Packaging container and method of producing the same

Abstract

A packaging container according to the present invention is molded of a thin synthetic resin sheet. The outer peripheral edge of an opening of the packaging container 1, 18 has an outwardly extemded flange 11 . The outer peripheral edge 11 a of the flange 11 is corrugated in the vertical or horizontal direction. By corrugating the outer peripheral edge 11 a of the flange 11 , the corrugated outer peripheral edge 11 a can give a soft touch to user's hand or finger or a wrapping film contacting the same. As a result, user's hand or finger can be prevented from being hurt and the wrapping film can be prevented from being broken.

1 . A packaging container molded of a synthetic resin sheet in a predetermined shape, a peripheral edge encompassing an opening of the packaging container being corrugated.  
   
   
       2 . A packaging container according to  claim 1 , in which the difference between the top and the bottom of the waveform of the corrugation is in the range of 0.2-1.0 mm and the pitch (the distance between the tops or the bottoms of the waveforms) of the corrugation is in the range of 0.5-5.0 mm.  
   
   
       3 . A packaging container according to  claim 2 , in which the difference between the top and the bottom of the waveform of the corrugation is not more than 0.5 mm and the pitch (the distance between the tops or the bottoms of the waveforms) of the corrugation is not more than 1.0 mm.  
   
   
       4 . A packaging container according to  claim 1 , in which an outer peripheral edge of the packaging container is corrugated by providing minute projections and minute recesses throughout a flange formed at the periphery of the opening of the packaging container and then cutting the outer periphery of the flange provided with the minute projections and the minute recesses.  
   
   
       5 . A method for manufacturing a packaging container including 
 a step of molding a synthetic resin sheet into a predetermined shape using a metal mold for vertically corrugating a part outwardly projected from an opening of the packaging container, and    a step of transferring the sheet-molded product obtained in the above-mentioned step to a trimming die and cutting the peripheral edge encompassing the opening using a cutting blade having a blade edge which is straight or corrugated in the direction of the length of the blade.    
   
   
       6 . A method for manufacturing a packaging container according to  claim 5 , in which the step of cutting using the cutting blade is carried out in an atmosphere temperature range of 15° C.-55° C.  
   
   
       7 . A packaging container according to  claim 2 , in which an outer peripheral edge of the packaging container is corrugated by providing minute projections and minute recesses throughout a flange formed at the periphery of the opening of the packaging container and then cutting the outer periphery of the flange provided with the minute projections and the minute recesses.  
   
   
       8 . A packaging container according to  claim 3 , in which an outer peripheral edge of the packaging container is corrugated by providing minute projections and minute recesses throughout a flange formed at the periphery of the opening of the packaging container and then cutting the outer periphery of the flange provided with the minute projections and the minute recesses.