US3650797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing electrostatic latent images with a mixture of positive and negative toners
Assignee: Kalle GmbH and Co KG
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Filing: 1970-05-18
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Granted: 1972-03-21
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Expires: 1990-05-18
Abstract
Abstract This invention relates to a developer and process for developing an electrostatic latent image, which process comprises applying to the image, in the absence of a carrier, a mixture consisting of effective amounts of at least one fusible, organic toner capable of acquiring a positive charge, and at least one infusible, inorganic toner of approximately the same effective particle size capable of acquiring a negative charge. The developed image is fused by heating and then treated with an alkaline liquid which removes the inorganic toner particles and renders hydrophilic the image free areas.
Inventors
- 👤 Marthan Tomanek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:22
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/26; G03G13/28; G03G9/00; G03G9/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
34 words
A process according to claim 1 in which the layer having the fused image thereon is treated with an organic alkaline liquid, whereby the image-free areas of the layer are removed from the support.
Claim 2
Dependent Claim
25 words
A process according to claim 1 in which the toners have an average particle size in the range of about 1 to 50 Mu .
Claim 3
Dependent Claim
27 words
A process according to claim 1 in which about 1 to 20 parts by weight of inorganic toner are present Per part by weight of organic toner.
Claim 4
Dependent Claim
21 words
A process according to claim 1 in which the organic toner comprises a colored mixture of polystyrene and a maleinate resin.
Claim 5
Dependent Claim
16 words
A process according to claim 1 in which the organic toner comprises a colored ketone resin.
Claim 6
Dependent Claim
55 words
A process according to claim 1 in which a small quantity, in the range of about 0.1 to 10 per cent by weight, of a compound selected from the group consisting of waxes, aromatic compounds melting in the range of about 40 to 150* C., and substitution products thereof, is added to the organic toner.
Claim 7
Dependent Claim
24 words
A process according to claim 1 in which the toners have an average particle size in the range of 1 to 10 Mu .
Claim 8
Dependent Claim
24 words
A process according to claim 1 in which the toners have an average particle size in the range of 10 to 20 Mu .
Claim 9
Dependent Claim
13 words
A process according to claim 1 in which the inorganic toner is kieselguhr.
Claim 10
Dependent Claim
14 words
A process according to claim 1 in which the inorganic toner is silica gel.
Claim 11
Dependent Claim
13 words
A process according to claim 1 in which the inorganic toner is borax.
Claim 12
Dependent Claim
18 words
A process according to claim 1 in which the inorganic toner is a mixture of kieselguhr and borax.
References Cited (Backward Citations)
US2221776A
Cited
US2297691A
Cited
US2416480A
Cited
US2638416A
Cited
US2940934A
Cited
US2758939A
Cited
US2986521A
Cited
US2952536A
Cited
US3013890A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-21 | 1975-09-20 | 1976-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-21 | 1979-09-20 | 1980-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-21 | 1983-09-20 | 1984-03-21 | $7700.00 | Window Closed / Lapsed |