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. 27, 2015
Filed:
Dec. 30, 2009
Kevin D. Landgrebe, Woodbury, MN (US);
David M. Read, White Bear Lake, MN (US);
Steven S. Kirckof, Woodbury, MN (US);
Kevin D. Landgrebe, Woodbury, MN (US);
David M. Read, White Bear Lake, MN (US);
Steven S. Kirckof, Woodbury, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A chemical indicator composition comprising a bismuth (III) compound selected from the group consisting of bismuth (III) oxide and a bismuth (III) compound comprising at least one organic group which includes 2 to 20 carbon atoms; elemental sulfur; and a compound which makes the composition alkaline when exposed to water vapor at an elevated temperature; a chemical indicator composition comprising a bismuth (III) compound; elemental sulfur; a compound which makes the composition alkaline when exposed to water vapor at an elevated temperature; and at least one acid other than any acid present in the bismuth (III) compound; a chemical indicator comprising a substrate and the composition coated on at least a portion of a major surface of the substrate; methods of making the chemical indicator; and methods of using the chemical indicator are disclosed.