04892677 is referenced by 28 patents and cites 17 patents.

A new process is described which is useful for producing novel articles of manufacture useful for monitoring the time-temperature history of perishable items. The process initially involves forming a solution comprised of a diacetylenic monomer and a solvent. The solution is frozen, and the frozen solution having crystalline diacetylenic monomer therein is irradiated to partially polymerize the diacetylenic monomer. Partial polymerization of the crystalline diacetylenic monomer admixed with frozen solvent results in the production of a novel article of manufacture having color. The novel article of manufacture is comprised of frozen solvent, diacetylenic monomer, and colored polydiacetylene. Due to the intensity of the color of the polydiacetylene, the entire article of manufacture appears to be colored.

The colored article of manufacture may be attached to various perishables to monitor the shelf life of the perishables. upon exposure to temperatures above a critical temperature, the frozen solvent melts and extracts unreached monomer from the colored polymer, thereby causing a sharp color transition which indicates that the perishable should possibly be discarded.

Title
Defrost indicator
Application Number
373955
Publication Number
4892677
Application Date
December 19, 1984
Publication Date
January 9, 1990
Inventor
Ray H Baughman
Morris Plains
NJ, US
Thaddeus Prusik
Roosevelt
NJ, US
Anthony F Preziosi
Ledgewood
NJ, US
Agent
Arthur J Plantamura
Assignee
LifeLines technology
NJ, US
IPC
G01D 21/00
G01N 31/00
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