Study of print contrast and dot gain on gloss coated paper printed by liquid toner and dry toner electrophotography process.

Electrophotography is a process of digital printing in which master is stored and processed as a digital file. This process was invented by Chester Floyd Carlson who was an American physicist. Various developments in this process have resulted in improved print quality. Depending upon the type of toner used, Electrophotography can be classified into two types: 1) Liquid Toner Electrophotography 2) Dry Toner Electrophotography. Toner particle size of Dry Toner Electrophotography is equal to or larger than 5 µm and that of Liquid Toner Electrophotography is equal to or smaller than 2 µm. This study was conducted to analyze the print quality of Liquid Toner and Dry Toner Electrophotography process on the basis of Print Contrast and Dot Gain. Good Print Contrast represent good details in the shadow area. Low Dot Gain helps in controlling unintentional density increase resulting in reproduction of halftone details appropriately. This study was conducted on presses using Liquid Toner and Dry Toner Electrophotography Technology for generating prints. HP Indigo 5600 was used for Liquid Toner Electrophotography prints and Xerox Versant 2100 was used for Dry Toner Electrophotography prints. Prints were taken on Gloss Coated Paper having grammage of 200 GSM. Total 100 (50 each) sheets were printed using both technologies. X-rite exact Spectrophotometer was used for analyzing the results. For this study, Print Contrast is measured at 80 % tonal value and Dot Gain is measured at 50 % tonal value. Results of this study shows that Print Contrast of Cyan, Magenta and Yellow color is lesser and that of Black color is higher for the samples printed by Liquid Toner Electrophotography. Dot Gain of Magenta and Black Color is lower and that of Cyan and Yellow color is similar for the samples printed by Liquid Toner Electrophotography. Consistency of Print Contrast and Dot Gain is higher for the samples printed by Liquid Toner Electrophotography. [ABSTRACT FROM AUTHOR]