Patent ID: 6059398
Filing Date: 2000-05-09
Classification: B41J

Abstract:
A device for direct electrostatic printing on an image-receiving substrate, comprising:a surface carrying dry charged toner particles and coupled to a voltage source creating a flow of charged toner particles away from said surface towards said image-receiving substrate; anda printhead structure placed in said flow between said surface carrying toner particles and said substrate, said printhead structure comprising:(i) an insulating material having first and second sides; and(ii) printing apertures in said insulating material extending from said first side to said second side, each printing aperture having a long dimension A measured on said second side and a long dimension D measured on said first side,(iii) wherein said first side carries a control electrode associated with each said printing aperture and said second side carries a common shield electrode;(iv) and wherein:said shield electrode has openings associated with said printing apertures, each said shield electrode opening having a dimension B measured parallel to said dimension A;each of said control electrodes has an opening associated with one of said printing apertures, each said control electrode opening being substantially centered on said associated printing aperture and having a dimension E measured parallel to said dimension D; andB/A.gtoreq.1.1 and E.gtoreq.D.