04737463 is referenced by 46 patents and cites 11 patents.

A photoactivated time-temperature indicator is based on diacetylenic salts. A thermally unreactive ("inactive") diacetylenic salt (or a mixture of such salts) is mixed, in a polymeric matrix, with a material that generates acid upon exposure to light. Photoexcitation, preferably by UV or near UV light, causes the formation of a thermal reactive ("active") free diacetylenic acid. Following this activation step, a progressive color development occurs at a rate that increases with temperature. The indicator is useful for monitoring the freshness of perishable products, particularly those that require refrigeration.

Title
Photoactivatable time-temperature indicator
Application Number
6/786407
Publication Number
4737463
Application Date
October 9, 1985
Publication Date
April 12, 1988
Inventor
Ronald R Chance
Morris Plains
NJ, US
Thaddeus Prusik
Roosevelt
NJ, US
James T Yardley
Morristown
NJ, US
Himangshu R Bhattacharjee
Randolph
NJ, US
Agent
Arthur J Plantamura
Assignee
LifeLines Technology
NJ, US
IPC
G01D 21/00
G01N 33/02
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