Premagnetizing Magnetic Data Carriers
Original Publication Date: 1985-Oct-01
Included in the Prior Art Database: 2005-Feb-19
Before impinging upon the substrate to be coated, the magnetic particles, of, say, qFe2O3, which are used to form the magnetic layer during the production of magnetic information carriers, are forced into the preferred direction by a suitable magnetic field. During their travel from spray valve SpV to substrate surface SuS, magnetic particles MP are subject to an external magnetic field HH, HV by which their magnetic moment is aligned relative thereto. Thus, particles MP assume the desired premagnetization direction before impinging upon the substrate, maintaining that direction during their entire travel within spray cone SpC and retaining it even after they have reached substrate surface SuS. During spray coating, the substrate moves at a constant speed underneath spray valve SpV.