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.)
3M Co
Original Assignee
The Minnesota Mining & Manufacturing Company
Walton W. Welna
Minnesota Mining And Manufacturing Company
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 US08/567,956external-prioritypatent/US5578671A/en
Application filed by The Minnesota Mining & Manufacturing Company, Walton W. Welna, Minnesota Mining And Manufacturing CompanyfiledCriticalThe Minnesota Mining & Manufacturing Company
Publication of CA2208602A1publicationCriticalpatent/CA2208602A1/en
Application grantedgrantedCritical
Publication of CA2208602CpublicationCriticalpatent/CA2208602C/en
This invention relates to non-aqueous, indefinitely conformable, halogen free, intumescent putty useful in an opening as a firestop material to deter the spread of fire, smoke, and vapors during a fire.