Printing With Superparamagnetic Fluids.

The basic principles of ferrofluidic technology and the utilization of superparamagnetic fluids in printing processes are discussed. Magnetic inks having an aqueous base, hydrocarbon base, or other special carriers have low viscosity and are totally stable against settling and/or separating. Superparamagnetic fluids incorporate magnetic particles of only 100 A in diameter, thus able to pass through the tiniest orifices The stability of these particles allows their use in impregnated ink rollers for computer line printers and high speed cylindrical presses printing with magnetic inks.