05633835 is referenced by 57 patents and cites 15 patents.

A time indicator that rapidly changes color after a specific time interval is provided. The time indicator includes a base substrate with colored dye deposited on a first surface; a barrier applied over the colored dye; and a substrate having an adhesive on a first surface thereof. The substrate and the base substrate are put into adhesive contact. The adhesive coacts with the barrier to dissolve the barrier in a specified time interval. The adhesive then contacts the colored dye to dissolve the dye and permit the dye to migrate through the adhesive to cause a color change visible through the substrate.

Title
Long term rapid color changing time indicator
Application Number
650221
Publication Number
5633835
Application Date
February 10, 1994
Publication Date
May 27, 1997
Inventor
Sandra F Haas
Suffern
NY, US
David J Haas
Suffern
NY, US
Agent
Michael E Zall
Assignee
Temtec
NY, US
IPC
G04B 17/00
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