Patent US3252844A successfully refreshed from Google Patents.
US3252844A
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Method of obtaining a matte surface on polycarbonate
Assignee: Bayer AG
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Filing: 1962-02-14
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Granted: 1966-05-24
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Expires: 1982-02-14
Abstract
No abstract record available.
Inventors
- 👤 Hechelhammer Wilhelm
- 👤 Streib Hugo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:22
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/12; D; D01; D01F; D01F6/00; D01F6/58; D01F6/62; D01F6/64; D06; D06M; D06M11/00; D06M11/32; D06M11/36; D06M11/38; D06M11/44; D06M13/00; D06M13/10; D06M13/144; C08J2369/00; Y; Y10; Y10T; Y10T428/00; Y10T428/31
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
59 words
A METHOD FOR IMPARTING A MATTE FINISH TO THE SURFACE OF A SHAPED POLYCARBONATE ARTICLE SUBSTANTIALLY INSTANTANEOUSLY WHICH COMPRISES TREATING THE SURFACE WITH A SOLUTION OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDE AND ALKALINE EARTH METAL HYDROXIDE AT A CONCENTRATION OF ABOUT 50% AND AT A TEMPERATURE OF BETWEEN ABOUT 80*C. AND ABOUT 120*C.
Claim 2
Independent Claim
59 words
A METHOD FOR IMPARTING A MATTE FINISH TO THE SURFACE OF A SHAPED POLYCARBONATE ARTICLE SUBSTANTIALLY INSTANTANEOUSLY WHICH COMPRISES TREATING THE SURFACE WITH A SOLUTION OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL HYDROXIDE AND ALKALINE EARTH METAL HYDROXIDE AT A CONCENTRATION OF ABOUT 50% AND AT A TEMPERATURE OF BETWEEN ABOUT 80*C. AND ABOUT 120*C.
References Cited (Backward Citations)
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-05-23 | 1969-11-22 | 1970-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-23 | 1973-11-22 | 1974-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-23 | 1977-11-22 | 1978-05-24 | $7700.00 | Window Closed / Lapsed |