Patent ID: 6325974
Filing Date: 2001-12-04
Classification: B65D,G01N

Abstract:
A package (1) for decayable foodstuffs (2) comprising:packaging material (3) forming a generally closed package space (4) for receiving a foodstuff, at least a portion of said packaging material being gas permeable; andan indicator device for said package positioned on said package material,said indicator device having;an interior wall (10) andan exterior wall (8), said exterior wall forming, with said interior wall, a generally closed indicator space outside said packaging material, said indicator space containing an indicator (6),said exterior wall being exposed to an environment for the package and formed of a material (9) having a temperature dependent and controllable gas permeability to allow gas to pass through the exterior wall into said indicator space in a desired manner related to temperature and the length of environmental exposure time to which the package is subjected;said interior wall (10) of said indicator device adjoining the package space (4), said interior wall being formed of a material controllable permeable to gas so that gas entering into and/or generated in the package space can penetrate from the package space into the indicator space in a desired manner;said indicator (6) being responsive to the gas passing through said exterior wall from the environment for indicating the temperature and exposure time dependent ageing of the package, said indicator further being responsive to gas passing through said interior wall from said package space for indicating the presence of gas in the package space,whereby said indicator can simultaneously indicate package ageing, temperature dependent ageing, leakage occuring in said package space, and decay of foodstuffs in said package space.an indicator device for said package positioned on said packaging material,said indicator device having;an interior wall (8) andan exterior wall (10), said exterior wall forming, with said interior wall, a generally closed indicator space outside said packaging material, said indicator space containing an indicator (6),said exterior wall being exposed to an environment for the package and formed of a material (9) having a temperature dependent and controllable gas permeability to allow gas to pass through the exterior wall into said indicator space in a desired manner related to temperature and the length of environmental exposure time to which the package is subjected;said interior wall (10) of said indicator device adjoining the package space (4), said interior wall being formed of a material controllable permeable to gas so that gas entering into and/or generated in the package space can penetrate from the package space into the indicator space in a desired manner;said indicator (6) being responsive to the gas passing through said exterior wall from the environment for indicating the temperature and exposure time dependent ageing of the package, said indicator further being responsive to gas passing through said interior wall from said package space for indicating the presence of gas in the package space,whereby said indicator can simultaneously indicate package ageing, temperature dependent ageing, leakage occurring in said package space, and decay of foodstuffs in said package space.