Clay-filled polymer barrier materials for food packaging applications

摘要

The specification discloses a layered composite containing a barrier layer comprising clay homogeneously dispersed in a continuous phase of polymeric material. The barrier layer is especially useful in the manufacture of liquid food containers. The clay/polymer barrier layer is formed by dispersing the clay in molten polymeric material to form a homogeneously dispersed clay in a continuous polymer phase. The barrier layer is then applied adjacent one surface of a paperboard component of the composite at a thickness ranging from about 1 to 30 microns. The paperboard may be coated or uncoated at the time the barrier layer is applied, and additional polymeric barrier layers and tie or adhesive layers may be used in combination with the barrier layer to provide reduced oxygen and water vapor transport through the composite. The method of preparing and applying the barrier layer to a paperboard substrate also significantly reduces process steps required to provide coated paperboard with improved barrier properties.