Package Valve System

Abstract

A valve system for a container ( 4, 5 ), especially for food containers whose contents are intended to be heated, comprises an adhesive layer ( 3 ) arranged over an opening portion ( 6 ) in the container ( 4 ). The adhesive layer ( 3 ) is arranged to at least partly release the container ( 4 ) adjacent an opening portion ( 1 ) in the adhesive layer in case of overpressure and thus form an opening to allow a flow out of the container ( 4, 5 ) and, in this flowing-out, emit an acoustic signal by means of said opening portion ( 1 ) in the adhesive layer ( 3 ) which is made to oscillate by the flow. The valve system comprises at least a second opening portion ( 2 ) arranged, in heating of the contents of the container ( 4, 5 ), to open before the above-mentioned opening portion ( 1 ) in the adhesive layer ( 3 ).

1 . A valve system for a container, especially for food containers whose contents are intended to be heated, said valve system comprising an adhesive layer arranged over an opening portion in the container, the adhesive layer being arranged to at least partly release the container adjacent an opening portion in the adhesive layer in case of overpressure and thus form an opening to allow a flow out of the container and, in this flowing-out, emit an acoustic signal by means of said opening portion in the adhesive layer which is made to oscillate by the flow, wherein
 the valve system comprises at least a second opening portion arranged, in heating of the contents of the container, to open before the above-mentioned opening portion in the adhesive layer.   
   
   
       2 . A valve system as claimed in  claim 1 , in which said second opening portion is arranged in the adhesive layer. 
   
   
       3 . A valve system as claimed in  claim 2 , in which said second opening portion comprises a slit in the adhesive layer. 
   
   
       4 . A valve system as claimed in  claim 3 , in which the slit is straight. 
   
   
       5 . A valve system as claimed in  claim 4 , in which slits are aligned with each other. 
   
   
       6 . A valve system as claimed in  claim 1 , in which the opening portion of the container is a slit. 
   
   
       7 . A valve system as claimed in  claim 1 , in which said second opening portion is arranged closer to the opening portion in the container than said first opening portion in the adhesive layer. 
   
   
       8 . A valve system as claimed in  claim 1 , in which said second opening portion is arranged to close when said first opening portion in the adhesive layer opens. 
   
   
       9 . A valve system as claimed in  claim 1 , in which at least part of the container is perforated. 
   
   
       10 . A valve system as claimed in  claim 1 , in which said second opening portion consists of perforations in the container. 
   
   
       11 . A valve system as claimed in  claim 1 , in which the adhesive layer is resealable. 
   
   
       12 . A valve system as claimed in  claim 1 , in which said first opening portion comprises a flap in the adhesive layer.