Tear-resistant low set elastic film and method of making

• Main Authors: MIDDLESWORTH JEFFREY A, CREE JAMES W, BRUCE STEVE D
• Format: Patent
• Language: English
• Published: 23.01.2003
• Edition: 7
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BANDAGES, DRESSINGS OR ABSORBENT PADS; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FOMENTATION; HUMAN NECESSITIES; HYGIENE; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; MEDICAL OR VETERINARY SCIENCE; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PERFORMING OPERATIONS; PROSTHESES; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; TREATMENT OR PROTECTION OF EYES OR EARS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A tough low set elastic film exhibiting surprisingly high tear resistance and method of making the same. The film of the invention is especially beneficial when holes form on the films during manufacturing or normal wear and method of making. The film has activated and non-activated zones formed during an activation process. The activated zones allow the film to expand without generating excessive tensional forces. The film has M-polypropylene or M-polyethlyene skin layers and a core layer having an elastomeric polyurethane, ethylene copolymer such as ethylene vinyl acetate, an ethylene/propylene copolymer elastomer or ethylene/propylene/diene terpolymer elastomer. The activation process allows the skin layers to behave more like the core layer.