Negative doctor blade lines (gravure print)

Relatively continuous defects in the printed area, which affect individual rows of cells and always occur in the direction of printing. These streaks do not necessarily have to move with the doctor blade oscillation. Often foreign particles trapped under the doctor blades' bevel are responsible for this.

Solutions to negative doctor blade lines:

• Check the colour for dirt and foreign particles, replace clogged filters and replace colour if necessary.
• Carefully polish the impression cylinder with fine sandpaper, fold down the doctor blade holder and remove the doctor blade bevel with a cloth and solvent.
• Check and readjust the doctor blades' angle.