bite

In letterpress and relief printing, a bite is a blank area on the printed sheet where ink failed to reach the paper. This happens when an obstruction sits between the type or printing surface and the paper during impression, preventing contact and transfer of ink. The result is a visible gap in the printed image, most often appearing at edges or corners where such obstacles are most likely to lodge.

The frisket, a sheet of paper or film adhered to the tympan (the packing beneath the platen), is the most common culprit. Friskets are cut away to expose only the areas that should print, but if the edges of the frisket curl or if a piece tears and lifts during the run, it can sit proud of the paper surface and cast a shadow. Debris, dried ink, or foreign matter trapped under the blanket can cause bites the same way. Even slight buildup of packing or a wrinkle in the underlay will do it.

Bites are particularly visible when they occur in solid areas or near the edges of type, where the viewer's eye catches the missing line. A bite along a frame border or in the corner of a justified block is immediately obvious. In fine printing and jobwork where registration and quality matter, even small bites are unacceptable and require investigation before the job can be approved for binding.

Prevention centres on maintaining the frisket carefully, inspecting the tympan and blanket for debris before each impression, and adjusting packing height so that no part of it sits above the paper surface. Pressmen check the first few sheets closely for bites before committing to a full run. If bites appear mid-run, the press must be stopped to locate and remove the obstruction.

The term reflects the visual character of the fault: the printing has taken a bite out of the image, leaving a void. It is distinct from hickeys (spots caused by debris sticking to the type) or slurring (movement of type during impression). A bite is silent evidence of a physical block between inked surface and substrate.