Toner supply roll including porous cylindrical polyurethane sponge structure having skin layer having openings and alternate protrusions and recesses, and method of producing the same

Granted: Nov 21, 2000 Filed: Jul 15, 1998

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.