Magnetic material and production thereof
Abstract
Abstract PURPOSE: To obtain a magnetic material which has excellent dispersibility and magnetic characteristics and gives a magnetic film having excellent wear resistance, etc., by immersing a powdered magnetic material in an aq. soln. of a specified phosphate ester, filtering the material and drying it. CONSTITUTION: An aq. soln. of one member selected from phosphate monoester of formulaI, phosphate diester of formula II (wherein R is 4W24C alkyl, alkenyl, alkylphenyl; n is 0, 1W30; m is 1W30) and derivatives thereof, is prepd. A powdered magnetic material such as γ-Fe 2 O 3 or magnetite is immersed in the aq. soln., filtered and dried to obtain the desired magnetic material. The compds. of formulasI, II can be prepd. by addition-polymerizing propylene oxide or ethylene oxide and propylene oxide with a 4W24C alcohol or an alkylphenol and then seterifying the obtained addition polymer with phosphoric acid. COPYRIGHT: (C)1982,JPO&Japio
Inventors
- 👤 Yoshinobu Nakamura
- 👤 Isao Moriguchi
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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