US3220831A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic printing method and apparatus using developer powder projection means
Assignee: Sun Chemical Corp
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Filing: 1962-08-06
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Granted: 1965-11-30
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Expires: 1982-08-06
Abstract
No abstract record available.
Inventors
- 👤 Mcfarlane Samuel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:42
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/75; G03G15/754; G03G15/14; G03G15/16; G03G15/163; Y; Y10; Y10S; Y10S101/00; Y10S101/37
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
170 words
THE METHOD OF ELECTROSTATIC PRINTING COMPRISING THE STEPS OF PRODUCING A LATENT ELECTROSTATIC CHARGE IMAGE ON THE PHOTOCONDUCTIVE LIGHT-SENSITIVE COATED TIPS OF A PLURALITY OF ELECTRICALLY CONDUCTIVE SPACED-APART NEEDLES SET IN AN ELECTRICALLY CONDUCTIVE BACKING MEMBER IN A DISTRIBUTION OF SOME 200 OR MORE PER SQUARE INCH, WHEREIN THE NEEDLES ARE SUBSTANTIALLY PARALLEL AND HAVE THEIR TIPS TERMINATING IN A COMMON SURFACE TO DEFINE A CHARGE IMAGE CARRIER; POWDERING THE IMAGE WITH FINE, GRANULAR MARKING MATERIAL ALONG THE TIPS OF THE COATING; AND, INTRODUCING THE SO-POWDERED IMAGE INTO AN ELECTROSTATIC FIELD ESTABLISHED IN THE AIR TO PROJECT THE MARKING MATERIAL ALONG THE LINES OF ELECTROSTATIC FORCE ONTO A TRANSFER MEDIUM SPACED FROM THE IMAGE IN THE FIELD FOR PRINTING THE IMAGE ON THE TRANSFER MEDIUM, SAID ELECTROSTATIC FIELD BEING CHARACTERIZED BY A VOLTAGE GRADIENT OF APPROXIMATELY 15,000 VOLTS PER INCH AND THE SPACING BETWEEN THE TRANSFER MEDIUM AND THE POWDERED IMAGE ON THE COATED TIPS OF SAID NEEDLES BEING OF THE ORDER OF AT LEAST SEVERAL HUNDREDTHS OF AN INCH.
Claim 2
Independent Claim
170 words
THE METHOD OF ELECTROSTATIC PRINTING COMPRISING THE STEPS OF PRODUCING A LATENT ELECTROSTATIC CHARGE IMAGE ON THE PHOTOCONDUCTIVE LIGHT-SENSITIVE COATED TIPS OF A PLURALITY OF ELECTRICALLY CONDUCTIVE SPACED-APART NEEDLES SET IN AN ELECTRICALLY CONDUCTIVE BACKING MEMBER IN A DISTRIBUTION OF SOME 200 OR MORE PER SQUARE INCH, WHEREIN THE NEEDLES ARE SUBSTANTIALLY PARALLEL AND HAVE THEIR TIPS TERMINATING IN A COMMON SURFACE TO DEFINE A CHARGE IMAGE CARRIER; POWDERING THE IMAGE WITH FINE, GRANULAR MARKING MATERIAL ALONG THE TIPS OF THE COATING; AND, INTRODUCING THE SO-POWDERED IMAGE INTO AN ELECTROSTATIC FIELD ESTABLISHED IN THE AIR TO PROJECT THE MARKING MATERIAL ALONG THE LINES OF ELECTROSTATIC FORCE ONTO A TRANSFER MEDIUM SPACED FROM THE IMAGE IN THE FIELD FOR PRINTING THE IMAGE ON THE TRANSFER MEDIUM, SAID ELECTROSTATIC FIELD BEING CHARACTERIZED BY A VOLTAGE GRADIENT OF APPROXIMATELY 15,000 VOLTS PER INCH AND THE SPACING BETWEEN THE TRANSFER MEDIUM AND THE POWDERED IMAGE ON THE COATED TIPS OF SAID NEEDLES BEING OF THE ORDER OF AT LEAST SEVERAL HUNDREDTHS OF AN INCH.
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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) | 1968-11-29 | 1969-05-31 | 1969-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-29 | 1973-05-31 | 1973-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-29 | 1977-05-31 | 1977-11-30 | $7700.00 | Window Closed / Lapsed |