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 US06/221,753external-prioritypatent/US4364855A/en
Priority claimed from US06/221,747external-prioritypatent/US4364854A/en
Application filed by Phillips Petroleum CofiledCriticalPhillips Petroleum Co
Priority claimed from EP81110847Aexternal-prioritypatent/EP0056164B1/de
Application grantedgrantedCritical
Publication of ATE14561T1publicationCriticalpatent/ATE14561T1/de