Study on Magnetic Force Acting on the Magnetic Toner in the High Pixel Density Magnetic Printer With Longitudinal Recording

Abstract

The purpose of this study is to realize much higher pixel density such as 2,000dpi than the current available magnetic printer of 600dpi. In the magnetic printer with longitudinal recording method, if the adjoining magnetic charges become near, self-demagnetizing field increases which decreases magnetization of the recording medium in turn. The higher the pixel density becomes, the weaker the magnetic force acting on the magnetic toner becomes. The magnetic forces acting on the magnetic toner are calculated with various characteristics of the recording medium and the toner. The analysis is effected from the view point of the magnetic force enough to attract the magnetic toner. The suitable combinations of the characteristics of the recording medium and the toner are discussed. The results are as follows. a) As the pixel density increases, the magnetic force decreases exponentially; b) At 2,000dpi the magnetic force becomes 1/10 of that of 400dpi. c) Even at 2,000dpi there exist some conditions which can generate the same magnetic force as that of 400dpi. d) One of the suitable condition is a combination of the recording medium with the residual magnetization of 0.8Wb/m2, the coercive force of 64kA/m and the thickness of 0.37μm and the magnetic toner with the diameter of 5μm and the relative magnetic permeability of 2.