Thermal ink jet printhead protective layers
US5448273A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1993 |
| Grant date | Sep 5, 1995 |
| Priority date | — |
| Expiry date | Jun 22, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12951
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
In a thermal ink jet printhead with a protective layer, the protective layer is made of a thin film material having a melting point not less than about 1000.degree. C. A deposition process for preparing the thin film material produces a thin film material having, at an operating temperature for the thermal ink jet printer, a thermal conductivity coefficient not less than about 10 W/m.K, a compressive yield strength not less than about 1400 MPa, and a compressive residual stress of not greater than about 1200 MPa. The protective layer is smooth, substantially free of pores and impervious to stress corrosion or hydrogen stress cracking at a hydrogen uptake rate of less than about 5 ppm. The protective layer may also contain an adhesion enhancing region between the protective layer and an underlying layer or an anodic region contiguous with an underlying thin film material of the protective layer. The adhesion enhancing region is a reaction product between an ambient gas and the thin film material of the protective layer and extends only to the grain boundaries of the protective layer. The contiguous anodic region is substantially free of pores, has a homogeneous composition, protects…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.