Thermal ink jet printhead with improved heating elements
US4947193A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 1989 |
| Grant date | Aug 7, 1990 |
| Priority date | — |
| Expiry date | May 1, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2002/14379
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An improved thermal ink jet printhead has a plurality of heating elements in ink channels selectively addressable by electrical signals to eject ink droplets from nozzles located at one end of the ink channels on demand. The heating elements each have a passivated layer of resistive material that has non-uniform sheet resistance in a direction transverse to the direction of ink in the channels. The non-uniform sheet resistance provides a substantially uniform temperature across the width of the resistive layer, so that the power required to eject a droplet is reduced and the droplet size dependence on electrical signal energy is eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.