04917503 is referenced by 62 patents and cites 19 patents.

A photoactivated time-temperature indicator is based on a leuco base system. A thermally insensitive, white ("inactive") leuco base (or a mixture of such leuco bases) is mixed, preferably 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 thermally sensitive, color-forming ("active") product. 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 stored at subambient temperature.

Title
Photoactivatable leuco base time-temperature indicator
Application Number
803750
Publication Number
4917503
Application Date
September 30, 1987
Publication Date
April 17, 1990
Inventor
Himangshu R Bhattacharjee
Randolph
NJ, US
Agent
Arthur J Plantamura
Assignee
LifeLines Technology
NJ, US
IPC
G01K 11/12
G01K 3/04
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