Direct electrostatic printing device (Dep) and printhead structure with low current flow between shield and control electrodes
US5889540A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1995 |
| Grant date | Mar 30, 1999 |
| Priority date | — |
| Expiry date | Dec 19, 2015 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/4155
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An apparatus for direct electrostatic printing includes a back electrode and a printhead structure having a plastic insulating layer and printing apertures arranged therein. Individual control electrodes are combined with the printing apertures on a first side of the insulating layer, and a shield electrode is combined with the printing apertures on a second side of the insulating layer. A toner delivery apparatus is also included for delivering a cloud of dry toner particles in the vicinity of the printing apertures. The printing apertures are constructed and arranged such that, when applying a potential difference of 200V between the shield electrode and each individual control electrode, a current of no more that 50 .mu.A flows from each individual control electrode to the corresponding shield electrode through the corresponding printing aperture. Methods for forming the printing apertures in such a printhead are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.