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Priority claimed from US06/665,680external-prioritypatent/US4610771A/en
Application filed by Ppg Industries IncfiledCriticalPpg Industries Inc
Priority claimed from EP89113298Aexternal-prioritypatent/EP0343695B1/en
Application grantedgrantedCritical
Publication of ATE85312T1publicationCriticalpatent/ATE85312T1/en