US3921579A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Means for rapid development of electrostatic images
Assignee: Research Laboratories of Australia Pty Ltd
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Filing: 1974-09-30
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Granted: 1975-11-25
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Expires: 1994-09-30
Abstract
Abstract Electrostatic developing apparatus includes a developerapplicator electrode roller a porous element delivering liquid carrier and developer to the applicator. The element communicates with and through the bottom of a trough member. A vessel, receiving a controlled feed from a reservoir, has an overflow slot through which a drop-wise feed is effected to the trough and its porous element.
Inventors
- 👤 Robert J Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:02
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/10; G03G15/101
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
245 words
Apparatus for electrostatic recording comprising a first set of vertically opposed rollers and a second set of vertically opposed rollers arranged in nip relation for feeding a paper web bearing an electrostatic latent image, means affording a pair of reservoirs positioned above the rollers, one reservoir for supplying to the upper roller in the first set developer liquid comprising electroscopic marking particles suspended in an insulating carrier liquid for developing the latent image, and one reservoir for supplying insulating carrier liquid to the upper roller in the second set, and two distributor means for transferring the liquids from each reservoir to the respective rollers in controlled thin-film form to conserve liquid while displacing background developer from the non-image background areas, each distributor means comprising: a. a receiving trough positioned above the related upper roller and having a porous wiper blade communicating therewith and extending through the bottom thereof and into contact with the related upper roller to meter liquid thereto; b. a distributor vessel operatively associated with the receiving trough for holding a supply of the liquid transferred from the related reservoir, said vessel having an overflow slot therein for substantial drop-wise distribution of liquid into said trough and thereby to the related wiper blade; c. a conduit for transferring liquid by gravity flow from the reservoir to the related distributor vessel; and d. an adjustable valve in said conduit to control the rate of transfer of liquid from the reservoir to said distributor vessel.
Claim 2
Dependent Claim
245 words
Apparatus for electrostatic recording comprising a first set of vertically opposed rollers and a second set of vertically opposed rollers arranged in nip relation for feeding a paper web bearing an electrostatic latent image, means affording a pair of reservoirs positioned above the rollers, one reservoir for supplying to the upper roller in the first set developer liquid comprising electroscopic marking particles suspended in an insulating carrier liquid for developing the latent image, and one reservoir for supplying insulating carrier liquid to the upper roller in the second set, and two distributor means for transferring the liquids from each reservoir to the respective rollers in controlled thin-film form to conserve liquid while displacing background developer from the non-image background areas, each distributor means comprising: a. a receiving trough positioned above the related upper roller and having a porous wiper blade communicating therewith and extending through the bottom thereof and into contact with the related upper roller to meter liquid thereto; b. a distributor vessel operatively associated with the receiving trough for holding a supply of the liquid transferred from the related reservoir, said vessel having an overflow slot therein for substantial drop-wise distribution of liquid into said trough and thereby to the related wiper blade; c. a conduit for transferring liquid by gravity flow from the reservoir to the related distributor vessel; and d. an adjustable valve in said conduit to control the rate of transfer of liquid from the reservoir to said distributor vessel.
Claim 3
Dependent Claim
37 words
Apparatus according to claim 1 in which the upper roller in the first set is a metallic electrode and in which the lower roller in the first set is resilient to assure good contact with the web.
Claim 4
Dependent Claim
195 words
Apparatus for electrostatic recording comprising a set of vertically opposed rollers arranged in nip relation for feeding a paper web bearing an electrostatic latent image, means affording a reservoir for a liquid to be applied to the web, said reservoir being positioned above the rollers, and a distributor means for transferring liquid from the reservoir to the upper one of the rollers in a controlled thin-film form to avoid excessive wetting of the web, said distributor means comprising: a. a receiving trough positioned above the related upper roller and having a porous wiper blade communicating therewith and extending through the bottom thereof and into contact with the upper roller to meter liquid thereto; b. a distributor vessel operatively associated with the receiving trough for holding a supply of liquid transferred from the related reservoir, said vessel having an overflow slot therein for substantial drop-wise distribution of liquid into said trough and to the wiper blade; c. a conduit for transferring liquid by gravity flow from the reservoir to the related distributor vessel; and d. an adjustable valve in said conduit to control the rate of transfer of liquid from the reservoir to said distributor vessel.
Claim 5
Dependent Claim
195 words
Apparatus for electrostatic recording comprising a set of vertically opposed rollers arranged in nip relation for feeding a paper web bearing an electrostatic latent image, means affording a reservoir for a liquid to be applied to the web, said reservoir being positioned above the rollers, and a distributor means for transferring liquid from the reservoir to the upper one of the rollers in a controlled thin-film form to avoid excessive wetting of the web, said distributor means comprising: a. a receiving trough positioned above the related upper roller and having a porous wiper blade communicating therewith and extending through the bottom thereof and into contact with the upper roller to meter liquid thereto; b. a distributor vessel operatively associated with the receiving trough for holding a supply of liquid transferred from the related reservoir, said vessel having an overflow slot therein for substantial drop-wise distribution of liquid into said trough and to the wiper blade; c. a conduit for transferring liquid by gravity flow from the reservoir to the related distributor vessel; and d. an adjustable valve in said conduit to control the rate of transfer of liquid from the reservoir to said distributor vessel.
Claim 6
Dependent Claim
22 words
Apparatus according to claim 3 in which the upper roller is a metallic electrode and in which the opposed roller is resilient.
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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |