Method of manufacturing a flexible film container

Abstract

A method of manufacturing a flexible film container ( 10 ) from a flexible sheet of thermoplastic material. A gaseous mixture of fluoride gas and nitrogen gas is then introduced into the interior of the flexible film container, thereby expanding the flexible film container to an inflated configuration. The gaseous mixture is maintained within the flexible film container for approximately 15 seconds to 2 minutes so as to react to form a fluorinated barrier layer or surface. The fluoride gas is then removed from the flexible film container and the flexible film container is deflated to a collapsed configuration. The deflated flexible film container is then provided with a final seal and flattened for final shipment.

1 . A method of manufacturing a flexible film container comprising the steps of:
 (A) providing a flexible thermoplastic sheet;   (B) forming a flexible film container from the flexible thermoplastic sheet;   (C) introducing a gaseous mixture of fluoride gas and at least one second gas into the interior of the flexible film container to expand the flexible film container to an inflated configuration;   (D) maintaining the gaseous mixture within the flexible film container a sufficient time to cause the interior surface of the flexible film container to become fluorinated, and   (E) removing the gaseous mixture from within the flexible film container to cause the flexible film container to deflate from the inflated configuration to a collapsed configuration.   
     
     
         2 . The method of  claim 1  wherein the second gas is an inert gas. 
     
     
         3 . The method of  claim 2  wherein the inert gas is nitrogen gas. 
     
     
         4 . The method of  claim 1  wherein the gaseous mixture is no more than 20% fluoride gas. 
     
     
         5 . The method of  claim 1  wherein the gaseous mixture is no less than 3% fluoride gas. 
     
     
         6 . The method of  claim 1  wherein the gaseous mixture is generally 5% to 10% fluoride gas. 
     
     
         7 . The method of  claim 6  wherein the second gas is nitrogen gas. 
     
     
         8 . The method of  claim 1  further comprising the step of (F) flattening the flexible film container for shipping purposes. 
     
     
         9 . The method of  claim 1  wherein step (E) the removing of the gaseous mixture includes flushing the interior of the flexible film container with a fluorine fee gas, and subsequently removing substantially all of the remaining gas within the flexible film container. 
     
     
         10 . A method of manufacturing a flexible film container comprising the steps of:
 (A) providing an unfluorinated, flexible thermoplastic sheet;   (B) forming the unfluorinated, flexible thermoplastic sheet into a flexible film container;   (C) coupling a gas dispensing tube to the flexible film container;   (D) flowing a gaseous mixture containing fluoride gas through the gas dispensing tube and into the flexible film container;   (E) maintaining the gaseous mixture within the flexible film container to cause the interior surface of the flexible film container to become fluorinated;   (F) removing the gaseous mixture from within the flexible film container;   (G) collapsing the flexible film container, and   (H) removing the gas dispensing tube from the flexible film container.   
     
     
         11 . The method of  claim 10  wherein step (F) the removing of the gaseous mixture includes flushing the interior of the flexible film container with a fluorine free gas, and subsequently removing substantially all of the remaining gas within the flexible film container. 
     
     
         12 . The method of  claim 10  wherein the gaseous mixture includes an inert gas. 
     
     
         13 . The method of  claim 12  wherein the inert gas is nitrogen gas. 
     
     
         14 . The method of  claim 10  wherein the gaseous mixture is no more than 20% fluoride gas. 
     
     
         15 . The method of  claim 10  wherein the gaseous mixture is no less than 3% fluoride gas. 
     
     
         16 . The method of  claim 10  wherein the gaseous mixture is generally 5% to 10% fluoride gas. 
     
     
         17 . The method of  claim 16  wherein the second gas is nitrogen gas. 
     
     
         18 . The method of  claim 1  further comprising the step of (I) compressing the flexible film container for shipping purposes. 
     
     
         19 . A method of manufacturing a flexible film container comprising the steps of:
 (A) providing a flexible polyethylene sheet;   (B) forming a flexible polyethylene film container from the flexible polyethylene sheet;   (C) inflating the flexible polyethylene film container by introducing a mixture of fluoride gas and at least one other gas into the interior of the flexible polyethylene film container;   (D) maintaining the mixture within the flexible polyethylene film container to fluorinate the interior surface of the flexible polyethylene container, and   (E) expelling the mixture from within the flexible polyethylene film container to cause the flexible polyethylene film container to fully or near-fully collapse.   
     
     
         20 . The method of  claim 19  wherein step (E) the expelling of the mixture includes flushing the interior of the flexible polyethylene film container with a fluorine fee gas, and subsequently removing generally the remaining gas within the flexible polyethylene film container.