Patent US4197122A successfully refreshed from Google Patents.
US4197122A
Expired / Lapsed
US
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Process for preparing raw particles of cadmium sulfide for electrophotography
Assignee: Canon Inc
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Filing: 1977-04-29
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Granted: 1980-04-08
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Expires: 1997-04-29
Abstract
Abstract A process for preparing raw particles of cadmium sulfide for electrophotography comprises reacting a solution containing cadmium ion and hydrochloric acid with hydorgen sulfide to make cadmium sulfide particles deposited from the solution.
Inventors
- 👤 Hirokuni Kawashima
- 👤 Kiyoshi Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:24
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
34 words
A process for preparing raw particles of cadmium sulfide for electrophotography which comprises reacting a solution containing cadmium sulfate and added hydrochloric acid with hydrogen sulfide to deposit cadmium sulfide particles from the solution.
Claim 2
Dependent Claim
34 words
A process for preparing raw particles of cadmium sulfide for electrophotography which comprises reacting a solution containing cadmium sulfate and added hydrochloric acid with hydrogen sulfide to deposit cadmium sulfide particles from the solution.
Claim 3
Dependent Claim
40 words
A process for preparing raw particles of cadmium sulfide for electrophotography as claimed in claim 1, wherein said solution further contains at least one impurity element ion selected from the group consisting of a donor impurity and an acceptor impurity.
Claim 4
Dependent Claim
42 words
A process for preparing raw particles of cadmium sulfide for electrophotography as claimed in claim 2 wherein said impurity element ion is an ion of an element selected from the group consisting of In, Al, Ga, Sc, Cl, Cu, Au and Ag.
Claim 5
Dependent Claim
28 words
A process for preparing raw particles of cadmium sulfide for electrophotography as claimed in claim 1 wherein said solution is an aqueous sulfuric acid solution of metallic cadmium.
Claim 6
Dependent Claim
65 words
A process for preparing raw particles of cadmium sulfide for electrophotography as claimed in claim 2 wherein said donor impurity element is an element selected from the group consisting of the elements of Groups IIIa, IIIb and VIIa of the Periodic Table, and wherein said acceptor impurity is an element selected from the group consisting of the elements of Group I of the Periodic Table.
Claim 7
Dependent Claim
75 words
In a process for preparing raw particles of cadmium sulfide for electrophotography which comprises reacting hydrogen sulfide with cadmium sulfate by passing hydrogen sulfide gas through an aqueous solution of cadmium sulfate to deposit cadmium sulfide particles from the solution, the improvement comprising using as said aqueous solution an aqueous solution comprising said cadmium sulfate in the presence of excess sulfuric acid and added hydrochloric acid in a concentration of from 0.01 to 0.5 N.
Claim 8
Dependent Claim
75 words
In a process for preparing raw particles of cadmium sulfide for electrophotography which comprises reacting hydrogen sulfide with cadmium sulfate by passing hydrogen sulfide gas through an aqueous solution of cadmium sulfate to deposit cadmium sulfide particles from the solution, the improvement comprising using as said aqueous solution an aqueous solution comprising said cadmium sulfate in the presence of excess sulfuric acid and added hydrochloric acid in a concentration of from 0.01 to 0.5 N.
Claim 9
Dependent Claim
40 words
A process for preparing raw particles of cadmium sulfide for electrophotography as claimed in claim 6 wherein said aqueous solution further contains at least one impurity ion selected from the group consisting of a donor impurity and an acceptor impurity.
Claim 10
Dependent Claim
42 words
A process for preparing raw particles of cadmium sulfide for electrophotography as claimed in claim 7 wherein said impurity element ion is an ion of an element selected from the group consisting of In, Al, Ga, Sc, Cl, Cu, Au and Ag.
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) | 1983-04-08 | 1983-10-08 | 1984-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-08 | 1987-10-08 | 1988-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-08 | 1991-10-08 | 1992-04-08 | $7700.00 | Window Closed / Lapsed |