06214623 is referenced by 38 patents and cites 7 patents.

A time-temperature indicator device comprises a polymeric layer having a first and second surface and a dye composition adhered to said first surface comprising a dye which diffuses into the polymeric layer as a result of a cumulative time-temperature exposure wherein the dye is invisible when viewed in visible radiation and is detectable as a result of absorption of non-visible radiation. The device may be attached to a product for monitoring cumulative time-temperature exposure.

Title
Time-temperature indicator devices
Application Number
9/176498
Publication Number
6214623 (B1)
Application Date
October 21, 1998
Publication Date
April 10, 2001
Inventor
John A Weldy
Rochester
NY, US
Michael J Simons
Eastcote
US
Agent
Clyde E Bailey Sr
US
Assignee
Eastman Kodak Company
NY, US
IPC
G01K 3/04
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