Packaging container for microwave oven

Abstract

A packaging container for a microwave oven. Completion of heating of the container contents and automatic opening of the container can be easily recognized. This can be achieved without requiring a special member and complex steps, but by processing wrapping materials constructing the packaging container. Also provided is a packaging container for a microwave oven, where danger, including spilling of the contents of the container and burning by touching an opening section occurring in heating by a microwave oven, can be avoided. Further provided is a packaging container for a microwave oven, sealed by heat-sealing plastic films and having a steam vent seal section having a weakened section. The steam vent seal section has mark emerging means, and when the steam vent seal section is separated and opened, the means shows different surface- and back face-wrapping materials constituting the steam vent seal section, enabling recognition of opening.

1 . A packaging container for a microwave oven hermetically sealed by heat-sealing with a plastic film, the packaging container comprising a vapor release seal part having a weakened part, 
 characterized in that the vapor release seal part is provided with a mark developing means with which exfoliation opening of the vapor release seal part can be recognized by a difference between surface and back packaging materials constituting the vapor release seal part.    
   
   
       2 . A packaging container for a microwave oven according to  claim 1 , characterized in that the mark developing means is constituted by providing a vapor release seal part of one plastic film constituting the packaging container with a printing layer having a pattern having void parts and by providing a vapor release seal part of the other plastic film constituting the packaging container with a printing layer having patterns corresponding to the void parts.  
   
   
       3 . A packaging container for a microwave oven according to  claim 1 , characterized in that the mark developing means is constituted by coloring a vapor release seal part of one plastic film constituting the packaging container a first color and by coloring a vapor release seal part of the other plastic film constituting the packaging container a second color different from the first color.  
   
   
       4 . (canceled)  
   
   
       5 . (canceled)  
   
   
       6 . A packaging container for a microwave oven according to  claim 1 , characterized in that the vapor release seal part is formed continuously along a peripheral edge seal part of the packing container.  
   
   
       7 . A packaging container for a microwave oven according to  claim 1 , characterized in that the vapor release seal part is formed separately from the peripheral edge seal part of the packing container.  
   
   
       8 . A packaging container for a microwave oven according to  claim 1 , characterized in that the vapor release seal part is provided with a through-hole, a semi through-hole, or a slit to thereby form a weakened part.  
   
   
       9 . A packaging container for a microwave oven according to  claim 1 , characterized in that a cutout is formed in the packing container inwardly into the container and a periphery edge of the cutout is heat-sealed to thereby form the vapor release seal part having a weakened part.  
   
   
       10 . A packaging container for a microwave oven according to  claim 1 , characterized in that a pouring port forming means is arranged near the vapor release seal part.  
   
   
       11 . A packaging container for a microwave oven according to  claim 1 , characterized in that the packaging container comprises a packaging pouch hermetically sealed by heat-sealing with a plastic film.  
   
   
       12 . A packaging container for a microwave oven according to  claim 11 , characterized in that the packaging pouch comprises a standing pouch.  
   
   
       13 . A packaging container for a microwave oven according to  claim 11 , characterized in that the packaging pouch comprises a packaging pouch having a branched section.  
   
   
       14 . A packaging container for a microwave oven according to  claim 1 , characterized in that the packaging container is hermetically sealed by heat-sealing of a container main body having a flange part with a lid composed of a plastic film.  
   
   
       15 . A packaging container for a microwave oven according to  claim 14 , characterized in that the vapor release seal part is formed by causing a heat-seal part between the flange part of the packaging container and the lid to project toward an inside of the container.