A printing defect, commonly found in flexographic and gravure printing processes (and occasionally in screen printing), 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 can frequently overcome the problem of pinholing. In gravure printing, pinholing can also be caused by the presence of air bubbles in the ink which transfer to the cells and print as voids. In flexography, there are two varieties of pinholing: chemical pinholing and mechanical pinholing.
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