Title :
Deposition of Sn hydrosols on Co-γ-Fe2O3 magnetic particles
Author :
Chen, W.-J. ; Tarng, M.R.
Author_Institution :
Mater. Res. Lab., Ind. Technol. Res. Inst., Hsinchu, Taiwan
fDate :
11/1/1991 12:00:00 AM
Abstract :
An improved colloidal solution of tin hydrous oxide has been developed. This solution was found to readily deposit onto the low-wettability surface of Co-γ-Fe2O3 particles to form a uniform layer of irremovable coating. Based upon the chemical characterization of the tin-sol-treated surface, the effectiveness of such treatments on magnetic oxide particles is described in terms of dispersion stability, dispersibility, rheological behavior, and other magnetic tape performance. A significant improvement in wetting, dispersion and flow behavior was observed for the 1% Sn coated magnetic particles upon dispersion in a polyurethane-based formulation. Additional magnetic tape data also revealed that surface treatments on magnetic particles facilitate the particle orientation by exposure to a 2000-Oe external magnetic field before dying, as evidenced by the high values of hysteresis squareness up to 0.8, indicating good dispersion of magnetic particles
Keywords :
X-ray chemical analysis; X-ray photoelectron spectra; cobalt; ferrites; iron compounds; magnetic fluids; magnetic hysteresis; magnetic properties of fine particles; magnetic recording; magnetic tapes; surface treatment; Fe2O3:Co; Sn hydrosols deposition; X-ray photoelectron spectroscopy; chemical characterization; colloidal solution; dispersibility; dispersion stability; energy dispersive X-ray spectroscopy; external magnetic field; flow behavior; hysteresis squareness; magnetic particles dispersion; magnetic pigment; magnetic recording; magnetic tape; particle orientation; rheological behavior; surface treatments; wetting; Chemicals; Coatings; Dispersion; Magnetic fields; Magnetic hysteresis; Magnetic particles; Rheology; Stability; Surface treatment; Tin;
Journal_Title :
Magnetics, IEEE Transactions on
