US4331754A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-spacing touchdown development method
Assignee: Xerox Corp
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Filing: 1977-05-04
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Granted: 1982-05-25
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Expires: 1997-05-04
Abstract
Abstract Dry toner transfer development of latent electrostatic images is achieved by bringing a developer donor into close proximity to the imaged areas, the donor surface bearing raised microelements of "boat" shape for self-spacing the donor surface from the image surface during development.
Inventors
- 👤 Craig H. Stephan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:52
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0806; G03G15/0818; G03G15/0813
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
167 words
An imaging method, comprising: (a) forming an electrostatic latent image on an imaging surface; (b) providing a donor member having adhered to its surface a plurality of raised, discrete micro-elements said micro-elements vertically having essentially straight sides, the ratio of the length to width of said micro-elements being greater than one, at least one end of each element being tapered to resemble a wedge as seen in horizontal cross-section, the elements being so oriented on said donor surface that each element has a tapered end pointing in substantially the same direction as a tapered end of every other element; (c) distributing dry toner on said donor member by moving a doctor edge having a supply of toner associated with it across the tops of said micro-elements in a direction substantially parallel to the lengthwise axis of said micro-elements; and (d) bringing said donor member into self-spacing micro-element contact with said imaging surface to electrostatically transfer toner from the donor to the imaged areas of the image surface.
Claim 2
Dependent Claim
167 words
An imaging method, comprising: (a) forming an electrostatic latent image on an imaging surface; (b) providing a donor member having adhered to its surface a plurality of raised, discrete micro-elements said micro-elements vertically having essentially straight sides, the ratio of the length to width of said micro-elements being greater than one, at least one end of each element being tapered to resemble a wedge as seen in horizontal cross-section, the elements being so oriented on said donor surface that each element has a tapered end pointing in substantially the same direction as a tapered end of every other element; (c) distributing dry toner on said donor member by moving a doctor edge having a supply of toner associated with it across the tops of said micro-elements in a direction substantially parallel to the lengthwise axis of said micro-elements; and (d) bringing said donor member into self-spacing micro-element contact with said imaging surface to electrostatically transfer toner from the donor to the imaged areas of the image surface.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the micro-elements are tapered at both ends of their lengthwise horizontal axis.
Claim 4
Dependent Claim
53 words
The method of claim 1 wherein the micro-element distribution on the donor surface is from about 5 to 100 elements per square millimeter, and where the micro-element height is from about 20 to 100 microns, the length is from about 50 to 150 microns, and the width from about 15 to 40 microns.
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) | 1985-05-24 | 1985-11-23 | 1986-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-24 | 1989-11-23 | 1990-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-24 | 1993-11-23 | 1994-05-25 | $7700.00 | Window Closed / Lapsed |