Elimination of water from printing ink - by passing thin film of ink through a high frequency electromagnetic field

摘要

Printing ink is pumped from an ink well to a nozzle. This nozzle sprays the ink in a thin film vertically downwards through a heating chamber. At the bottom of the chamber the ink is collected in a sump and pumped back to the well. A tube positioned perpendicularly to the thin film in the heating chamber emits a high frequency electro-magnetic field across the area through which the ink is sprayed. This field heats the ink by dielectric losses and the water in the ink evaporates. A fan removes the water vapour from the heating chamber. The chamber is lined with a material that absorbs the hyperfrequency radiation given off by the tube. Device is partic. useful on offset print machines, bit also for removing water from other cpds., e.g. alcohols. Water is eliminated without destroying the composition of the printing ink by parallel entraining of certain volatile constituents of the ink.