The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 12, 1999
Filed:
Nov. 16, 1995
Rodger J Pereyra, Cottage Grove, MN (US);
Russell D Birkholz, Maplewood, MN (US);
Matthew T Scholz, Woodbury, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A critical temperature indicating device is provided. It includes a microporous membrane, an indicating composition containing less than about 10 wt-% water, and means for containing the microporous membrane and the indicating composition. The indicating composition includes: a primary organic component comprising at least one compound that has a freezing point above the critical temperature and does not spontaneously wet out the microporous membrane at a temperature at least about 30.degree. C. above the critical temperature; a modifying component comprising at least one compound that has a freezing point below the critical temperature; and a wetting component comprising at least one compound that has a freezing point below the critical temperature and is capable of spontaneously wetting out the microporous membrane at about the critical temperature.