A printing defect, commonly found in the flexographic printing of waterproof cellophane and other non-absorbent substrates, characterized by an incomplete ink film comprising small holes, caused by the failure of an ink to wet the entire surface of the substrate. The use of additives, called anti-pinhole agents, can frequently overcome the problem of pinholing, typically by reducing the surface tension of the liquid ink. (See also Mechanical Pinholing.)
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