DE686737C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Method for determining the density of photographic negatives
Assignee: AXEL KOELLING DR
•
Filing: 1938-03-13
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Granted: 1940-01-15
•
Expires: 1958-03-13
Abstract
No abstract record available.
Inventors
- 👤 Dr Axel Koelling
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-11-06 16:34
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/255
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