Media/Toner Interactions in Laser Printing

Abstract

According to CAP Ventures, monochrome Print-on-Demand (POD) book publishing is currently a 10 bn industry growing at a rate of 10% each year. Such POD and other electro-photographic applications demand an exceptionally high degree of print resolution as well as good toner adhesion. Controlled particle size distribution of the toners, higher print speeds, and other advances in color laser printing are also placing special demands on the media used for printing. This paper attempts to separate the effects of three different fuser roll cover materials, which impact the nip dynamics, to the print resolution and uniformity as well as the toner adhesion to the substrate. The toner adhesion was characterized by Scanning Electron Micrographs (SEM's). A model has been developed to estimate nip residence time for the fuser roll covers. As shown in the model, this parameter can be affected both by roll cover design as well as print speed. In this limited study where the print speed was held constant and the nip residence time changed only due to roll cover design, it was shown to correlate well with print resolution as measured by image analysis techniques.