Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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IG Farbenindustrie AG
Original Assignee
IG Farbenindustrie AG
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Filing date
Publication date
Application filed by IG Farbenindustrie AGfiledCriticalIG Farbenindustrie AG
Application grantedgrantedCritical
Publication of FR777760ApublicationCriticalpatent/FR777760A/en
G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
G11B23/38—Visual features other than those contained in record tracks or represented by sprocket holes the visual signals being auxiliary signals
G11B23/42—Marks for indexing, speed-controlling, synchronising, or timing
FR777760D1933-10-191934-08-27
Method and device for reproducing or taking photographic sound recordings arranged in a spiral
ExpiredFR777760A
(en)