METHOD OF REMOVING AGENTS WHICH IMPART FLAVOR AND ODOR TO PLASTIC MATERIALS Russian patent published in 1997 - IPC

FIELD: manufacture of water supply pipes, plastic containers or plastic films and envelopes for packing foodstuffs or pharmaceuticals, or for internal fixtures. SUBSTANCE: less than 0.5 wt.-% and preferably from 0.05 to 0.3 wt.-% substantially hydrophobic molecular screen from aluminium silicate with pore diameter of at least 5.5 angstrom, Si/Al molar ratio in crystalline lattice of at least 35 and preferably from 200 to 500, and sorption capacity for water at 25 C and 4.6 torr of less than 10 wt.-%, is added in molten state to plastic material. Average molecular screen particles should be preferably not greater than 5 microns. Plastic material is polyolefin-based plastic material and is preferably selected from ethylene and propylene-based plastic materials. EFFECT: more efficient removal method. 8 cl, 2 tbl