Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from US07/082,698external-prioritypatent/US4758542A/en
Application filed by Grace W R & CofiledCriticalGrace W R & Co
Application grantedgrantedCritical
Publication of ATE84290T1publicationCriticalpatent/ATE84290T1/en