MULTIPLE LAYER FILMS, ITEMS UNDERSTANDING, METHODS OF MANUFACTURE OF MULTIPLE LAYER FILMS

摘要

The present invention provides multilayer films, packages formed from such films, and multilayer film production methods. in one aspect, a multilayer film comprises multilayer film comprising at least 3 layers, where each layer has opposite facial surfaces arranged in the order a / b / c, wherein layer a comprises a high density polyethylene having a mw, cc / mn, cc of at least 6.0, one mz, abs of at least 500,000 g / mol, as measured by triple detector gpc and a density of 0.957 to 0.970 g / cm3, wherein the high density polyethylene comprises at least 90 weight percent of layer a; layer b comprises a gas permeation layer,wherein an upper facial surface of layer b is in adherent contact with a lower facial surface of layer a; and layer c comprises a high density polyethylene having a mw, cc / mn, cc of at least 6.0,one mz, abs of at least 500,000 grams / mol as measured by triple detector gpc, and a density of 0.957 to 0.970 g / cm3, wherein the high density polyethylene comprises at least 90 weight percent of layer c and wherein a top face surface of layer c is in adherent contact with a lower face surface of layer b, wherein the film is machine-oriented and the film has a normalized carbon dioxide transmission rate of at least 118.11 cm³ * m / cm² / day (3,000 cc * mil / 100 in² / day), when measured according to astm f-2476 at 23 ° c, 0% relative humidity and 1 atm, and where the film has a ratio of carbon dioxide transmission rate to oxygen transmission rate of at least 4.0, when the oxygen transmission rate is measured according to astm d3985 at 23 ° c, 0% relative humidity and 1 atm.