Back to results
US 11,472,085 B2Granted
Gas-permeable barrier film and method of making the gas-permeable barrier film
AssigneeBerry Plastics Corporation
InventorsVadim G. Zaikov, Jeffrey A. Middlesworth, Bradley Sonnentag, Brooke D. Kitzmiller
Life of this patent
Estimating the term…
Abstract
Gas-permeable barrier films include a polyolefin and an inorganic filler dispersed in the polyolefin. Methods for forming polymeric films and articles of manufacture prepared therefrom are described.
Claims24
A process for making a gas-permeable barrier film comprising the steps of
- extruding a composition that comprises a polyolefin and an inorganic filler to form a molten web, the inorganic filler having an average particle size less than about 9.5 microns,
- casting the molten web against a surface of a chill roll to form a quenched film, wherein the molten web is configured to hit the surface of the chill roll within a distance of less than about 3 inches, and
- stretching the quenched film to form a gas-permeable barrier film having a Gurley porosity of less than about 300 seconds and a basis weight of between about 60 gsm and about 100 gsm, wherein the stretching comprises cross-directional intermeshing gear (CD-IMG) stretching and machine direction (MD) stretching, wherein at least a portion of the stretching is performed at a temperature of between about 60 degrees Fahrenheit and about 225 degrees Fahrenheit, and wherein the MD stretching occurs after the CD-IMG stretching.
A process for making a gas-permeable barrier film comprising the steps of
- extruding a composition that comprises polyethylene, polypropylene, or a combination thereof and an alkaline earth metal carbonate to form a molten web, the alkaline earth metal carbonate comprising at least about 50% by weight of the gas-permeable barrier film,
- casting the molten web against a surface of a chill roll under negative pressure by a vacuum box to form a quenched film, wherein the molten web is configured to hit the surface of the chill roll within a distance of less than about 3 inches,
- stretching the quenched film by cross-directional intermeshing gear (CD IMG) stretching followed by post-stretching in a machine direction to form a gas-permeable barrier film having a Gurley porosity of less than about 300 seconds and a basis weight of between about 70 gsm and about 80 gsm, wherein at least a portion of the stretching is performed at a temperature of between about 60 degrees Fahrenheit and about 225 degrees Fahrenheit, and
- annealing the gas-permeable barrier film at a temperature of between about 75 and about 225 degrees Fahrenheit.
1 more element
A process for making a gas-permeable barrier film comprising the steps of
- extruding a composition that comprises a polyolefin and an inorganic filler to form a molten web, the inorganic filler having an average particle size less than about 9.5 microns,
- casting the molten web against a surface of a chill roll to form a quenched film, wherein the molten web is configured to hit the surface of the chill roll within a distance of less than about 3 inches, and
- stretching the quenched film to form a gas-permeable barrier film having a Gurley porosity of less than about 300 seconds, wherein the stretching comprises cross-directional intermeshing gear (CD-IMG) stretching and machine direction (MD) stretching, wherein the MD stretching occurs after the CD-IMG stretching, wherein at least a portion of the stretching is performed at a temperature of between about 60 degrees Fahrenheit and about 225 degrees Fahrenheit, and wherein the gas-permeable barrier film has a basis weight of between about 60 gsm and about 100 gsm.
Dependencies are inferred from the claim text.