Method of producing a perforated metal foil

摘要

To produce a perforated metal foil, especially for use in a screen printer, a decomposable, dissoluble or vaporizable dielectric substance is deposited on a cylindrical conductive substrate in a dot pattern under the control of a photoelectrically scanned master. The spaces between the dots are then filled with an electrolytically deposited metal forming a coherent layer which is subsequently stripped off the substrate. The deposition of the dot pattern is carried out through a spray nozzle, sweeping the rotating substrate, which has an outlet in a bottom wall of a narrow space filled with the liquid dielectric to be dispensed, that space being separated by an apertured partition from an overlying plenum chamber in which the air is intermittently pressurized by an electromagnetic armature to expel a limited quantity of dielectric through the outlet; the membrane may be vibrated at supersonic frequencies to generate the necessary discharge pressure.