A cut above

Keeping costs down and productivity up is paramount. Nowhere is this more true in the packaging supply chain than with slitting and rewinding. Nobody wants unnecessary downtime, especially when there is a better option. So what's new in the world of slitting and rewinding? Emma-Jane Batey spoke to industry movers and shakers to take a slice.

As a core converting process, slitting and rewinding is taken seriously. Wide machine capabilities and minimal downtime are generally the key drivers, so innovative machines largely focus on answering these issues. John Graham, managing director of Arrow Film Converters is well aware of these issues and opportunities as a provider of high-quality printed films for the food and drink industry. With his insight as a user of these systems he explained the current pressure points to Converting Today.  “It's imperative not to have a bottleneck for slitting. The quality of print and slitting has to be excellent; good is not good enough these days and for that reason we have decommissioned three of our older slitters that were only refurbished a few years ago. We replaced these with state-of-the-art slitter rewinders. While a good profile is imperative the constant tension on the rewind is equally vital. Customers have increasingly faster packaging lines and machines where, if tensions are not perfect, films will not track or might snap causing untold problems.

 When asked what was being done to minimise inefficiencies or other problems he explained, “One solution we have found to be successful is to have the slitter and rewinders with the unwind reel on the same side as our rewind reels. This allows the operator to see any joins in the mill reels and is able to slow the machine down without the need to run back and forth to the unwind section. Our machines have laser guides to improve efficiencies and can run at 600m a minute. Another area where we are seeing great strides is in material waste reduction and responsible or sustainable slitting and rewinding. As our customers are constantly pushing to reduce packaging waste, we look to our suppliers to provide us with the tools to keep films as thin as possible.What used to be 20mu is more often 15mu or less. Slitters, therefore, have to be capable of higher speeds even on relatively short runs, and be able to extract the waste trim at high speeds - even with a 5mm waste trim.”

 When asked what he felt the future held John concluded, “When we invested over £4 million a few years ago on printing presses, our oversight was on slitting and rewinding. We quickly realised our existing slitting machinery was not up to the standard we needed from the start, so I purchased two new slitters and had these delivered and commissioned within a few weeks of starting to print.. Although this only represented about 15% of the total investment, it was just as important as the printing machines. We needed to offer the full package and this allowed us to do that.”

Cut costs, cut downtime

It's not just the smaller, more nimble companies that appreciate the advantages of the latest slitting and rewinding capabilities. Major brands like Huggies have seen the value of modern machines' capabilities, as its latest Newborn four-pack of wipes shows. A collaboration between multinational personal care giant Kimberly-Clark and UK packaging manufacturer Skymark has used innovative slitting and rewinding capabilities for a practical reason.

Skymark's director Paul Neath says, “Our collaboration with Kimberly-Clark for Huggies Newborn Baby Wipes has resulted in a differentiated packaging solution that we're really proud of. We've achieved exactly what we set out to do in terms of the new film technology.” Skymark is well known for its embossed, plain and printed films, and, for this project, it developed a specially coextruded film, which increases opacity and eliminates visibility of the pack contents.

Mr Neath continues, “The project has also seen us overcome some challenging production changes. We've worked hard to solve this quickly and efficiently to ensure consistency and increased speed to market for this project and future print runs that use this method. This collaboration has brought us a step closer to being able to offer a seamless multisubstrate brand offer.” With Skymark's capabilities including cast and blown film coextrusion, solvent and solvent-less lamination and slitting, its wide range of films, bags and hygiene products benefit from its investment in the latest large-format slitting machinery. This was used in the Huggies brief with a trilayer coextruded film with a blue inner layer that disguises the pack's contents and keeps the important all-white aesthetic of the Huggies brand, enhancing its on-shelf appeal.

Man and machine

For label manufacturers, investing in state-of-the-art slitting and rewinding machinery is all-important too. Leeds-based OPM Group offers self-adhesive labels and flexible-packaging solutions, including laminates sachets, lidding film and flow wrap, and manufacturing products for many household names. The award-winning company is happy to highlight how investing in new slitting and rewinding capabilities further enhances its portfolio, as marketing director Susan Ellison explains: “We are proud of our own technical capabilities, which enable us to produce exactly what our clients ask for. We are experts in the field of peel and reseal products, with our OPM peel and reseal labels available for packaging anything from normal, aqueous to hard-to-hold products with fragrances, alcohol or germ-killing disinfectants. Our peel and reseal labels work in the same way as Peel 2 Read labels but also have a reclosing ability so they can be opened multiple times throughout the life of the product.”

OPM also prints films and laminates used to manufacture both vertical and horizontal form, creating fill and seal bags that can be made from a wide variety of materials. The flexibility of OPM's extensive knowledge uses its slitting and rewinding capabilities so that changes can be made to production with very limited downtime. Ellison adds, “Usually, very flexible films or laminates are used to form the pack, which allows for the bag to be filled with increased quantity of product when compared with a similarly sized sachet. Typically, bags are filled with dry products such as granules, powders or solid items. We ensure the choice of materials is agreed upon with our customers so that the product doesn't react with the bag material and, of course, we can offer expert advice in this area and to make sure that the material has sufficient barrier properties to protect the pack contents for a long shelf life. Our expertise in this area shines with optimum puncture resistance and aroma barrier properties, so products like ground coffee stay in peak condition. Thanks to our high-performance machines, these specific packaging solutions – for food contact, household cleaning agents or whatever – can be guaranteed with a quick turnaround.”