Faulty or improperly set ink or dampening rollers are wearing the plate
Check rollers for condition and settings
Foreign particles are entering into the ink train
Check paper, ink, solutions and overhead structures for foreign materials that may be dropping onto press
Plate cleaners or scratch removers have not been completely rinsed from the plate
Avoid excessive amounts of plate cleaner and scratch remover. Rinse plates thoroughly afterwards Be sure all water, sponges, rags, etc., that come in contact with the plate are clean. Do not let cleaners dry on the plate
Blanket is over-packed or loose
Check packing or blanket tension. Set to manufacturer’s specifications
Fountain solution may be out of balance
Check pH, conductivity, Brix level, and temperature. Ensure pan temperature is close to 65°F (18°C) and solvent level is not too high
Stock is depositing filler, coating, or lint on the blanket affecting plates
Review dampening settings. Check pH and conductivity. Discuss alternatives with your paper supplier
Excessive calcium, gum and other material in roller train
Apply a calcium rinse or hot water/white vinegar (2:1) rinse
Plate has been improperly prepared
Review procedures for plate making process