Back doctoring (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 back doctoring:

1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. Check the contact pressure of the doctor blade chamber. If the pressure is too high, adjust according to the machine's specifications.
                                             2. A too stiff doctor blade causes problems with flexibility. Change to a thinner, more flexible doctor blade.