HEAT-SEALABLE HYDROXYETHYL CELLULOSE FILM AND PROCESS FOR PREPARING SAME

摘要

When hydroxyethyl cellulose (HEC) films are treated with a solution of a hydrophobic film former such as polyvinylidene chloride copolymers or nitrocellulose in a volatile solvent to produce a heat sealable coating on the surface of the film, the adhesion between the HEC and the hydrophobic film former is improved by passing the HEC gel film through a conditioning bath containing from about 0.3 to 2.0 percent by weight (based on total bath weight) of a water soluble block copolymer of polyoxyethylene and polyoxypropylene prior to drying the film and applying hydrophobic film former solution thereto.