Insulated panels and shipping container incorporating said panels

Abstract

The invention relates to an insulation panel for use in thermally insulated shipping containers, the panel comprising a rigid core of an insulation material, the core being wholly encompassed within a polyethylene foam envelope. A container made from the panels and a shipping carton is also described.

1 . An insulation panel for use in thermally insulated shipping containers, the panel comprising a rigid core of an insulation material, the core being wholly encompassed within a polyethylene foam envelope.  
   
   
       2 . The insulation panel of  claim 1  wherein the core comprises a foam block of one of polyurethane and polystyrene or polyethylene terephalate.  
   
   
       3 . The insulation panel of  claim 1  wherein the core is a closed cell polyethylene foam.  
   
   
       4 . The insulation panel of  claim 1  wherein the core is a non-cross-linked polyethylene foam.  
   
   
       5 . The insulation panel  claim 1  wherein the panel has an inner surface, an outer surface and edge surfaces, the inner and outer surfaces comprising a layer of polyethylene foam, the density of the polyethylene foam forming the inner surface being greater than the density of the polyethylene foam forming the outer surface. Preferably the thickness of the polyethylene foam forming the inner surface is less than the thickness of the polyethylene foam forming the outer surface.  
   
   
       6 . A thermally insulated container which includes at least one insulation panel of  claim 1 .  
   
   
       7 . The insulated container of  claim 6  which includes a plurality of the above insulation panels assembled into a square or rectangular box with interconnecting sides and a closed bottom.  
   
   
       8 . An insulated shipping container which includes at least one thermally insulated container of  claim 6 .  
   
   
       9 . The insulated shipping container of  claim 8  which also includes a reinforced cardboard carton.  
   
   
       10 . A process for the manufacture of a thermally insulated container comprising the steps of: 
 (i) providing a first, second, third and fourth rectangular polyethylene foam sections, each section having two opposed ends;    (ii) joining the sections together at or near the ends of the sections so to provide a substantially square or rectangular frame;    (iii) providing a fifth polyethylene foam section and joining the frame and the fifth section together so to provide a container having a closed bottom and a cavity therein;    (iv) providing insulation material and locating the material within the cavity so to fill or substantially fill the cavity;    (v) providing a sixth polyethylene foam section and joining the container and the sixth section together to close the container and provide the thermally insulated container.    
   
   
       11 . The process of  claim 10  wherein the sections are joined together with airtight joints.  
   
   
       12 . The process of  claim 11  wherein the sections are joined together by heat welding.  
   
   
       13 . A process for the manufacture of a thermally insulated container wherein a plurality of insulation panels of  claim 1  are joined together to provide an insulated shipping container.  
   
   
       14 . The process of  claim 13  wherein the panels are joined together with airtight joints.  
   
   
       15 . The process of  claim 14  wherein the panels are joined together by heat welding.  
   
   
       16 . A process for the manufacture of a thermally insulated container, the process comprising the steps of: 
 (i) providing a first, second, third, fourth, fifth, and sixth rectangular polyethylene foam sections, each section having two opposed ends, each panel comprising a rigid core of an insulation material, the core being wholly encompassed within a polyethylene foam envelope;    (ii) joining the first, second, third, and fourth sections together at or near the ends of the sections so to provide a substantially square or rectangular frame;    (iii) joining the frame and the fifth section together so to provide a container having a closed bottom and a cavity therein;    (iv) providing the sixth polyethylene foam section to close the container thus providing the thermally insulated containers.    
   
   
       17 . The process of  claim 10  further comprising the step of joining together with airtight joints.  
   
   
       18 . The process of  claim 16  further comprising the step of joining the sections together by heat welding.