WET-TRAPPING OF ENERGY CURABLE FLEXOGRAPHIC INKS OR COATINGS

摘要

Methods and apparatus for flexographic color printing, and more particularly for implementing “wet trapping” in flexographic printing using energy curable flexographic liquid inks are presented. Radiation curable inks can be formulated that wet trap over each other without back-trapping onto the plates and anilox units of down-line printing units by controlling the storage modulus of the inklcoating. The storage modulus G′ in the inks can be controlled to ensure that the highest G′ ink is printed ISt down with successive colors being trapped in the order of their (declining) G′ values. An image in wet ink can thus be trapped over a different image in wet ink of a different color without picking the ISt ink back up and redepositing it onto the subsequent plates and rollers in the printing press (back-trapping).