Abstract
Advancements in magnetic media technology for audio and video tapes have been made possible by investigating the fundamental mechanisms and properties of magnetic dispersions and coatings. In this study, development of magnetic dispersions required novel and quick methods for determining the degree of dispersion during milling in the liquid state since magnetic dispersions degenerate by agglomeration within minutes. Improved formulations were developed by observing compatibility of resins and solvents with acicular magnetic iron oxide powders and results were interpreted in rheological terms for the liquid dispersions since rapid feedback of information was possible. Coatings were characterized by surface gloss, x-ray radiography, optical and electron microscopy together with magnetic measurements. Results show that viscometric trends, degree of dispersion and magnetic properties are interrelated, and that capillary viscometry flow data provide the most consistent method of monitoring the “goodness” of the liquid dispersion before the coating is applied to uniaxially oriented polyester tape.
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© 1989 Plenum Press, New York
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Gooch, J.W. (1989). Rheological Characterization Of High Solids Magnetic Dispersions. In: Mittal, K.L. (eds) Polymers in Information Storage Technology. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-0843-0_20
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DOI: https://doi.org/10.1007/978-1-4613-0843-0_20
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4612-8110-8
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