Legal status (The legal status 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 status listed.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Tungsten Co Ltd
Original Assignee
Nippon Tungsten Co Ltd
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
Application filed by Nippon Tungsten Co LtdfiledCriticalNippon Tungsten Co Ltd
Priority to JP49096732ApriorityCriticalpatent/JPS5123688A/ja
Publication of JPS5123688ApublicationCriticalpatent/JPS5123688A/ja