Summit on sleeves

Although the technology has been around in Japan since the 1960s, shrink sleeves were pioneered in the West more than 30 years later by Lucozade. Christian Mueller, divisional head of packaging development for brand owner GlaxoSmithKline, described the effect on sales at the recent AWA International Sleeve Label Conference in Amsterdam.

“In 1994 we had a glass bottle with a paper sleeve, then in 2000 we used a PVC sleeve on a glass bottle, then a PVC sleeve on a PET bottle," he said. Annual sales soared from 150M with the introduction of the paper sleeve to the present 400M. “We realised with that success we had an environmental problem,” he added. By the end of 2007 the company will be using polyolefin based film for all sleeves to ensure they separate from the bottle during recycling.

Along with technology, the size and potential of the market and environmental issues were key subjects, during the conference, which was attended by more than 120 converters and suppliers from Europe, the US and Asia. Shrink sleeves still represent only 5 per cent of the label market, according to the most recent figures, and are set to grow by both demand and application. However, opinions vary as to how much.

Seamus Lafferty, of machinery supplier Stanford Products, said: “It can still be a challenge to allay fears of traditional pressure sensitive converters that say it is too small or it is a fad.” Rates of growth vary between Japan, where it was slowing to a few per cent, and China, Mexico and South America, where it was surging by as much as 16 per cent. The sophistication of the product and the converting also varies widely.

“Different markets are at different stages along a growth curve,” he said. “There is the possibility for convergence or catch-up on the part of those markets that are still lagging.” He put Europe closer to the top of the curve, but with room for growth on all points. However, he warned that in the US five companies produce 80 per cent of all shrink sleeves.

“You need to pause and think before you enter the shrink sleeve market. Where you are is important. It may well depend on your existing business, what plant you have and the investment required, and your customers and whether you will win or lose some because you do or do not provide shrink sleeves. If you have a gravure press that can run shrink film, then you can do it quite cheaply with secondary converting equipment.”

The market is predominantly still gravure and choosing whether to buy a press from India or Italy was the most important step, he continued. “After that you need the best ingredients, as waste is the biggest problem, and you need good supplier partners and to set the highest quality standards.”

Other suppliers reiterated the need for quality, both in the printing and converting. They warned of temperature control for materials in storage and on the presses, maintaining the integrity of the seam, the need for inspection systems to check web alignment, tension and print direction to avoid poor product integrity, and to prevent distortion of the image.

Niklas Olsson, global brand manager for XSYS Print Solutions, said: “Printing sleeves is like playing golf; if you know how difficult it is you probably would never try it.” He said 90 per cent of sleeves were produced on wide web presses, but if the converter has a label background, switching to sleeves on narrow web was “quite easy” using UV flexo. Care had to be taken not to over cure and make the sleeve brittle, however, tests using UV on PVC, OPS, PET and the corn starch based PLA run at 22,500 bottles/hour were acceptable for adhesion, scratch resistance, printability, odour and gloss.

Dr Jorge Hellmann, European sales manager for Karlville Development, said developments in materials will also make the converter's work easier, such as blends, multilayers and barriers protecting foamed materials. “When you can make blends then you can shift the curve to higher shrinkages and lower temperatures. I believe that blends will be available in the near future,” he stated. With these shrinkage, will be greater than 60 per cent at less than 90degC.

One new material, the maize derivative PLA, is moving from R&D to upscaling, according to Bart De Keyer, general manager of producer Sidaplax. He said PLA is on the brink of a breakthrough now that it is becoming available commercially and, because of increased volumes and more expensive oil based resins, the price was competitive with PET.

While standard shrink application is the greater part of the plastics sleeves market, developments in roll on/shrink on sleeves and stretch sleeves were also revealed. Tarquin Crouch, labels market segment manager for ExxonMobil business films, said the sleeving method used on Actimel attained shrinkages of 14-19 per cent and developments in ultrasonic and laser seal labelling could reduce the cost. It was also hoped to achieve 45 per cent shrinkage to include more product lines, such as soft drinks.

Stretch sleeves were promoted by Alexandre Canetti, a key account manager for Autobar Flexible Packaging, as providing 40 per cent savings over shrink by eliminating glue and heat. These are used on Perrier bottles at 15 per cent stretch, but the super stretch sleeve is available at 30 per cent with high gloss and ink effects.