blocking

n.The use of a machine to make a mark by pressing a die, plate, or frame against a surface.Preservation and ConservationThe condition in which materials, especially photographic film and magnetic tape, adhere to adjacent materials or to itself, if in a reel or layers, usually as the result of poor storage conditions.

Notes

Blocking1 is distinguished from stamping, the latter being done by hand. - Blocking2 is distinguished from ferrotyping, where materials of different types adhere, such as a framed photographic print being ferrotyped to the glass.