Color-retaining excess-temperature exposure indicator
US7517146B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 24, 2007 |
| Grant date | Apr 14, 2009 |
| Priority date | — |
| Expiry date | Aug 24, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01K3/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An excess temperature indicator can provide a visual indication of past exposure of perishable, maturing and other host products to an elevated temperature exceeding a threshold temperature. The indicator can have an upper layer provided with a viewing window and a wick attached to the upper layer. A reservoir of heat-fusible indicator material can be disposed in contact with the wick, to fuse and move along the wick changing the visual appearance of a first portion of the wick viewable through the window, in response to an excess temperature event. Also, the indicator can have a region of fused upper layer material attaching the wick to the upper layer. Optionally, a window seal can extend around the viewing window to prevent migration of the indicator material. The indicator can be employed to monitor vaccines, foods and other products providing an enduring visual signal of exposure to potentially damaging temperature conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.