The primary function of solution is to desensitize the nonimage areas of the printing plate to ink. A surface that is "desensitized to ink" is a surface that ink will not adhere to. An area sensitized to ink will accept ink readily. The dampening solution also helps to keep the plate, rollers, and blanket cool and washes away much of the dirt and debris on the plate or blanket, which might otherwise build up as a kind of surface crust known as piling. The dampening solution is also absorbed into the ink on the form rollers. reducing the tack (or stickiness) of the ink film. This is important because it reduces the chance of surface fibers or previously printed ink films from being pulled from the press sheet, a problem known as picking. However, the dampening solution must not excessively emulsify the ink or prevent proper ink drying. The dampening system may also help to reduce static problems that can occur in the delivery end of the press.
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