Recycle-ready retortable laminated polyester-based films

Abstract

In one aspect, a pouch includes a first panel, a second panel, and a bottom gusset, wherein the first panel, second panel, and bottom gusset are formed of a polyester-based film structure and wherein the bending stiffness of the bottom gusset panel is less than or equal to 0.05 N mm. Each of the polyester-based film structures may be formed of a polyester-based polymeric composition comprising polybutylene terephthalate (PBT), polyethylene terephthalate (PET), or a blend from 0-100% by weight of PBT in PET. It is contemplated that each polyester-based film structure may comprise two or more film plies laminated to each other.

1 - 27 . (canceled) 
     
     
         28 . A polyester-based film comprising:
 a first ply comprising:
 a first layer formed of a first polyester-based polymeric composition, wherein the first polyester-based polymeric composition comprises polybutylene terephthalate, polyethylene terephthalate, or a blend thereof, the first layer having a first surface and a second surface opposite the first surface; and 
   a second ply comprising:
 a second layer, the second layer having a first surface and a second surface opposite the first surface, and wherein the second layer is formed of a sealable polyester; and 
 a third layer formed of a second polyester-based polymeric composition, wherein the second polyester-based polymeric composition comprises polybutylene terephthalate, polyethylene terephthalate, or a blend thereof; and 
   an adhesive layer interposed between the first ply and the second ply, the adhesive layer laminating the first ply to the second ply, wherein the first surface of the third layer faces the second surface of the first layer.   
     
     
         29 . The polyester-based film of  claim 28 , wherein the polyester-based film has a thickness in the range of about 9 microns to 100 microns. 
     
     
         30 . The polyester-based film of  claim 28 , wherein the second layer has a thickness in the range of about 2 microns to 25 microns. 
     
     
         31 . The polyester-based film of  claim 28 , further comprising a printed layer disposed intermediate the first layer and the adhesive layer. 
     
     
         32 . The polyester-based film of  claim 28 , wherein the first ply further comprises:
 a fourth layer formed of a ceramic coating, the fourth layer having a first surface and a second surface opposite the first surface, wherein the first surface of the fourth layer faces the second surface of the first layer; and   a fifth layer, the fifth layer interposed between the fourth layer and the adhesive layer.   
     
     
         33 . The polyester-based film of  claim 28 , wherein the second ply further comprises:
 a fourth layer formed of a ceramic coating, the fourth layer having a first surface and a second surface opposite the first surface, wherein the second surface of the fourth layer faces the first surface of the third layer; and   a fifth layer, the fifth layer interposed between the fourth layer and the adhesive layer.   
     
     
         34 . The polyester-based film of  claim 28 , wherein the polyester-based film has a seal initiation temperature of between 85° C. and 120° C. 
     
     
         35 . The polyester-based film of  claim 28 , wherein the polyester-based film is configured to form a heat seal with itself, wherein the heat seal has a seal strength in the range of about 10 N/25 mm to about 100 N/25 mm when sealed at a sealing pressure of 40 psi, a dwell time of 0.5 second, and a sealing temperature of 90-100 degrees C. 
     
     
         36 . The polyester-based film of  claim 28 , wherein the polyester-based film is configured to form an ultrasonic seal with itself. 
     
     
         37 . The polyester-based film of  claim 28 , wherein the polyester-based film is configured to form a heat seal with itself, and wherein the heat seal has a maximum seal strength in the range of about 10 N/25 mm to about 100 N/25 mm. 
     
     
         38 . The polyester-based film of  claim 28 , wherein the polyester-based film is configured to form a heat seal with itself, and wherein the heat seal has a minimum seal strength in the range of about 10 N/25 mm to about 15 N/25 mm. 
     
     
         39 . The polyester-based film of  claim 38 , wherein the minimum seal temperature to achieve said minimum seal strength is in the range of from about 115 degrees C. to about 90 degrees C. 
     
     
         40 . The polyester-based film of  claim 28 , wherein the minimum seal temperature to achieve a seal strength of at least 10 N/25 mm is in the range of from about less than or equal to 115 degrees C. to about 90 degrees C. 
     
     
         41 . The polyester-based film of  claim 28 , wherein the sealable polyester layer has a static coefficient of friction in the range of about 0.1 to 0.4 and a kinetic coefficient of friction in the range of about 0.1 to 0.4. 
     
     
         42 . The polyester-based film of  claim 28 , wherein:
 the polyester-based film has an oxygen transmission rate before undergoing a retort process in the range of about 0.1 cc/100 in 2 /day at 23 degrees C. and 0% relative humidity to about 0.05 cc/100 in 2 /day at 23 degrees C. and 0% relative humidity; and   the polyester-based film has a moisture vapor transmission rate before undergoing a retort process in the range of about 0.1 g/100 in 2 /day at 38 degrees C. and 90% relative humidity to about 0.05 g/100 in 2 /day at 38 degrees C. and 90% relative humidity.   
     
     
         43 . The polyester-based film of  claim 28 , wherein:
 the polyester-based film has an oxygen transmission rate after undergoing a retort process in the range of about 0.1 cc/100 in 2 /day at 23 degrees C. and 0% relative humidity to about 0.05 cc/100 in 2 /day at 23 degrees C. and 0% relative humidity; and   the polyester-based film has a moisture vapor transmission rate after undergoing a retort process in the range of about 0.1 g/100 in 2 /day at 38 degrees C. and 90% relative humidity to about 0.05 g/100 in 2 /day at 38 degrees C. and 90% relative humidity.   
     
     
         44 . A polyester-based film comprising:
 a first ply comprising:
 a first layer formed of a first polyester-based polymeric composition, wherein the first polyester-based polymeric composition comprises polybutylene terephthalate, polyethylene terephthalate, or a blend thereof, the first layer having a first surface and a second surface opposite the first surface; 
   a second ply comprising:
 a second layer, the second layer having a first surface and a second surface opposite the first surface, and wherein the second layer is sealable polyester layer; and 
 a third layer formed of a second polyester-based polymeric composition, wherein the second polyester-based polymeric composition comprises polybutylene terephthalate, polyethylene terephthalate, or a blend thereof; 
   a third ply comprising:
 a fourth layer formed of a third polyester-based polymeric composition, the fourth layer having a first surface and a second surface opposite the first surface; 
   a first adhesive layer interposed between the first ply and the third ply, the first adhesive layer laminating the first ply to the third ply, wherein the first surface of the fourth layer faces the second surface of the first layer; and   a second adhesive layer interposed between the second ply and the third ply, the second adhesive layer laminating the second ply to the third ply, wherein the second surface of the fourth layer faces the first surface of the third layer.   
     
     
         45 . The polyester-based film of  claim 44 , wherein the third polyester-based polymeric composition comprises polybutylene terephthalate, polyethylene terephthalate, or a blend thereof. 
     
     
         46 . The polyester-based film of  claim 44 , wherein the polyester-based film further comprises at least one of:
 a first printed layer disposed intermediate the first layer and the first adhesive layer;   a second printed layer disposed intermediate the fourth layer and the first adhesive layer;   a third printed layer disposed intermediate the fourth layer and the second adhesive layer; and   a fourth printed layer disposed intermediate the third layer and the second adhesive layer.   
     
     
         47 . The polyester-based film of  claim 44 , wherein each of the first ply, third ply, and the second ply have a thickness in the range of about 9 microns to 100 microns. 
     
     
         48 . The polyester-based film of  claim 44 , wherein the sealable polyester layer has a thickness in the range of about 2 microns to 25 microns. 
     
     
         49 . The polyester-based film of  claim 44 , wherein the first ply further comprises:
 a fifth layer formed of a ceramic coating, the fifth layer having a first surface and a second surface opposite the first surface, wherein the first surface of the fifth layer faces the second surface of the first layer; and   a sixth layer, the fifth layer interposed between the first layer and the first adhesive layer.   
     
     
         50 . The polyester-based film of  claim 44 , wherein the second ply further comprises:
 a fifth layer formed of a ceramic coating, the fifth layer having a first surface and a second surface opposite the first surface, wherein the first surface of the fifth layer faces the second adhesive layer; and   a sixth layer, the sixth layer interposed between the fifth layer and the second adhesive layer.   
     
     
         51 . The polyester-based film of  claim 44 , wherein the sealable polyester layer has a static coefficient of friction in the range of about 0.1 to 0.4 and a kinetic coefficient of friction in the range of about 0.1 to 0.4.