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
CA829831A
Inventor
F. Borth Paul
Mckeone Joseph
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.)
PHOTO-ENGRAVERS RESEARCH INSTITUTE
Original Assignee
PHOTO-ENGRAVERS RESEARCH INSTITUTE
Publication date
Application grantedgrantedCritical
Publication of CA829831ApublicationCriticalpatent/CA829831A/en