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Priority claimed from US06/656,293external-prioritypatent/US4600426A/en
Priority claimed from US06/656,292external-prioritypatent/US4610711A/en
Application filed by Ppg Industries IncfiledCriticalPpg Industries Inc
Priority claimed from EP19850111983external-prioritypatent/EP0176898B1/en
Application grantedgrantedCritical
Publication of ATE38974T1publicationCriticalpatent/ATE38974T1/en