Printing and paper defect caused by the mechanical stress of thick offset printing ink and the blanket pulling on a paper surface. As a paper is peeled from the blanket in offset printing, the force of the ink stretches heavily-printed areas past their ability to retain their original dimensions. (See Dimensional Stability and Visoelasticity.) Also called "embossing," waffling is characterized by embossed bands in heavily printed areas, where the pull of the ink in these regions has stretched the paper excessively, causing it to curl in these regions. Using paper that has high strength in its cross-grain direction or using a higher basis weight paper are ways of avoiding waffling. Waffling is rarely a problem in web offset printing. Waffling that occurs toward the rear edge of the paper is called back-edge curl or tail-end hook. (See Back-Edge Curl.)
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