FR1451332A
Expired / Lapsed
FR
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Novel di-spiropyran photochromic substances and process for preparing these substances
Assignee: Compagnie de Saint Gobain SA
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Filing: 1965-06-23
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Granted: 1966-01-07
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Expires: 1985-06-23
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
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Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-03 17:18
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/685; C; C07; C07C; C07C205/00; C07C205/13; C07C205/20; C07C205/21; C07C205/22; C07C37/00; C07C37/01; C07C37/045; C07C45/00; C07C45/42; C07C45/43; C07D; C07D209/00; C07D209/02; C07D209/04; C07D209/08
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