Magnetic Tapes for Contact Duplication by Anhysteretic and Thermal Transfer Methods

According to the increasing demands for magnetic tape printing especially for video tape, the magnetic tape duplication using a contact process is one of the most attractive solutions. There are two major methods, i. e. anhysteretic transfer and thermal transfer. The coercivity of the master tape should be 2.5 times higher than the slave by computer simulation for anhysteretic transfer, but is not important for thermal transfer. The highest coercivity of the slave tape will be decided by the master tape which, in turn, is limited by the recording head saturation for anhysteretic transfer, however, the thermal characteristics of coercivity and magnetic induction under Tc are more dominant for thermal transfer. The tape surface roughness as well as the coercivity is very important for short wavelength printing. In this paper, the properties of the master and slave tapes for anhysteretic and thermal transfer are discussed with theoretical and experimental results.