Patent US3305520A successfully refreshed from Google Patents.
US3305520A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polycarbonates stabilized by phosphites
Assignee: Bayer AG
•
Filing: 1965-04-06
•
Granted: 1967-02-21
•
Expires: 1985-04-06
Abstract
No abstract record available.
Inventors
- 👤 Fritz Gerhard
- 👤 Bottenbruch Ludwig
- 👤 Schnell Hermann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:53
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/49; C08K5/51; C08K5/52; C08K5/524
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
32 words
A POLYCARBONATE PLASTIC DERIVED FROM A DIPHENOL AND STABILIZED AGAINST DISCOLORATION BY A MEMBER SELECTED FROM THE GROUP CONSISTING OF A TRIALKYL PHOSPHITE, A TRIARYL PHOSPHITE AND A MIXED TRI (ALKYL-ARYL) PHOSPHITE.
Claim 2
Dependent Claim
32 words
A POLYCARBONATE PLASTIC DERIVED FROM A DIPHENOL AND STABILIZED AGAINST DISCOLORATION BY A MEMBER SELECTED FROM THE GROUP CONSISTING OF A TRIALKYL PHOSPHITE, A TRIARYL PHOSPHITE AND A MIXED TRI (ALKYL-ARYL) PHOSPHITE.
References Cited (Backward Citations)
US3053810A
Cited
US3043808A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-02-20 | 1970-08-22 | 1971-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-02-20 | 1974-08-22 | 1975-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-02-20 | 1978-08-22 | 1979-02-21 | $7700.00 | Window Closed / Lapsed |