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
CA811728A
Inventor
Chang Wen-Hsuan
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.)
PPG Industries Inc
Original Assignee
PPG Industries Inc
Publication date
Application grantedgrantedCritical
Publication of CA811728ApublicationCriticalpatent/CA811728A/en