What's happening here is that the ink is emulsifying into the water instead of the water emulsifying with the ink. As a result the ink is working its way into the water system from the form cover to the chrome oscillator. Factors that can cause this problem include the type of fountain solution, the source of the water used in the fountain mix, the type of ink, and the paper being printed. Sometimes the operator may be running the job with too much ink.
Additionally, the culprit is often the metering roller itself. If the surface of the chrome roller becomes "sensitized" by grease or oil it will begin to attract ink.
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