My ink rollers are not carrying the ink evenly; there are areas with little ink on the roller surface. The problem seems worse on the rollers near the plate cylinder. Why is this happening and how can I correct the problem?
Mar 28, 2019

This condition sounds like roller stripping. Roller stripping can look like the ink is in bands on the rollers. Basically some of the gum in the dampening solution is being carried on the surface of the ink rollers, attracting the fountain solution and repelling the ink. There are many conditions that can cause roller stripping: most common are glazed rollers and calcium buildup from the paper. Other causes are over emulsified ink, poor ink water balance, and too much acid or gum in the fountain solution. I suggest you deglaze the rollers with a deglazing compound and replace old, hard rollers that can't be rejuvenated. Also, correct any ink water balance problems, check fountain solution pH and conductivity, and make sure that fountain solution concentrate or gum was mixed in the correct proportions.

Equipment Press

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