2003-03-05 Umicore Pre-alloyed powder and its use in the manufacture of diamond tools
CN114318003A (zh) * 2021-12-22 2022-04-12 安阳师范学院 一种强化萃取分离钴镍离子的方法

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4069367A (en) * 1972-01-13 1978-01-17 Tdk Electronics Company, Limited Magnetic powder material comprising iron oxide particles with a copper-cobalt alloy coating
US4170602A (en) * 1973-09-28 1979-10-09 Graham Magnetics, Inc. Method of producing acicular metal crystal
US4059716A (en) * 1974-06-14 1977-11-22 Basf Aktiengesellschaft Manufacture of gamma-iron(III) oxide
US3970738A (en) * 1974-07-15 1976-07-20 Toda Kogyo Corporation Process for producing iron oxide products from waste liquids containing ferrous salts
US4262037A (en) * 1976-04-05 1981-04-14 Hitachi, Ltd. Method of producing ferromagnetic metal powder
US5456734A (en) * 1993-05-07 1995-10-10 Fuji Photo Film Co., Ltd. Abrasive member
EP0865511B2 (en) † 1995-12-08 2003-03-05 Umicore Pre-alloyed powder and its use in the manufacture of diamond tools
US6517802B1 (en) * 1996-11-18 2003-02-11 The University Of Connecticut Methods of synthesis for nanostructured oxides and hydroxides
CN114318003A (zh) * 2021-12-22 2022-04-12 安阳师范学院 一种强化萃取分离钴镍离子的方法

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GB1267263A (enrdf_load_stackoverflow) 1972-03-15
FR2028252A1 (enrdf_load_stackoverflow) 1970-10-09

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