Corrugated structures and method for thermoforming packages

Abstract

A corrugated structure having a first flat layer, a first corrugated layer secured to the first flat layer, a second flat layer having a first side and a second side, wherein the first side is secured to the first corrugated layer on a side opposite of the first flat layer, a coating layer secured to the second side of the second flat layer, wherein the coating layer has a melting temperature of at least about 450 degrees Fahrenheit and chloroform-soluble extractives of at most about 0.5 milligrams per square inch.

1 . A corrugated structure comprising: 
 a first flat layer;    a first corrugated layer secured to said first flat layer;    a second flat layer having a first side and a second side, wherein said first side is secured to said first corrugated layer on a side opposite of said first flat layer;    a coating layer secured to said second side of said second flat layer,    wherein said coating layer is a polymeric material having a melting temperature of at least about 450 degrees Fahrenheit and chloroform-soluble extractives of at most about 0.5 milligrams per square inch.    
     
     
         2 . The structure of  claim 1  wherein said coating layer comprises polyethylene terephthalate (PET).  
     
     
         3 . The structure of  claim 2  wherein said coating layer has a coat weight range of about 8 pounds per 3,000 square feet to about 30 pounds per 3,000 square feet.  
     
     
         4 . The structure of  claim 1  wherein said coating layer comprises polymethylpentene (PMP).  
     
     
         5 . The structure of  claim 4  wherein said coating layer has a coat weight range of about 5 pounds per 3,000 square feet to about 15 pounds per 3,000 square feet.  
     
     
         6 . A container blank formed from the structure of  claim 1 .  
     
     
         7 . The structure of  claim 1  further comprising a second corrugated layer secured to said first flat layer on an opposite side from said first corrugated layer and a third flat layer secured to said second corrugated layer on an opposite side from said first flat layer.  
     
     
         8 . A corrugated structure comprising: 
 a first corrugated layer;    a first flat layer having a first side and a second side, wherein said first side is secured to said first corrugated layer;    a coating layer secured to said second side of said first flat layer,    wherein said coating layer is a polymeric material having a melting temperature of at least about 450 degrees Fahrenheit and chloroform-soluble extractives of at most about 0.5 milligrams per square inch.    
     
     
         9 . The structure of  claim 8  wherein said coating layer comprises polyethylene terephthalate (PET).  
     
     
         10 . The structure of  claim 9  wherein said coating layer has a coat weight range of about 8 pounds per 3,000 square feet to about 30 pounds per 3,000 square feet.  
     
     
         11 . The structure of  claim 8  wherein said coating layer comprises polymethylpentene (PMP).  
     
     
         12 . The structure of  claim 11  wherein said coating layer has a coat weight range of about 5 pounds per 3,000 square feet to about 15 pounds per 3,000 square feet.  
     
     
         13 . A corrugated structure comprising: 
 a first flat layer;    a first corrugated layer secured to said first flat layer;    a second flat layer having a first side and a second side, wherein said first side is secured to said first corrugated layer on a side opposite of said first flat layer;    a polymeric coating layer secured to said second side of said second flat layer.    
     
     
         14 . The structure of  claim 13  wherein said polymeric coating layer is a polymer coating suitable for food contact.  
     
     
         15 . The structure of  claim 13  wherein said polymeric coating layer is polyethylene terephthalate (PET).  
     
     
         16 . The structure of  claim 13  wherein said polymeric coating layer is polymethylpentene (PMP).  
     
     
         17 . A method for forming a container comprising the steps of: 
 providing a container blank comprising a corrugated structure having a first flat layer, a first corrugated layer secured to said first flat layer, a second flat layer having a first side and a second side, wherein said first side is secured to said first corrugated layer on a side opposite of said first flat layer, a coating layer secured to said second side of said second flat layer, wherein said coating layer has a melting temperature of at least about 450 degrees Fahrenheit and chloroform-soluble extractives of at most about 0.5 milligrams per square inch;    providing a thermoforming machine;    placing said container blank in said thermoforming machine;    transferring heat and applying mechanical forces to said heated container blank to form said blank into a container shape using said thermoforming machine.    
     
     
         18 . The method of  claim 17  wherein an outer surface of said first flat layer includes printed or graphic indicia.  
     
     
         19 . The method of  claim 17  wherein said corrugated structure is formed using flexible manufacturing techniques wherein said first flat layer, said second flat layer previously coated with said coating layer and said first corrugated layer are selected from inventory materials to form said corrugated structure that is then formed into desired container blanks.