US4038517A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Environmentally and wear protected glass substrate thin film thermal printheads
Assignee: Boeing North American Inc
•
Filing: 1976-04-02
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Granted: 1977-07-26
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Expires: 1996-04-02
Abstract
Abstract Glass-substrate thin film thermal printheads are protected from both chemical contamination and the mechanical wear by a coating comprising aluminum oxide (Al 2 O 3 ) over silicon monoxide (SiO) disposed on the printhead.
Inventors
- 👤 Laurence G. Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:04
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/315; B41J2/32; B41J2/335; B41J2/33505; B41J2/3351; B41J2/33515; B41J2/33525; B41J2/3353; B41J2/33535; B41J2/3355; B41J2/33555; B41J2/3357
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
31 words
A thermal printhead comprising: a glass substrate; thin film thermal printing elements disposed on said substrate; thin film conductors disposed on said substrate and electrically connected to said printing elements; and
Claim 2
Dependent Claim
31 words
A thermal printhead comprising: a glass substrate; thin film thermal printing elements disposed on said substrate; thin film conductors disposed on said substrate and electrically connected to said printing elements; and
Claim 3
Dependent Claim
41 words
a protective overcoat consisting of a first layer of silicon monoxide disposed on said substrate, said printing elements and said conductors, and a second layer of a material selected from the group consisting of aluminum oxide, zirconium oxide, and chromium oxide.
Claim 4
Dependent Claim
41 words
a protective overcoat consisting of a first layer of silicon monoxide disposed on said substrate, said printing elements and said conductors, and a second layer of a material selected from the group consisting of aluminum oxide, zirconium oxide, and chromium oxide.
Claim 5
Dependent Claim
24 words
The thermal printhead recited in claim 1 wherein the glass of said substrate is selected from the group consisting of borosilicate and soda-lime glass.
Claim 6
Dependent Claim
15 words
The thermal printhead recited in claim 1 wherein said printing elements are chromium silicon monoxide.
Claim 7
Dependent Claim
38 words
The thermal printhead recited in claim 1 wherein: the glass of said substrate is selected from the group consisting of borosilicate and soda-lime glass; said printing elements are chromium silicon monoxide; and said second layer is aluminum oxide.
Claim 8
Dependent Claim
12 words
The thermal printhead recited in claim 4 wherein said conductors are copper.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |