Insulated double-walled disposable plastic cup

Abstract

A thermally insulated double-walled disposable plastic container includes a container body having an inner cup and outer cup fixedly separated by an insulating space. The thermally insulated double-walled disposable plastic container is open at the top and enclosed at the bottom. The insulating space includes a gas for providing thermal insulation. A preferred gas is air. Preferred methods for making the insulated disposable double-walled plastic container includes blow-molding, thermoforming or injecting molding an inner cup and outer cup then fixedly connecting the inner cup and outer cup to define an insulation space there between.

1 . A thermally insulated disposable plastic container, comprising:
 i. a plastic outside wall having a thickness of about 0.005 to about 0.030 inches;   ii. a plastic inside wall having a thickness of about 0.001 to about 0.012 inches   iii. an insulation layer sandwiched between said plastic outside wall and said plastic inside wall; and   iv. a plastic base closure connected to a bottom portion of said plastic outside wall and said plastic inside wall, whereby said plastic outside wall and said plastic inside wall cooperate to define a an insulation layer having a thickness of about 0.025 to about 0.250 inches there between for providing thermal insulation for any material disposed within said container and wherein said insulation layer comprises a gas.   
   
   
       2 . The container of  claim 1 , wherein said gas comprises air, nitrogen, pentane, hydrocarbon gas or combinations thereof. 
   
   
       3 . The container of  claim 1 , wherein at least said plastic outside wall and said plastic inside wall have a transparency value of from about 80 to 100%. 
   
   
       4 . The container of  claim 1 , wherein at least said plastic outside wall and said plastic inside wall are translucent. 
   
   
       5 . The container of  claim 1 , wherein said plastic outside wall and said plastic inside wall are attached by a process comprising welding, ultrasonic welding, chemical adhesives, rim rolling, snap fit sealing or a combination thereof. 
   
   
       6 . The container of  claim 1 , further comprising one or more circular horizontal ribs, rectangular vertical ribs or a combination thereof formed between the said plastic inside wall and said plastic outside wall. 
   
   
       7 . The container of  claim 1 , wherein said plastic base closure is double-walled and is defined by said plastic inside wall and said plastic outside wall. 
   
   
       8 . A double-walled disposable cup comprising an outer cup and an inner cup formed of a polymer based material, said inner cup and said outer cup coming together near or at an upper rim of said cup to form an annular space there between, wherein said inner cup has a wall thickness of from about 0.001 to about 0.012 inches, said outer cup has a wall thickness of about 0.005 to about 0.030 inches and said annular space is about 0.025 to about 0.250 inches wide. 
   
   
       9 . The double-walled cup of  claim 8  wherein at least one of said inner cup or said outer cup is tapered toward the other in a section of the cup below where said inner cup and said outer cup come together. 
   
   
       10 . The double-walled cup of  claim 8  wherein said inner cup and said outer cup are substantially parallel before coming together near said upper rim of said cup. 
   
   
       11 . The double-walled cup of  claim 8  wherein said inner cup and said outer cup form said rim of said cup. 
   
   
       12 . The double-walled cup of  claim 11  wherein the inner cup and outer cup both have an overhang rim that are rolled together to form a unitary curled rim for said cup. 
   
   
       13 . The double-walled cup of  claim 8  wherein an upper section of said outside cup near said rim comprises at least one locking protrusion for engaging an upper section of said inside cup near said rim, whereby said at least one locking protrusion slopes inwardly and downwardly of said upper section of said outside cup to provide an engagement section for said inner cup; and wherein a section of said inner cup is formed to extend above and over the top of the outer cup and further extending downwardly to engage said at least one locking protrusion of the outer cup via an inner protrusion of said inner cup that slopes inwardly and downwardly to engage and seal with the at least one locking protrusion. 
   
   
       14 . The double-walled cup of  claim 13 , wherein an upper section of said outside cup near said rim further comprises a second locking protrusions for engaging a lid. 
   
   
       15 . The double-walled cup of  claim 8  wherein both said inner cup and said outer cup are transparent or translucent. 
   
   
       16 . The double-walled cup of  claim 8 , wherein said polymer based material comprises polypropylene, polyethylene terephthalate, polylactic acid, polystyrene or a combination thereof. 
   
   
       17 . The double-walled cup of  claim 8 , wherein said annular space is divided into at least four equal parts having at least two double-walled portions. 
   
   
       18 . The double-walled cup of  claim 17 , wherein said at least four equal parts alternate between double-walled and single walled sections. 
   
   
       19 . A method of forming a double-walled disposable plastic cup comprising the steps of:
 i. forming an outer cup having a wall thickness of about 0.005 to about 0.030 inches   ii. forming an inner cup having a wall thickness of from about 0.001 to about 0.012 inches   iii. fixedly attaching said inner cup and said outer cup together near or at an upper rim of said cup and forming a space comprising a gas between said inner cup and said outer cup, wherein said space is about 0.025 to about 0.250 inches thick.   
   
   
       20 . The method of  claim 19 , wherein said step of forming said outer cup comprises blow molding an outer bottle from a thermoplastic polymer and trimming said outer bottle to form said outer cup; or said step of forming said inner cup comprises blow molding an inner bottle from a thermoplastic polymer and trimming said inner bottle to form said inner cup. 
   
   
       21 . The method of  claim 19 , wherein said step of fixedly attaching said inner cup and said outer cup comprises welding, ultrasonic welding, chemical adhesion, rim rolling, snap fit sealing or a combination thereof. 
   
   
       22 . The method of  claim 19 , wherein at least said step of forming said outer cup or forming said inner cup comprises thermoforming. 
   
   
       23 . The method of  claim 20 , wherein at least one of said step of forming said outer cup or forming said inner cup comprises injection molding and wherein at least one of said step of forming said outer cup or forming said inner cup comprises a blow molding process.