Any printing defect caused by a particle either of paper or other source of debris attaching itself to the printing plate, blanket, gravure cylinder, or other image-carrying surface. Debris produces either a blank, unprinted spot in a printed area (a void hickey) or a solid printed area ringed by a blank unprinted area (a doughnut hickey). The type of hickey produced depends on the ink receptivity of the particle; ink-repellent particles such as loose paper fibers rid themselves of ink on the plate or blanket and print as void hickeys; ink-absorbent particles pick up the ink and print as spots, but being raised particles, they do not allow the surrounding area to print and manifest themselves as doughnut hickeys. Doughnut hickeys produced by particles of ink skin collecting on the blanket or plate are called ink hickeys. (See Doughnut Hickey and Void Hickey.) Offset presses can also add a special roller, called a hickey-picking roller, which can either remove or lessen the effects of hickeys.
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