US3687072A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic copying
Assignee: Masson Scott Thrissell Engineering Ltd
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Filing: 1970-03-12
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Granted: 1972-08-29
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Expires: 1990-03-12
Abstract
Abstract A method and apparatus for printing or copying, using a gravure cylinder and a controlled electrostatic field for governing the movement of ink from the gravure cells. The control of the field is performed by applying controlled illumination onto a photoconductive material below or within the cells, or the ink or ink particles may itself by photo-conductive.
Inventors
- 👤 Michael Aren Pym
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:57
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; B; B41; B41M; B41M1/00; B41M1/42; G03F; G03F5/00; G03F5/20; G03G15/24; G03G17/00; G03G17/04
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
180 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located in each of said recesses, to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic field at said surface of said imaging member, the local strength of said field being varied by reason of and in accordance with the said conductive pattern of said photo-conductive material, whereby said liquid printing medium is lifted partly out of corresponding ones of said recesses, removing the upstanding liquid medium with a doctor blade, discontinuing the controlled electrostatic field to allow the liquid medium to collapse into said recesses, and thereafter establishing a substantially uniform electrostatic field to transfer the remaining liquid medium from said recesses in the form of a negative image onto an article to receive said pattern.
Claim 2
Independent Claim
180 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located in each of said recesses, to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic field at said surface of said imaging member, the local strength of said field being varied by reason of and in accordance with the said conductive pattern of said photo-conductive material, whereby said liquid printing medium is lifted partly out of corresponding ones of said recesses, removing the upstanding liquid medium with a doctor blade, discontinuing the controlled electrostatic field to allow the liquid medium to collapse into said recesses, and thereafter establishing a substantially uniform electrostatic field to transfer the remaining liquid medium from said recesses in the form of a negative image onto an article to receive said pattern.
Claim 3
Dependent Claim
130 words
Apparatus for copying, comprising a rotary imaging member having a plurality of closely spaced small recesses of uniform size distributed uniformly over a surface thereof, and a layer of photo-conductive material lying in each recess, means for introducing a liquid printing medium into each of said recesses, means for projecting an optical image onto said photo-conductive material to render parts thereof conductive, means for establishing an electrostatic field at said surface of said imaging member, whereby the strength of said field varies over the surface of said imaging member in accordance with the pattern of conductive areas in said photo-conductive material, and means for conveying an article to receive said pattern past said surface of the member, whereby said printing medium is transferred in a corresponding pattern onto said article.
Claim 4
Dependent Claim
130 words
Apparatus for copying, comprising a rotary imaging member having a plurality of closely spaced small recesses of uniform size distributed uniformly over a surface thereof, and a layer of photo-conductive material lying in each recess, means for introducing a liquid printing medium into each of said recesses, means for projecting an optical image onto said photo-conductive material to render parts thereof conductive, means for establishing an electrostatic field at said surface of said imaging member, whereby the strength of said field varies over the surface of said imaging member in accordance with the pattern of conductive areas in said photo-conductive material, and means for conveying an article to receive said pattern past said surface of the member, whereby said printing medium is transferred in a corresponding pattern onto said article.
Claim 5
Dependent Claim
36 words
Apparatus according to claim 2, in which said photo-conductive material is in the form of a continuous layer behind said recesses, and said optical projection means is situated on the rear side of said photo-conductive layer.
Claim 6
Dependent Claim
37 words
Apparatus according to claim 2, in which said imaging member comprises an inner transparent insulating member, a surrounding transparent conducting layer, a photo-conductive layer surrounding said conductive layer, and an insulating surface layer formed with said recesses.
Claim 7
Independent Claim
142 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located in said recesses to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic transfer field between said surface and an article to receive said patteRn, the said electrostatic field being of variable strength over different sections of said surface by reason of said conductive pattern of photo-conductive material, whereby said printing medium is transferred onto said receiving article from those of said recesses of the imaging surface which lie adjacent to said conductive portions of said photo-conductive material.
Claim 8
Independent Claim
142 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located in said recesses to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic transfer field between said surface and an article to receive said patteRn, the said electrostatic field being of variable strength over different sections of said surface by reason of said conductive pattern of photo-conductive material, whereby said printing medium is transferred onto said receiving article from those of said recesses of the imaging surface which lie adjacent to said conductive portions of said photo-conductive material.
Claim 9
Independent Claim
142 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located adjacent said recesses to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic transfer field between said surface and an article to receive said pattern, the said electrostatic field being of variable strength over different sections of said surface by reason of said conductive pattern of photo-conductive material, whereby said printing medium is transferred onto said receiving article from those of said recesses of the imaging surface which lie adjacent to said conductive portions of said photo-conductive material.
Claim 10
Independent Claim
142 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located adjacent said recesses to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic transfer field between said surface and an article to receive said pattern, the said electrostatic field being of variable strength over different sections of said surface by reason of said conductive pattern of photo-conductive material, whereby said printing medium is transferred onto said receiving article from those of said recesses of the imaging surface which lie adjacent to said conductive portions of said photo-conductive material.
Claim 11
Independent Claim
180 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located adjacent each of said recesses, to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic field at said surface of said imaging member, the local strength of said field being varied by reason of and in accordance with the said conductive pattern of said photo-conductive material, whereby said liquid printing medium is lifted partly out of corresponding ones of saId recesses, removing the upstanding liquid medium with a doctor blade, discontinuing the controlled electrostatic field to allow the liquid medium to collapse into said recesses, and thereafter establishing a substantially uniform electrostatic field to transfer the remaining liquid medium from said recesses in the form of a negative image onto an article to receive said pattern.
Claim 12
Independent Claim
180 words
A method of copying using an imaging member having a surface formed with a plurality of closely spaced small recesses of uniform size distributed substantially uniformly over said surface, comprising introducing a liquid printing medium into said recesses in said imaging member surface, projecting an optical image onto photo-conductive material located adjacent each of said recesses, to cause portions of said photo-conductive material to become locally and temporarily conductive in the pattern of said optical image, establishing an electrostatic field at said surface of said imaging member, the local strength of said field being varied by reason of and in accordance with the said conductive pattern of said photo-conductive material, whereby said liquid printing medium is lifted partly out of corresponding ones of saId recesses, removing the upstanding liquid medium with a doctor blade, discontinuing the controlled electrostatic field to allow the liquid medium to collapse into said recesses, and thereafter establishing a substantially uniform electrostatic field to transfer the remaining liquid medium from said recesses in the form of a negative image onto an article to receive said pattern.
Claim 13
Dependent Claim
130 words
Apparatus for copying, comprising a rotary imaging member having a plurality of closely spaced small recesses of uniform size distributed uniformly over a surface thereof, and a layer of photo-conductive material lying behind each recess, means for introducing a liquid printing medium into each of said recesses, means for projecting an optical image onto said photo-conductive material to render parts thereof conductive, means for establishing an electrostatic field at said surface of said imaging member, whereby the strength of said field varies over the surface of said imaging member in accordance with the pattern of conductive areas in said photo-conductive material, and means for conveying an article to receive said pattern past said surface of the member, whereby said printing medium is transferred in a corresponding pattern onto said article.
Claim 14
Dependent Claim
130 words
Apparatus for copying, comprising a rotary imaging member having a plurality of closely spaced small recesses of uniform size distributed uniformly over a surface thereof, and a layer of photo-conductive material lying behind each recess, means for introducing a liquid printing medium into each of said recesses, means for projecting an optical image onto said photo-conductive material to render parts thereof conductive, means for establishing an electrostatic field at said surface of said imaging member, whereby the strength of said field varies over the surface of said imaging member in accordance with the pattern of conductive areas in said photo-conductive material, and means for conveying an article to receive said pattern past said surface of the member, whereby said printing medium is transferred in a corresponding pattern onto said article.
Claim 15
Dependent Claim
36 words
Apparatus according to claim 8, in which said photo-conductive material is in the form of a continuous layer behind said recesses, and said optical projection means is situated on the rear side of said photo-conductive layer.
Claim 16
Dependent Claim
37 words
Apparatus according to claim 8, in which said imaging member comprises an inner transparent insulating member, a surrounding transparent conducting layer, a photo-conductive layer surrounding said conductive layer, and an insulating surface layer formed with said recesses.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |