FLEXIBLE PACKAGING
z Bobst AluBond – a breakthrough in high metal adhesion
Flexible packaging in India – cost-effective , sustainable solutions
Naresh Khanna
The past two years have been active growth periods for the Indian flexible packaging industry . While the pandemic seems to have spurred the overall growth of hygienically packed products , the investments in large film lines point to significant long-term growth for flexible packaging . However , sustainable laminate structures that are cost-effective are crucial to survival in the future . Although several approaches are discussed daily , the one that has found favor with many film manufacturers and flexible packaging converters is the use of vacuum metalized films .
The more than dozen film lines ordered by Indian companies in 2020 , amounting to more than 20 % of the order intake of the largest global manufacturer in that year , have begun installation this year . In addition , a large number of gravure and CI flexo presses and laminators were installed and commissioned in 2020 . Significantly , more than a dozen vacuum metalizers were also commissioned in 2020 , and most were from Bobst .
In the first eight months of the current year , more than a dozen vacuum metalizers are already on order , and the pace will likely continue . Therefore , it is safe to say that in the two calendar years of 2020 and 2021 , the Indian market will absorb more than 30 vacuum metalizers . Driving this investment is the need to improve the oxygen and moisture barrier of a variety of films with a good deposition of metal and also to try and avoid the cost of an extra film layer or coating .
Of the Bobst Expert K5 vacuum metalizers that came last year and are already ordered this year , an extraordinary number ( an estimated 90 %) contain Bobst ’ s AluBond technology . Other manufacturers have also sold their vacuum metalizers into the Indian market with similar technologies for superior metal adhesion to film substrates .
A common problem in film structures for flexible packaging is poor metal adhesion due to de-lamination . Traditional metalization , even with plasma treatment , can result in poor metal to polymer substrate bonding . This produces delamination , which leads to packaging failure and results in product rejects and loss of reputation .
Developed initially for polyester films , AluBond is now increasingly used with BOPP and PE films to provide the oxygen and moisture barrier properties required , especially for food packaging that is more easily recyclable . We are familiar with many Indian companies that have invested in the technology , including Sparsh Industries , SRF and Constantia – all three which we have written about .
The problem is low surface energy on the metal side , contributing to poor lamination bonding . In addition , there is increasing demand in the industry for higher levels of metal adhesion on metalized film due to the need for more complex packaging structures , which requires a lamination peel strength suitable for functional needs . This attribute is easily tested using the standard tape test .
Low surface energy on the metal side , contributes to poor lamination bonding which is easily tested using the standard tape test . Photo Bobst
28 Packaging South Asia 5 October 2021