21.09.2020 TKM
Ghosting (flexography)
The paint collects around the closing doctor blade and its surroundings. Due to its design, the doctor blade is subjected to dynamic pressure because the lamella surface lies within the chamber and bends inwards. If the doctor blade is too stiff, or if there is too much pressure on the chamber, this prevents the remaining ink from flowing back into the chamber. A build-up of ink on the outside of the chamber is the result.
Solutions to ghosting:
- Check the anilox rollers' geometry and select a different roller if necessary.
- Quick-drying ink can clog the cells, air streams should not be blown onto the anilox roller.
- Examine the contact pressure of the docotr blade chamber and readjust if necessary to reduce friction and prevent ink shearing off due to frictional heat.
- Increase filling pressure of the ink in the ink chamber.
- Select a working squeegee with a larger contact zone
- Perform deep cleaning of the anilox roller
TKM recommends periodic deep cleaning with TKM enpurex, the use of TKM OptiPrint and TKM PowerPrint.