hectograph
OAB Definition
print made by introducing an aniline-dye master made to a gelatin slab, then placing a sheet of paper on the slab to pull a copy. Up to a hundred copies can be made, in the right circumstance, before needing to clean the slab and reintroduce the master.
Before the introduction of photo copiers, hectographs were widely used for small scale reproduction and publication along with other methods such as mimeography.
Other inks and pigments can be used for a hectograph master, but they may produce fewer consecutive copies.