US3842038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoconductive polymeric condensation products of formaldehyde with a multi-nuclear carbocyclic aromatic compound
Assignee: Kalle GmbH and Co KG
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Filing: 1972-07-24
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Granted: 1974-10-15
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Expires: 1992-07-24
Abstract
Abstract 1. A PHOTOCONDUCTIVE POLYMER CONDENSATION PRODUCT, OF FORMALDEHYDE OR PARA-FORMALDEHYDE AND AT LEAST ONE MULTI-NUCLEAR, CARBOCYCLIC AROMATIC COMPOUND, COMPOSED OF RECURRENT, NON CROSS-LINKED UNITS OF AT LEAST ONE OF THE FOLLOWING FORMULAE -(CH2-(1-X1,X2-PYREN-3, -YLENE))N- AND -(CH2-(3-X3,8-X4- PERYLEN-4, -YLENE))N- WHEREIN X1 AND X2 ARE SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, ALKYL OR ALKOXY WITH 1 TO 4 CARBON ATOMS EACH, OR HALOGEN, X3 AND X4 ARE SELECTED FROM THE GROUP CONSISTING OF ALKYL OR ALKOXY WITH 1 TO 4 CARBON ATOMS EACH, OR HALOGEN, AND N IS AN INTEGER BETWEEN ABOUT 6 AND 10, SAID PRODUCT BEING SOLUBLE IN TETRAHYDROFURAN AT ROOM TEMPERATURE.
Inventors
- 👤 B Loehr
- 👤 H Herrmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:46
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/06; G03G5/07; G03G5/075; G03G5/076; C; C08; C08G; C08G10/00; C08G10/02; C08G16/00; C08G16/02; C08G16/0212; C08G16/0218; C08G16/0225
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
31 words
A PHOTOCONDUCTIVE POLYMER CONDENSATION PRODUCT, OF FORMALDEHYDE OR PARA-FORMALDEHYDE AND AT LEAST ONE MULTI-NUCLEAR, CARBOCYCLIC AROMATIC COMPOUND, COMPOSED OF RECURRENT, NON CROSS-LINKED UNITS OF AT LEAST ONE OF THE FOLLOWING FORMULAE
Claim 2
Dependent Claim
31 words
A PHOTOCONDUCTIVE POLYMER CONDENSATION PRODUCT, OF FORMALDEHYDE OR PARA-FORMALDEHYDE AND AT LEAST ONE MULTI-NUCLEAR, CARBOCYCLIC AROMATIC COMPOUND, COMPOSED OF RECURRENT, NON CROSS-LINKED UNITS OF AT LEAST ONE OF THE FOLLOWING FORMULAE
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |