Preparation of magnetic particles by reacting iron,cobalt,or nickel salts with phthalate ion in dialkyl sulfoxide
Abstract
Abstract A METHOD FOR PREPARING FINELY DIVIDED MAGNETIC METAL PARTICLES BY DISSOLVING A METAL SALT OF NICKEL, COBALT, IRON, OR MIXTURES OF THESE IN A DIALKYL SULFOXIDE BATH, PREFERABLY DIMETHYL SULFOXIDE; REACTING WITH PHTHALATE ION IN SAID BATH; PRECIPITATING THE METAL PHTHALATE REACTION PRODUCT BY ADDING WATER TO THE BATH; SEPARATING THE PRECIPITATE; HEATING AND REDUCING WITH HYDROGEN AT ELEVATED TEMPERATURES TO PRODUCE METALLIC PARTICLES OF CUBIC STRUCTURE IN A FINE PARTICLE SIZE RANGE OF ABOUT .01 MICRON TO ABOUT 7 MICRONS, WHICH ARE USEFUL IN MAGNETIC RECORDING MEDIA AND FOR PREPARING PERMANENT MAGNETS, MAGNETIC CORES, AND MAGNETICALLY RESPONSIVE FLUID COMPOSITIONS AS ARE EMPLOYED IN MAGNETIC CLUTCHES AND THE LIKE. PRECIPITATION OF THE METAL PHTHALATE IS NOT ACHIEVED IF AQUEOUS SOLUTIONS OF METAL SALT AND PHTHALATE ION ARE MIXED AND DIALKYL SULFOXIDE IS ADDED THEREAFTER.
Inventors
- 👤 Harold Kenneth Johnston
Bibliographic Details
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