06244208 is referenced by 41 patents and cites 13 patents.

A time-temperature indicator device provides a visually observable indication of the cumulative thermal exposure of an object. The device includes a substrate having a diffusely light-reflective porous matrix and a backing. The backing includes on its surface a viscoelastic indicator material for contacting the substrate and a barrier material for substantially inhibiting the lateral flow of viscoelastic indicator material between the substrate and the backing.

Title
Time-temperature integrating indicator device with barrier material
Application Number
9/69576
Publication Number
6244208 (B1)
Application Date
April 29, 1998
Publication Date
June 12, 2001
Inventor
David J Yarusso
Shoreview
MN, US
Joan M Noyola
Maplewood
MN, US
Jean Qiu
Woodbury
MN, US
Assignee
3M Innovative Properties Company
MN, US
IPC
G01K 3/00
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