Several studies and investigations have been conducted to test the new Toray plate. The studies revealed that the new plate eliminated many of the problems that used to hinder the progress and development of the driographic plate system. The two major problems with this plate were short run lengths and toning in the non-image areas. This study investigates toning problems in negative working Toray plates. Toning is a term that refers to the non-image areas of the driographic plate that are accepting ink. Previous studies have shown that ink tack and flow do not affect toning in any way. However, printing speed, nip pressure, printing density and ink temperature were found to have some effect on toning. To investigate the effect that different percentages of oil in the ink has on toning in the non-image areas of Toray negative working plates, this study uses five ink samples, each containing a different percentage of oil, and measures with a densitometer the density of toning in the non-image areas. The hypothesis tested in this study states that the amount of toning in the non-image areas of negative Toray plates increases as the amount of oil contained in the ink increases. Upon analyzing the data collected, it was found that when using the special driographic ink no scumming occured. However, the hypothesis proved to stand true because it was found that a strong positive relationship exists between the amount of oil contained in the driographic ink and the amount of toning in the non-image areas of negative Toray plates
