Ivana Bolanča Mirković

THE INFLUENCE OF INK CONCENTRATION AND LAYER THICKNESS ON YELLOW COLOUR REPRODUCTION IN LIQUID ELECTROPHOTOGRAPHY TONER

Original scientific paper In liquid toner electrophotography, colour gamut is often diminished in the yellow region leading to problems with photo quality prints. It is known that the concentration of pigment particles in the printing ink and its thickness when applied on a paper substrate decisively influence final print quality. Variation of these two parameters for the yellow process ink was performed by modifying the printing process of the electrophotographic printer HP Indigo S1000. Printed colour patches of ECI test chart were analysed colorimetrically and using image analysis approach. Two-way analysis of variance was implemented to statistically assess the obtained results. Both studied responses – colour gamut volume and area coverage of halftone dots – were found to be primarily influenced by the yellow ink layer thickness and much less by the ink concentration. Increase from one to two ink layers had a significantly stronger effect on each of the two responses when compared to an additional increase from two to three layers.