The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 09, 1999
Filed:
Jun. 03, 1997
Agfa-Gevaert, Mortsel, BE;
Abstract
A method for printing information on a substrate having security features includes the steps of: applying a DC potential difference (DC.sub.TB) between a back electrode and a toner delivery means to create a flow of toner particles from the toner delivery means to the back electrode; interposing a printhead structure, the printhead structure having printing apertures and control electrodes around the printing apertures, between the toner delivery means and the back electrode so as to create a spacing having a width L between the printhead structure and the back electrode and to imagewise control the flow of toner particles; passing the substrate having a thickness T in .mu.m through the spacing; adjusting the spacing between the printhead structure and the back electrode such that the width of the spacing L is greater than or equal to 1.5 T; adjusting the DC potential difference (DC.sub.TB) such that the relationship .vertline.DC.sub.TB .vertline./L, expressed in volts per micrometer (V/.mu.m), is greater than or equal to 1.0; imagewise depositing the toner particles on the substrate through the printing apertures; and fixing the toner particles to the substrate.