Hard, glazed rollers on a press impede print quality on all offset lithographic presses. As a general rule, soft rollers print better than hard rollers. Hard rollers will cause more streaking, give more color variation, and in many cases, increase mechanical ghosting on a press. In a three shift operation, general dampening rollers will usually last 3-6 months and ink rollers about one year. In a single shift plant, the figures are approximately one year for dampening rollers and 3 years for ink rollers. Rollers should be changed when they are hard, cannot be stripped properly, or when they are pitted or uneven.
Naturally, the above figures only apply when good care is applied. Ink roller maintenance includes:
* Use of approved roller wash and water to clean rollers
* Use of hot water and 15% vinegar to rinse rollers for calcium deposits
* Use of a deglazing/cleaner paste that is applied overnight or on weekends