A ductor roller or form roller in a conventional dampening system on an offset press used without fabric or paper covers, allowing the fountain solution to transfer directly to its rubber-compound surface. Rollers that are run bareback respond more quickly to changes made to the amount of fountain solution sent to the plate. A wetting agent such as alcohol is needed to reduce the surface tension of the solution, allowing the fluid to form a continuous film more easily in the absence of an absorbent cover. (See Dampening System.)
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