Sealed Air (nz) Limited

Trigon Industries, Inc.

Robert John Whitwood

Simon Neville Balderson

Andrew Mills

Lela Margaret Monaf

Temperature sensitive material

Carbon dioxide sensitive material

A tamper evident system for indicating when a closed enclosure (24) has been opened comprises a window (21) and a sensor (22) colour sensitive to presence of a gas. The sensor (22) is located in the enclosure (24) so as to be visible through the window (21). Any compositional change of gas in the enclosure (24) is signalled by a change of colour of the sensor (22).

Tamper evident system

A gas indicator (11) for a modified atmosphere food package (19) comprises a series of strips (12, 13, 14, 15, 16) which progressively change colour as the proportion of carbon dioxide in the atmosphere progressively changes in magnitude due to absorption of the carbon dioxide by the food product (17) over time. The indicator (11) thus is 'tuned' to indicate changing atmospheric conditions inside a see-through envelope (10) and thus the condition of the product (17) can be monitored and the package (19) is tamper evident.

Gas indicator for a package

Growing community of inventors

Stafford, United Kingdom

Robert John Whitwood