Patent US3018727A successfully refreshed from Google Patents.
Patent US3850631A successfully refreshed from Google Patents.
US3850631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoconductive element with a polyvinylidene fluoride binder
Assignee: Xerox Ltd
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Filing: 1973-04-24
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Granted: 1974-11-26
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Expires: 1993-04-24
Abstract
Abstract An improved electrophotographic imaging member is provided which comprises a photoconductive powder-polyvinylidene fluoride resin material. A liquid dispersion of a photoconductive powder and polyvinylidene fluoride resin is applied to a suitable substrate material and dried. The substrate thus coated is then heat treated at a temperature higher than the softening point and lower than the decomposition point of polyvinylidene fluoride for a suitable period of time and then slowly cooled. Once cooled, the surface of the imaging member may be polished to improve its charge acceptance. Electrophotographic imaging processes employing this member are also disclosed.
Inventors
- 👤 Y Tamai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:36
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0525
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
101 words
A METHOD OF PROVIDING IMPROVED ELECTROPHOTOGRAPHIC PLATES COMPRISING PROVIDING AN ELECTROCONDUCTIVE BASE, COATING A MIXTURE COMPRISING A POLYVINYLIDENE FLUORIDE AND A PHOTOCONDUCTIVE POWDER THEREOVER TO FORM AN ELECTROPHOTOGRAPHIC MEMBER, SAID POLYVINYLIDENE FLUORIDE HAVING A MOLECULAR WEIGHT RANGE OF BETWEEN 50,000 AND 1,000,000 AND SAID POLYVINYLIDENE FLUORIDE AND PHOTOCONDUCTIVE POWDER TO POLYVINYLIDENE ENT IN A RATIO OF PHOTOCONDUCTIVE POWDER TO POLYVINYLIDINE FLUORIDE OF FROM 2:1 TO 6:1, DRYING SAID MEMBER PRIOR TO HEAT TREATING, HEAT TREATING SAID MEMBER AT A TEMPERATURE OF FROM 190*C TO 320*C FOR FROM 5 MINUTES TO 2 HOURS, ALLOWING SAID MEMBER TO COOL, AND POLISHING SAID MEMBER.
Claim 2
Independent Claim
101 words
A METHOD OF PROVIDING IMPROVED ELECTROPHOTOGRAPHIC PLATES COMPRISING PROVIDING AN ELECTROCONDUCTIVE BASE, COATING A MIXTURE COMPRISING A POLYVINYLIDENE FLUORIDE AND A PHOTOCONDUCTIVE POWDER THEREOVER TO FORM AN ELECTROPHOTOGRAPHIC MEMBER, SAID POLYVINYLIDENE FLUORIDE HAVING A MOLECULAR WEIGHT RANGE OF BETWEEN 50,000 AND 1,000,000 AND SAID POLYVINYLIDENE FLUORIDE AND PHOTOCONDUCTIVE POWDER TO POLYVINYLIDENE ENT IN A RATIO OF PHOTOCONDUCTIVE POWDER TO POLYVINYLIDINE FLUORIDE OF FROM 2:1 TO 6:1, DRYING SAID MEMBER PRIOR TO HEAT TREATING, HEAT TREATING SAID MEMBER AT A TEMPERATURE OF FROM 190*C TO 320*C FOR FROM 5 MINUTES TO 2 HOURS, ALLOWING SAID MEMBER TO COOL, AND POLISHING SAID MEMBER.
Claim 3
Dependent Claim
30 words
The method as defined in claim 1 wherein a solvent is employed with the polyvinylidene fluoride-photoconductive powder mixture, said solvent being selected from the group consisting of dimethylacetoamide and dimethylsulfoxide.
Claim 4
Dependent Claim
46 words
The method as defined in claim 1 wherein said polyvinylidene fluoride resin is employed having an average grain size of less than about 10 microns with said photoconductive powder and a liquid, said liquid being selected from the group consisting of methanol, acetone, and diisobutyl ketone.
Claim 5
Dependent Claim
27 words
The method as defined in claim 1 wherein said conductive base comprises a material selected from the group consisting of aluminum, aluminized steel, stainless steel, and brass.
Claim 6
Dependent Claim
95 words
An improved electrophotographic imaging process comprising providing an improved electrophotographic member, said member comprising photoconductive powder in a polyvinylidene fluoride resin having a molecular weight range of between 50,000 and 1, 000,000 in a ratio of photoconductive powder to polyvinylidene fluoride of from 2:1 to 6:1 coated over an electroconductive base, drying said member prior to heat treating said member at a temperature of from 190to 320C for a period of time from 5 minutes to 2 hours cooling said member, polishing said member, charging said member, selectively exposing said member, and developing said member.
Claim 7
Dependent Claim
95 words
An improved electrophotographic imaging process comprising providing an improved electrophotographic member, said member comprising photoconductive powder in a polyvinylidene fluoride resin having a molecular weight range of between 50,000 and 1, 000,000 in a ratio of photoconductive powder to polyvinylidene fluoride of from 2:1 to 6:1 coated over an electroconductive base, drying said member prior to heat treating said member at a temperature of from 190to 320C for a period of time from 5 minutes to 2 hours cooling said member, polishing said member, charging said member, selectively exposing said member, and developing said member.
Claim 8
Independent Claim
92 words
A method of providing improved electrophotographic plates comprising providing an electroconductive base, coating a mixture comprising polyvinylidene fluoride and a photoconductive powder thereover to form an electrophotographic member, said polyvinylidene fluoride having a molecular weight range of between 50,000 and 1,000,000 drying said member before heat treating, heat treating said member at a temperature of between 190C and 320C for a period of time from 5 minutes to 2 hours said polyvinylidene fluoride being present in a ratio of photoconductor to polyvinylidene fluoride from 2:1 to about 6:1 and polishing said member.
Claim 9
Independent Claim
92 words
A method of providing improved electrophotographic plates comprising providing an electroconductive base, coating a mixture comprising polyvinylidene fluoride and a photoconductive powder thereover to form an electrophotographic member, said polyvinylidene fluoride having a molecular weight range of between 50,000 and 1,000,000 drying said member before heat treating, heat treating said member at a temperature of between 190C and 320C for a period of time from 5 minutes to 2 hours said polyvinylidene fluoride being present in a ratio of photoconductor to polyvinylidene fluoride from 2:1 to about 6:1 and polishing said member.
Claim 10
Dependent Claim
34 words
The method as defined in claim 6 wherein the grain size of said polyvinylidene fluoride is less than 10 microns when employed with a poor solvent and the electrophotographic member is polished after cooling.
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) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |