Time-temperature indicator composition
US4298348A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 3, 1980 |
| Grant date | Nov 3, 1981 |
| Priority date | — |
| Expiry date | Mar 3, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N31/229
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved recording device is described, useful for measuring the integrated time-temperature or integrated radiation-dosage history of an article, comprising a substrate onto which 2,4-hexadiyn-1,6-diol-bis-(p-chlorobenzenesulfonate) is deposited. The inactive form is capable of being converted by melt recrystallization to an active form, which undergoes 1,4-addition polymerization resulting in an irreversible, progressive color change. The color change produced at any given point in time represents an integrated time-temperature history of thermal annealing or integrated radiation-dosage history of exposure to actinic radiation to which an article has been exposed. Also described is a process for converting an inactive form of 2,4-hexadiyn-1,6-diol-bis(p-chlorobenzenesulfonate) to its active form by thermal recrystallization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.