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:
Jun. 20, 2017
Filed:
Aug. 11, 2011
Lori-ann S. Prioleau, St. Paul, MN (US);
Justin M. Johnson, Oakdale, MN (US);
Robert D. Lorentz, North Oaks, MN (US);
Brinda B. Badri, Woodbury, MN (US);
James C. Vanous, Roseville, MN (US);
Jacob D. Chatterton, St. Paul, MN (US);
Steven J. Perron, St. Paul, MN (US);
Donald R. Battles, Arden Hills, MN (US);
Badri Veeraraghavan, Woodbury, MN (US);
Lori-Ann S. Prioleau, St. Paul, MN (US);
Justin M. Johnson, Oakdale, MN (US);
Robert D. Lorentz, North Oaks, MN (US);
Brinda B. Badri, Woodbury, MN (US);
James C. Vanous, Roseville, MN (US);
Jacob D. Chatterton, St. Paul, MN (US);
Steven J. Perron, St. Paul, MN (US);
Donald R. Battles, Arden Hills, MN (US);
Badri Veeraraghavan, Woodbury, MN (US);
3M INNOVATIVE PROPERTIES COMPANY, St Paul, MN (US);
Abstract
A wetness sensor includes a self-supporting substrate and an electrically conductive trace carried by the substrate. The trace is patterned to provide at least a portion of a tuned RF circuit, which may be disposed on only one side of the substrate and characterized by an impedance or resistance. The trace is not self-supporting. The substrate is adapted to dissolve, swell, or otherwise degrade when contacted by a target fluid. Such degradation produces a drastic change in the operation of the RF circuit, which can be interpreted by a remote reader as a 'wet' condition. Contact of the substrate by the target fluid may change the impedance or resistance of the RF circuit by at least a factor of 5, 10, 100, or 1000, and/or may cause the trace to disintegrate so as to provide the RF circuit with an open circuit, and/or may substantially render the RF circuit inoperative.