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US3881925A
Expired / Lapsed
US
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Bi-chargeable electrophotographic materials including zinc oxide and a binder resin
Assignee: Mitsubishi Paper Mills Ltd
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Filing: 1973-07-17
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Granted: 1975-05-06
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Expires: 1993-07-17
Abstract
Abstract An electrophotographic material chargeable both positively and negatively comprising a zinc oxide type electrophotographic layer containing as the binder for zinc oxide a copolymerized acrylic resin comprising 50-95% by weight acrylic ester and 1-5% by weight organic acid having vinyl group copolymerizable with the acrylic ester. The electrophotographic layer may contain further low-molecular weight polystyrene.
Inventors
- 👤 Koji Uchida
- 👤 Shigeyoshi Suzuki
- 👤 Sadao Kuriu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:32
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0528; G03G5/0532; G03G5/0546
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
115 words
A BI-CHARGEABLE ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MATERIAL CONTAINING PHOTOCONDUCTIVE ZINC OXIDE AND A BINDER RESIN COMPRISING A MIXTURE OF: 1. 50 TO 90% BY WEIGHT, BASED ON THE WEIGHT OF SAID BINDER RESIN, OF AN ACRYLIC COPOLYMER COMPRISING A. 50 TO 90% BY WEIGHT OF AT LEAST ONE LOWER ALKYL ACRYLATE, B. 1 TO 5Z BY WEIGHT OF AT LEAST ONE ORGANIC ACID HAVING A VINYL GROUP COPOLYMERIAZABLE WITH SAID AT LEAST ONE LOWER ALKYL ACRYLATE, AND C. O TO 49% BY WEIGHT OF AT LEAST ONE OTHER COMPOLYMERIZABLE VINYL MONOMER, AND 2. 10 TO 50% BY WEIGHT, BASED ON THE WEIGHT OF SAID BINDER RESIN, OF A POLYSTYRENE HAVING A MOLEUCLAR WEIGHT OF LESS THAN 5,000.
Claim 2
Dependent Claim
115 words
A BI-CHARGEABLE ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MATERIAL CONTAINING PHOTOCONDUCTIVE ZINC OXIDE AND A BINDER RESIN COMPRISING A MIXTURE OF: 1. 50 TO 90% BY WEIGHT, BASED ON THE WEIGHT OF SAID BINDER RESIN, OF AN ACRYLIC COPOLYMER COMPRISING A. 50 TO 90% BY WEIGHT OF AT LEAST ONE LOWER ALKYL ACRYLATE, B. 1 TO 5Z BY WEIGHT OF AT LEAST ONE ORGANIC ACID HAVING A VINYL GROUP COPOLYMERIAZABLE WITH SAID AT LEAST ONE LOWER ALKYL ACRYLATE, AND C. O TO 49% BY WEIGHT OF AT LEAST ONE OTHER COMPOLYMERIZABLE VINYL MONOMER, AND 2. 10 TO 50% BY WEIGHT, BASED ON THE WEIGHT OF SAID BINDER RESIN, OF A POLYSTYRENE HAVING A MOLEUCLAR WEIGHT OF LESS THAN 5,000.
Claim 3
Dependent Claim
24 words
10 to 50% by weight, based on the weight of said binder resin, of a polystyrene having a molecular weight of less than 5,000.
Claim 4
Dependent Claim
24 words
10 to 50% by weight, based on the weight of said binder resin, of a polystyrene having a molecular weight of less than 5,000.
Claim 5
Dependent Claim
23 words
The bi-chargeable electrophotographic photosensitive material as claimed in claim 1 wherein said lower alkyl acrylate is methyl acrylate, ethyl acrylate, or butyl acrylate.
Claim 6
Dependent Claim
37 words
The bi-chargeable electrophotographic photosensitive material as claimed in claim 1 wherein said organic acid is acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, maleic anhydride, itaconic anhydride, or the monoester of each of said acids.
Claim 7
Dependent Claim
36 words
The bi-chargeable electrophotographic photosensitive material as claimed in claim 1 wherein said other copolymerizable vinyl monomer is methyl methacrylate, ethyl methacrylate, butyl methacrylate, a derivative of acrylic ester or methacrylic acid, styrene or a styrene derivative.
Claim 8
Dependent Claim
17 words
The bi-chargeable electrophotographic photosensitive material as claimed in claim 1 which consists essentially of the recited components.
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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |