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Producing Magnetic Tape

IP.com Disclosure Number: IPCOM000092409D
Original Publication Date: 1966-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Judge, JS: AUTHOR [+3]

Abstract

Radio frequency heating is used to disperse and orient magnetic particles in a binder matrix. Application of the RF with a wavelength equivalent to the magnetic particle size or the average particle size causes the particles to align themselves with the field. Thus the particles are oriented in accordance with the direction of the RF field.

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Producing Magnetic Tape

Radio frequency heating is used to disperse and orient magnetic particles in a binder matrix. Application of the RF with a wavelength equivalent to the magnetic particle size or the average particle size causes the particles to align themselves with the field. Thus the particles are oriented in accordance with the direction of the RF field.

RF treatment is also used advantageously during dispersion of magnetic particles in a binder. The radio frequency is adjusted to cause the particles to flip with the changing field. This particle movement results in improved dispersion. In thermoplastic binders the heat generated in the particles by RF also allows them to move with increased ease through the binder during dispersion. Particles can be heated to their Curie point by application of the correct RF. On reaching the Curie point the magnetostatic force between particles is eliminated. As this force normally tends to hinder dispersion, its removal by the application of RF allows for improved dispersion.

These RF techniques are useful with both metallic and oxide types of magnetic materials. RF affects only the particles and not the binder, thus allowing localized high temperatures. The ability to generate heat in the particles, without directly heating the binder, makes possible the use of RF to dry elastomeric binders and to cure thermosetting binders from within.

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