US4316947A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cadmium sulfide for electrophotography
Assignee: Canon Inc
•
Filing: 1980-09-08
•
Granted: 1982-02-23
•
Expires: 2000-09-08
Abstract
Abstract Cadium sulfide for electrophotography is produced by reacting hydrogen sulfide with a solution containing cadmium sulfate, sulfuric acid and hydrochloric acid of a low concentration, and then firing the resulting cadmium sulfide without adding a donor impurity other than that derived from the hydrochloric acid.
Inventors
- 👤 Kiyoshi Suzuki
- 👤 Hirokuni Kawashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:59
CPC Classifications
C; C01; C01G; C01G11/00; C01G11/02; G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
46 words
Cadmium sulfide for electrophotography which is produced by reacting hydrogen sulfide with a solution containing cadmium sulfate, sulfuric acid and hydrochloric acid of a low concentration, and then firing the resulting cadmium sulfide without adding a donor impurity other than that derived from the hydrochloric acid.
Claim 2
Dependent Claim
46 words
Cadmium sulfide for electrophotography which is produced by reacting hydrogen sulfide with a solution containing cadmium sulfate, sulfuric acid and hydrochloric acid of a low concentration, and then firing the resulting cadmium sulfide without adding a donor impurity other than that derived from the hydrochloric acid.
Claim 3
Dependent Claim
25 words
Cadmium sulfide for electrophotography according to claim 1 in which an acceptor impurity is added upon the reaction with hydrogen sulfide or upon the firing.
Claim 4
Dependent Claim
15 words
Cadmium sulfide for electrophotography according to claim 2 in which the acceptor impurity is copper.
References Cited (Backward Citations)
CA632340A
Cited
GB1071062A
Cited
GB1028469A
Cited
GB1215685A
Cited
GB1245712A
Cited
US4197122A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-02-22 | 1985-08-24 | 1986-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-02-22 | 1989-08-24 | 1990-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-02-22 | 1993-08-24 | 1994-02-23 | $7700.00 | Window Closed / Lapsed |