US3623841A
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Separation by thin-layer chromatography with a two-layer plate
Assignee: Merck Patent GmbH
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Filing: 1969-07-15
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Granted: 1971-11-30
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Expires: 1989-07-15
Abstract
Abstract THIN-LAYER CHROMATOGRAPHIC PLATES ARE PROVIDED WITH TWO LAYERS, ONE FOR THE REMOVAL OF INTERFERING CONSTITUENTS AND THE OTHER FOR THE SEPARATION OF AMINO ACIDS.
Inventors
- 👤 Friedrich Kraffczyk
- 👤 Roland Helger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:39
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/90; G01N30/92; G01N30/93; B; B01; B01J; B01J20/00; B01J20/281; B01J20/286; B01J20/30; B01J20/32; B01J20/3202; B01J20/3204; B01J20/3206; B01J20/3208; B01J20/321; B01J20/3212; B01J20/3231; B01J20/3242; B01J20/3268; B01J20/327; B01J20/3272; B01J39/00; B01J39/04; B01J39/05; B01J39/08; B01J39/16; B01J39/18; B01J39/20; B01J39/22; B01J39/26; B01J41/00; B01J41/04; B01J41/05; B01J41/08; B01J41/12; B01J41/14; B01J41/16; B01J47/00; B01J47/016; B01J2220/00; B01J2220/50; B01J2220/54
Claims Analysis
Total Claims: 0
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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) | 1974-11-29 | 1975-05-31 | 1975-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-29 | 1979-05-31 | 1979-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-29 | 1983-05-31 | 1983-11-30 | $7700.00 | Window Closed / Lapsed |