Causes for ghosting
This problem happens often with doctor blade chamber systems and in running direction of the substrate. More prone in certain colors, the root cause is often the choice of the wrong anilox role. The anilox roll can not collect enough ink and pass that on to the printing plate. Another root cause is the bad synchronization between anilox roll and printing plate. The ink quantity differs with every rotation as some cells are overfilled while other be left underfilled. One should select an anilox geometry which can collect enough in to prevent ghosting.
Solutions for ghosting
1. Please check your anilox geometry, if necessary please select a different anilox roll.
2. Drying ink can plug the cells, please avoid air blown onto the anilox roll.
3. Please check the doctor blade chamber and if necessary adjust in order to improve friction and avoid ink shearing due to heat.
4. Increase ink pressure inside the doctor blade chamber.
5. Check doctor blade type and increase tip size
6. Deep clean the anilox roll to avoid dirty cells.
TKM recommends periodical deep cleaning of the anilox roll with TKM enpurex, use TKM OptiPrint and TKM PowerPrint.