Theoretical analysis of contact printing on magnetic tape

The magnetization process in contact printing is considered to be the same process as an ideal anhysteretic magnetization process. In the anhysteretic magnetization process a self-demagnetization effect by an internal field is an important factor, especially at short wavelength. Therefore, the internal field effect should be evaluated dynamically depending on the instantaneous strength of the diminishing bias field. It was shown that such an anhysteretic magnetization process including the internal field effect can be represented as a first-order feedback system in an automatic control theory. Thus the numerical analyzing method for the anhysteretic magnetization was established, and excellent coincidence between the numerically computed result and the experimental result in the contact printing was obtained. Consequently the distribution patterns of the magnetization and the internal field in the duplicated tape was computed.