Metalized polyester films are increasing in popularity for their high-barrier properties in laminated flexible packaging structures. However, poor adhesion of metal to the base polyester film can result in laminate failure, thereby affecting product performance.
Films with high metal adhesion for superior barrier applications in harsh environments are currently available but they are limited and costly. As a response, Flex Films (USA) Inc. (Elizabethtown, KY) has engineered FLEXMETPROTECT F-HMB, a high-barrier metallized polyester film. The film is either untreated or corona treated on the other surface, while metalization is carried out on the specially treated composite surface. It achieves metal adhesion or bond strength greater than 1200 gram-force/in.
Flex Films is the global film manufacturing arm of India’s largest multinational flexible packaging materials company, Uflex Ltd., and all of the global Uflex plants can supply FLEXMETPROTECT F-HMB film.
Talking more about the new development, Dr. Steven J. Sargeant, General Manager, Technology, at Flex Films (USA) Inc. said, “The adhesion of metal on BOPET base film is the sum of chemical and mechanical adhesion. Our proprietary surface treatment of the base film allows increased levels of chelation or reaction with the metal being deposited, thereby resulting in a much better adhesion profile. The specialized surface treatment comprises materials with unique and enhanced properties, thereby leading to much enhanced mechanical bonding. It took us almost 18 months to engineer this film.”
Vijay Yadav, Business Head, Flex Films (USA) Inc. itemized the benefits, noting that the film offers:
- Class-leading adhesion to metal under most aggressive environmental conditions;
- improved scuff, scratch and craze resistance, thereby improving yields up to four percent and offering unparalleled robustness in processing and performance for converters;
- an OTR of 0.6 cc/m2/day at 23°C and 0% RH and MVTR of 0.6 g/m2/day at 38°C and 90% RH;
- compliance with EU and FDA regulations for food-grade applications; and
- cost effectiveness.
FLEXMETPROTECT F-HMB film finds extensive use in liquid packaging, stand-up pouch applications, bag-in-box products, chemical packaging, pharma packaging and hot-fill applications up to 80°C. The film is available in 8 to 50 micron thicknesses.
“Flex Films is focusing on specialty substrates that add real value to the business of convertors and that of their customers by enhancing the quality and profile of the resultant packaging,” said Anantshree Chaturvedi, Vice Chairman and CEO, Flex Films International. “Our expansion strategy hereafter will be niche product and not commodity driven. FLEXMETPROTECT F-HMB is a technologically superior film with encouraging demand. If we talk about the United States alone, the market for this specialized film is expected to be about 25% of the current metalized film market.”