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.)
Expired
Application number
CA704312A
Inventor
Yamaguchi Goro
Soejima Shigeo
Yanagida Hiroaki
Suwa Yukio
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.)
Niterra Co Ltd
Original Assignee
NGK Spark Plug Co Ltd
Publication date
Application grantedgrantedCritical
Publication of CA704312ApublicationCriticalpatent/CA704312A/en