US3784301A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrophotographic border apparatus
Assignee: Xerox Corp
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Filing: 1972-01-07
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Granted: 1974-01-08
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Expires: 1992-01-07
Abstract
Abstract Apparatus for producing a toner-free border surrounding an image region on a charged photoconductive insulating layer comprising imagewise exposure means, electromagnetic radiation means for uniformly exposing the border portions of the photoconductive insulating layer and an electromagnetic radiation intercepting shielding plate positioned perpendicularly adjacent to the photoconductive insulating layer and a covering plate parallel and adjacent to the photoconductive insulating layer arranged to provide uniform exposure only on the desired width of the tonerfree border sought while maintaining a charged surface surrounding and external to the desired toner-free border. Use of the apparatus in electrophotographic imaging results in a photoconductive insulating layer having an image region thereon, a uniformly exposed region surrounding the image region and a charged region surrounding the uniformly exposed region. Toner is thus attracted away from the intermediate, uniformly exposed region, and towards the image and charged regions on either side thereof. Upon transfer of the developing toner to a substrate, the substrate bears a toner-free border around the image region and corresponds to the uniformly exposed intermediate region of the photoconductive insulating layer.
Inventors
- 👤 M Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:01
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/04; G03G15/045; G03G15/047; G03G2215/00; G03G2215/04; G03G2215/0429; G03G2215/0468; G03G2215/048; G03G2215/0482
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
277 words
Apparatus for producing a toner-free border surrounding an imagewise exposed region on a charged photoconductive insulating layer comprising: a. imagewise exposure means including first electromagnetic radiation means for imagewise exposing a photoconductive insulating layer; b. second electromagnetic radiation means for uniformly exposing a border surrounding the imagewise exposed region of the photoconductive insulating layer at a radiation intensity at least equal to the maximum radiation intensity within the imagewise exposed region so that the border, upon uniform exposure, is discharged to a residual charge level no greater than the lowest charge level within the imagewise exposed region; c. an electromagnetic radiation intercepting shielding plate, impenetrable by electromagnetic radiation from said second electromagnetic radiation means positioned perpendicularly adjacent to, but out of contact with, the surface of the photoconductive insulating layer such that the imagewise exposed region is shielded thereby from electromagnetic radiation from said second electromagnetic radiation means; and d. a covering plate, impenetrable by electromagnetic radiation from said second electromagnetic radiation means positioned parallel and adjacent to, but out of contact with, the photoconductive insulating layer surface surrounding the imagewise exposed region and at a distance from said electromagnetic radiation intercepting shielding plate equaling the desired width of the border sought to be free of toner so as to allow uniform exposure of the cHarged photoconductive insulating layer surface surrounding the imagewise exposed region to radiation from said second electromagnetic radiation means along the desired width of the toner-free border sought while maintaining a charged photoconductive insulating layer surface, which charged surface surrounds and is external to the tonerfree border and is of a charge lever greater than the residual charge level of the toner-free border.
Claim 2
Dependent Claim
277 words
Apparatus for producing a toner-free border surrounding an imagewise exposed region on a charged photoconductive insulating layer comprising: a. imagewise exposure means including first electromagnetic radiation means for imagewise exposing a photoconductive insulating layer; b. second electromagnetic radiation means for uniformly exposing a border surrounding the imagewise exposed region of the photoconductive insulating layer at a radiation intensity at least equal to the maximum radiation intensity within the imagewise exposed region so that the border, upon uniform exposure, is discharged to a residual charge level no greater than the lowest charge level within the imagewise exposed region; c. an electromagnetic radiation intercepting shielding plate, impenetrable by electromagnetic radiation from said second electromagnetic radiation means positioned perpendicularly adjacent to, but out of contact with, the surface of the photoconductive insulating layer such that the imagewise exposed region is shielded thereby from electromagnetic radiation from said second electromagnetic radiation means; and d. a covering plate, impenetrable by electromagnetic radiation from said second electromagnetic radiation means positioned parallel and adjacent to, but out of contact with, the photoconductive insulating layer surface surrounding the imagewise exposed region and at a distance from said electromagnetic radiation intercepting shielding plate equaling the desired width of the border sought to be free of toner so as to allow uniform exposure of the cHarged photoconductive insulating layer surface surrounding the imagewise exposed region to radiation from said second electromagnetic radiation means along the desired width of the toner-free border sought while maintaining a charged photoconductive insulating layer surface, which charged surface surrounds and is external to the tonerfree border and is of a charge lever greater than the residual charge level of the toner-free border.
Claim 3
Dependent Claim
35 words
The apparatus of claim 1, wherein the perpendicular end portions of said electromagnetic radiation intercepting shielding plate and the parallel portions of said covering plate nearest the surface of the photo-conductive insulating layer are sharp.
Claim 4
Dependent Claim
269 words
Apparatus for producing a toner-free border surrounding an imagewise exposed region on a charged photoconductive insulating layer comprising: a. imagewise exposure means including first electromagnetic radiation means for imagewise exposing a photoconductive insulating layer for uniformly exposing a border surrounding the imagewise exposed region of the photoconductive insulating layer at a radiation intensity at least equal to the maximum radiation intensity within the imagewise exposed region so that the border, upon uniform exposure, is discharged to a residual charge level no greater than the lowest charge level eithin the imagewise exposed region; b. an electromagnetic radiation intercepting shielding plate, impenetrable by electromagnetic radiation from said electromagnetic radiation means positioned perpendicularly adjacent to, but out of contact with, the surface of the photoconductive insulating layer such that the imagewise exposed region is shielded thereby from electromagnetic radiation from said second electromagnetic radiation means; and c. a covering plate, impenetrable by electromagnetic radiation from said electromagnetic radiation means positioned parallel and adjacent to, but out of contact with, the photoconductive insulating layer surface surrounding the imagewise exposed region and at a distance from said electromagnetic radiation intercepting shielding plate equaling the desired width of the border sought to be free of toner so as to allow uniform exposure of the charged photoconductive insulating layer surface surrounding the imagewise exposed region to radiation from said electromagnetic radiation means along the desired width of the toner-free border sought while maintaining a charged photoconductive insulating layer surface, which charged surface surrounds and is external to the toner-free border and is of a charge level greater than the residual charge level of the toner-free border.
Claim 5
Dependent Claim
269 words
Apparatus for producing a toner-free border surrounding an imagewise exposed region on a charged photoconductive insulating layer comprising: a. imagewise exposure means including first electromagnetic radiation means for imagewise exposing a photoconductive insulating layer for uniformly exposing a border surrounding the imagewise exposed region of the photoconductive insulating layer at a radiation intensity at least equal to the maximum radiation intensity within the imagewise exposed region so that the border, upon uniform exposure, is discharged to a residual charge level no greater than the lowest charge level eithin the imagewise exposed region; b. an electromagnetic radiation intercepting shielding plate, impenetrable by electromagnetic radiation from said electromagnetic radiation means positioned perpendicularly adjacent to, but out of contact with, the surface of the photoconductive insulating layer such that the imagewise exposed region is shielded thereby from electromagnetic radiation from said second electromagnetic radiation means; and c. a covering plate, impenetrable by electromagnetic radiation from said electromagnetic radiation means positioned parallel and adjacent to, but out of contact with, the photoconductive insulating layer surface surrounding the imagewise exposed region and at a distance from said electromagnetic radiation intercepting shielding plate equaling the desired width of the border sought to be free of toner so as to allow uniform exposure of the charged photoconductive insulating layer surface surrounding the imagewise exposed region to radiation from said electromagnetic radiation means along the desired width of the toner-free border sought while maintaining a charged photoconductive insulating layer surface, which charged surface surrounds and is external to the toner-free border and is of a charge level greater than the residual charge level of the toner-free border.
Claim 6
Dependent Claim
207 words
Apparatus for producing a toner-free border surrounding an imagewise exposed region on a charged photoconductive insulating layer comprising: a. imagewise exposure means including first electromagnetic radiation means for imagewise exposing a photoconductive insulating layer; b. second electromagnetic radiation means which may be the same as the electromagnetic radiation means recited in part (a) above or a separate electromagnetic radiation means for uniformly exposing a border surrounding the imagewise exposed region of the photoconductive insulating layer at a radiation intensity at least equal to the maximum radiation intensity within the imagewise exposed region so that the border, upon uniform exposure, is discharged to a residual charge level no greater than the lowest charge level within the imagewise exposed region; c. an electromagnetic radiation intercepting shielding plate, impenetrable by electromagnetic radiation from said second electromagnetic radiation means positioned perpendicularly adjacent to, but out of contact with, the surface of the photoconductive insulating layer such that the imagewise exposed region is shielded thereby from electromagnetic radiation from said second electromagnetic radiation means; and d. an insulating surface insensitive to electromagnetic radiation from said second electromagnetic radiation means lyinG substantially in the same plane as the surface of the photoconductive insulating layer, surrounding the photoconductive insulating layer and in contact therewith.
Claim 7
Dependent Claim
207 words
Apparatus for producing a toner-free border surrounding an imagewise exposed region on a charged photoconductive insulating layer comprising: a. imagewise exposure means including first electromagnetic radiation means for imagewise exposing a photoconductive insulating layer; b. second electromagnetic radiation means which may be the same as the electromagnetic radiation means recited in part (a) above or a separate electromagnetic radiation means for uniformly exposing a border surrounding the imagewise exposed region of the photoconductive insulating layer at a radiation intensity at least equal to the maximum radiation intensity within the imagewise exposed region so that the border, upon uniform exposure, is discharged to a residual charge level no greater than the lowest charge level within the imagewise exposed region; c. an electromagnetic radiation intercepting shielding plate, impenetrable by electromagnetic radiation from said second electromagnetic radiation means positioned perpendicularly adjacent to, but out of contact with, the surface of the photoconductive insulating layer such that the imagewise exposed region is shielded thereby from electromagnetic radiation from said second electromagnetic radiation means; and d. an insulating surface insensitive to electromagnetic radiation from said second electromagnetic radiation means lyinG substantially in the same plane as the surface of the photoconductive insulating layer, surrounding the photoconductive insulating layer and in contact therewith.
Claim 8
Dependent Claim
26 words
The apparatus of claim 4, wherein the end portions of said electromagnetic radiation intercepting shielding plate near the surface of the photoconductive insulating layer are sharp.
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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) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |