Ribbon configuration for resistive ribbon thermal transfer printing

Abstract

A resistive ribbon thermal transfer printing apparatus has an improved ribbon configuration. The ribbon contains a two-ply resistive element positioned on a conductive layer. The resistive element contains a top layer having a low resistance, for example 3.times.10.sup.-5 .OMEGA. for making contact with the writing head and a bottom layer having a higher resistance, for example 1.times.10.sup.-3 .OMEGA. in contact with the conductive layer for generating heat. The ratio of the resistance of the high resistance layer to the resistance of the low resistance layer, R.sub.H /R.sub.L, is 1.1 to 1000. An example of such a ribbon contains a top resistive layer of polyimide containing 35% conductive carbon, a bottom resistive layer of a SiO/Cr cermet (60%/40%), a stainless steel conductive layer and a Versamid ink layer.

Dependencies are inferred from the claim text.