Method of forming a polymeric foam container

Abstract

An optional venting container comprises a base and a lid. The lid is releasably latched to the base. The lid comprises at least one ventable area formed therein. The at least one ventable area is adapted to form a vent only upon a user asserting pressure thereon. The lid is made from a polymeric foam.

1 . A method of forming a polymeric foam container comprising:
 providing a foamable resin in an extruder;   extruding the foamable resin from the extruder to form an extruded material;   thermoforming the extruded material into a container including a base and a lid releasably latched to the base, the lid including at least one ventable area formed therein, the at least one ventable area having a perimeter defined by a discontinuous cut consisting of a discontinuity between opposing ends of the discontinuous cut, the opposing ends defining a hinge portion therebetween and the discontinuity spaced substantially from the hinge portion to form a single frangible portion.   
     
     
         2 . The method of  claim 1 , wherein the at least one ventable area is formed while trimming excess material from the polymeric container. 
     
     
         3 . The method of  claim 1 , wherein the discontinuous cut is formed with a sharpened tool having at least one score therein to define the discontinuity therein. 
     
     
         4 . The method of  claim 3 , further including providing a contact area to locate the at least one ventable area and receive the sharpened tool. 
     
     
         5 . The method of  claim 4 , wherein the contact area is a striker plate formed of a material having a hardness different than the sharpened tool. 
     
     
         6 . The method of  claim 1 , wherein the at least one ventable area is formed by a knife cut. 
     
     
         7 . The method of  claim 1 , wherein the container are formed from the group consisting of alkenyl aromatic polymeric foams, polyolefins foams, polyesters foams, and combinations thereof. 
     
     
         8 . The method of  claim 1 , wherein the container has a thickness of about 20 to about 150 mils. 
     
     
         9 . A method of venting a polymeric container comprising:
 providing a polymeric container including a base and a lid releasably latched to the base, the lid including at least one ventable area formed therein, the at least one ventable area having a perimeter defined by a discontinuous cut consisting of a discontinuity between opposing ends of the discontinuous cut, the opposing ends defining a hinge portion therebetween and the discontinuity spaced substantially from the hinge portion to form a single frangible portion; and   rupturing the single frangible portion of the at least one ventable area to move the at least one ventable area toward an open position.   
     
     
         10 . The method of  claim 9 , wherein the lid includes a sidewall and a top wall, the sidewall encompasses and extends generally downward from the top wall, the top wall has an angled surface located near the intersection of the top wall and the sidewall. 
     
     
         11 . The method of  claim 10 , wherein the at least one ventable area is formed in the angled surface of the top wall. 
     
     
         12 . The method of  claim 9 , wherein the at least one ventable area includes a first side and a third side with a second side disposed therebetween. 
     
     
         13 . The method of  claim 12 , wherein the hinge is disposed opposite the second side and at the termination of the first and third side. 
     
     
         14 . The method of  claim 13 , wherein the single frangible portion is disposed opposite the hinge. 
     
     
         15 . The method of  claim 9 , wherein the at least one ventable area is generally U-shaped. 
     
     
         16 . The method of  claim 9 , wherein the lid forms a plurality of ventable areas. 
     
     
         17 . The method of  claim 9 , further including the at least one ventable area remains attached to the lid in the open position. 
     
     
         18 . The method of  claim 9 , wherein a crease forms in the lid after the at least one ventable area is moved to the open position. 
     
     
         19 . The method of  claim 9 , wherein the base comprises a bottom, a sidewall and a first rim, the sidewall encompasses the bottom and extends upwardly from the bottom, the first rim encompasses the sidewall and extends generally outwardly therefrom. 
     
     
         20 . The method of  claim 19 , wherein the lid further includes a second rim, a second sidewall and a top wall, the second sidewall encompasses and extends generally downward from the top wall, the second rim extends generally outwardly from the second sidewall, the second rim of the lid is adapted to releasably latch with the first rim of the base.