Fundamental Study on Ink Mottling

Abstract

Effects of latex Tg, starch level in color recipe and interval time between coating and drying on offset print mottle were studied. Coating colors were coated by a SDTA pilot coater. Coated samples were printed by RI print tester and commercial sheet-fed offset press and print mottle tendencies were evaluated. Starch and latex contents at coated surface were measured and relationships between print mottle and the surface binder contents were discussed. Temperature at the coated surface during drying process was measured and the influence of latex film formability on print mottle was also discussed.