Shrink labels have put a new twist into product packaging, as their form-fitting look catches the eye of the curious consumer.
Featuring 360° product decoration as well as tamper-evident features, shrink labels have tied the knot between product packaging and decorative labeling. This clever marriage has become a must for end users hoping to increase brand identity, through the use of containers resembling the products they represent, packaging with built-in hand grips and measuring cups, and eye-catching exotic shapes.
In the shrink label market, three basic types of material stand out from the crowd: polyvinyl chloride (PVC), polypropylene terephthalate glycol (PET-G) and oriented polypropylene (OPP) film. PVC has become known for its extremely high shrink characteristics, making it ideal for contoured containers. It is a high density film with excellent clarity, as well as grease and solvent resistance, moderate gas permeability and temperature range. Many industry professionals say its downfall, however, lies in the stigma of being less environmentally friendly. “PVC has received a certain amount of bad press due to recycling issues,” says David Hill, product manager for label films, Mobil Chemical Films Division, Macedon, N.Y., adding, “But overall PVC remains the most widely used film for the shrink label market.”
“By far the PVC sleeve has a higher shrink capability, at about 35 or 40 percent container shrinkage. However, for years there has been talk about PVC giving off some toxins,” notes Barry Hostetter, business director, AET Films, New Castle, Del. He adds that PVC is also more expensive in terms of raw material and application, as opposed to OPP film. “It’s a more well accepted, high speed, high efficiency system,” he says.
“OPP tends to lend itself to a situation for roll-fed type equipment, whereas with PVC you would need sleeve equipment,” says B.J. Anderson, product development for Salem Label Company, a major converter of OPP shrink labels headquartered in Salem, Ohio. Roll-fed OPP labels are applied with conventional roll-fed labelers with the addition of an in-line unit that uses heat guns or an oven to shrink the film. Anderson adds that OPP can also achieve higher line speeds than PVC sleeve material.
Hill of Mobil Chemical Films Division says he has observed OPP actually starting to take some of the share from the PVC market because of the cost advantage.
At similar shrink properties to PVC, but at a higher degree of recyclability, is PET-G. “PET-G is a more expensive alternative to PVC that shrinks about the same, but is more environmentally friendly,” says Hill. Similar to PVC, this material is also a high density, high strength film with excellent clarity, good abrasion resistance, moderate permeability, high dimensional stability and a wide temperature range.
As mentioned earlier, OPP is the least expensive alternative in the shrink sleeve market and the most environmentally friendly. It’s shrink capabilities, however, are lower compared with the other two films. Hill says PVC has an approximate 60 percent shrink capability, whereas OPP has upwards of 25 percent.
Lois Bruckner, director of marketing for shrink sleeve converter CMS Gilbreth, Crydon, Pa., says OPP is not recommended for use with full body sleeve applications, but rather for instances where the label will not need to cover the entire container, such as those used on Coca-Cola and similar bottles.
Mobil Chemical Films Division has changed this shrinkage downfall with the development of a new film to its “Label-Lyte” ROSO (roll-on-shrink-on) family, which Hill says has a shrink capability up to 24 percent, as opposed to its standard of 18 percent and the industry standard of 12 percent. This high-shrink clear film product, ROSO 30XL041, was recently used on Snapple beverage’s newest addition, “Hydro,” from Triarc Beverage Corp., White Plains, N.Y.
Other 18 percent machine direction (MD) shrinkable OPP ROSO products offered from Mobil include two clear films and one metalized film, and one white opaque film. These films can be used in laminations or as a single reverse-printed film (40LR200) for roll-fed labeling of contoured containers.
AET Films also offers a range of roll-fed MD shrink OPP film through its Vision shrink line, available in transparent one- and two-side treated, and opaque one- and two-side treated in various thicknesses, for a variety of applications.
From household supplies, cosmetics, and the food and beverage markets, shrink labels are setting their place in the spotlight. A simple stroll down the grocery store aisle will prove this point.
Converters provide their perspective on the growing opportunities for this heat shrinkable material. “The beverage market is very hot now,” says Sharon Lobel, president, Seal-It Inc., Farmingdale, N.Y. The dairy industry is a growing part of that share, she explains, as milk companies continue to create a more upscale and eye catching look for a product now hitting the single serve market. Some examples are the colorful appeal of Dean Foods’ “Chugs,” “My Milk” from Galliker Dairy Co., and “Moovers” from Smith Dairy Products.
The world of promotional products have also found a home for shrink labels. The advantage lies in its ability to be removed from a product once the promotion is complete, revealing the brands original label underneath. For the consumer this commemorative promotion can also have a keepsake value.
Seal-It had Irish eyes smiling at the shelves with its St. Patrick’s Day limited edition PET-G label for “Bailey’s Irish Cream Liqueur.” Reverse printed in five colors, the label was able to shrink to the contours of the bottle and reveal a 360° image area to print tasty drink recipes, a UPC code, and sparkling graphics.
Why shrink labels?
Providing bright and colorful graphics for unlimited design possibilities at maximum print areas, heat-shrinkable labels offer a number of advantages over their counterparts. “Shrink wrap is giving competition to everything. It’s a unique form of decoration. In some cases it may be because of a new container design, but in others it can replace printed metal cans. It could be any number of things for various reasons,” says Hostetter of AET Films.
When designed to cover the lid of the container, shrink sleeve labels can also provide tamper-evident protection. This added level of security provides customers with a greater amount of confidence in a product, as it is perceived as being safer and fresher.
Not only do shrink labels provide tamper evidence, but their graphic appeal has also lifted products off the shelves and into the hands of curious consumers, revealing a whole new look in product packaging. “Before, the trend was tamper evident labeling. Now this trend has moved toward a more beautiful and higher graphic appeal in addition to tamper evidence,” says Lobel. “A lot of customers have older products that have been out on the shelves for a number of years, and now want to update them and bring them up-to-date with the year 2000,” she adds.
Hostetter agrees. He says shrink wrap has allowed for more innovative and decorative containers. Once packaged in cardboard containers, drink mixes such as “Kool-Aid” and “Country Time Lemonade” have changed to plastic packaging with a colorful 360° shrink label, providing product information and tamper evidence, he explains. The container itself provides built-in hand grips and the lid acts as a measuring cup, he adds.
The ability of shrink labels to provide more information on a product is another advantage of this new age material. “With shrink material you can achieve a much larger promotional panel, as opposed to a regular film label where you are constricted to a certain area,” says Hostetter.
Full body shrink sleeve labels can provide an added benefit of UV light protection. Lobel says Seal-It recently completed a full body shrink label for a salad dressing product, which included this advantage. “The customer needed a label which prevented UV light from entering the bottle because the product included a special oil that was affected by UV light,” says Lobel. The upscale look of the label, in addition to the quality of the product itself, helped increase sales dramatically, she adds.
Shrink labels are also ideal for multiple SKU products. By applying these labels to blank containers as needed, customers are able to achieve greater flexibility and cost savings for inventory purposes. Hostetter provides the example of air freshener aerosol cans. “With shrink wrap they can inventory all aerosol cans and produce them as the volumes are needed,” he says.
With substrates as sensitive to heat as PVC, PET-G and shrinkable OPP are, printing can present challenges. “The surface of the material is very slippery, and the use of inks that are able to ‘bite’ into the film is essential,” explains Lobel. “Learning to dry the inks without using heat is another obstacle. After years of research and development, and once you have mastered these challenges and formulated the correct inks, it still remains a difficult process to accomplish.”
Seal-It prints PVC and PET-G on modified flexo and rotogravure presses, which are manufactured in-house. The company currently runs eight modified presses in a variety of widths. The average press speed is about 500-600 feet per minute. Most recently, the company added a modified 10-color rotogravure press to its 100,000 square foot facility.
“We feel that the ability to offer both flexo and rotogravure is an advantage to our customers. When the art comes in, our graphics team evaluates it. We decide which process will work — roto or flexo — and that evaluation is discussed with the customer. At Seal-It we don’t favor one process over the other, but instead we do what’s best for the project,” says Lobel.
Bruckner of CMS Gilbreth says the quality achieved on rotogravure is much higher than printed via flexo. “The quality of flexo is good, but not as good as rotogravure,” she says, adding, “It is hard to mess up a steel engraving, whereas a plate used in flexo can slip a little.” CMS Gilbreth offers both rotogravure and flexographic printing systems with four-color process capability. This ISO 9001 certified company uses water and solvent based inks, reverse prints labels to protect the images from scuffing, and employs a special process to shrink films by as much as 70 percent to ensure a perfect fit to contoured packaging.
Also in the shrinkable film market is American Fuji Seal Inc., Fairfield, N.J., which utilizes rotogravure printing up to nine colors of both line and process colors. In addition, the company manufactures its own application machinery for shrinkable films used as primary labels and tamper-evident bands.
Aside from heat issues, web tension and control are also critical when converting this extremely thin substrate. “Presses have to be carefully calibrated because the thickness of this material is much thinner,” says Bruckner. “The tension has to absolutely precise.”
Pressuring pressure sensitive?
The use of pressure sensitive labels holds its ground in the narrow web market. Although the applications may differ in some instances, many industry professionals wonder what impact heat-shrinkable labels will have on the dominant PS.
“Some pressure sensitive applications could potentially move to shrink wrap,” says Hill, adding that the overall growth of pressure sensitive is still stronger than the growth of roll-fed labeling.
Anderson provides his opinion. “There is some crossover, but the two are not directly competitive. There are some clearly defined applications for pressure sensitive and roll-fed shrink labels,” he says. Salem Label converts roll-fed shrink labels, as well as pressure sensitive.
One advantage shrink labels hold over pressure sensitive, say many converters and suppliers, is the ability to provide more information on the label. “With shrink labels you are able to use the entire container as a billboard, whereas with a pressure sensitive label you have to pick a certain area of the container that is not contoured, providing a smaller label space,” says Hill.
Cost is another factor. Anderson of Salem Label says roll-fed shrink labels “provide the most bang for the buck” because the overall cost for OPP roll-fed shrink wrap is lower than the overall cost for pressure sensitive labels.
Lobel says PVC shrink labels are the wave of the future. “Pressure sensitive is the old and PVC is the new,” she says. And the growth of the company says it all. “Last year alone we experienced over 50 percent growth,” she explains.
CMS Gilbreth has also witnessed a rise in the shrink sleeve market, with sales in this area reaching double-digit growth for the company. “A lot has to do with an awakening on the power of shrink sleeves as a packaging choice. To achieve 360° coverage on a product is difficult to do,” says Bruckner.
Anderson provides his opinion. “The growth in this market will become more evident as more and more people realize the advantages this technology can provide,” he says.
Hostetter of AET Films says he has observed the market growing at a rate of 15 percent annually for the last five to seven years.
As the news spreads, the competition grows. Avery Dennison Fasson Roll North America, Painesville, Ohio, has a few of its own products in development, but nothing is commercial as of yet. “We are looking at shrink wrap because we are getting more requests from converters for that type of a product. We may bring something like that to market in the future, but no definite date has been set,” says Stephen Norton, public relations manager. He adds that the company sees strong interest in tamper evident applications.
As for new niche markets, Anderson says he predicts shrink labels moving into the 12-ounce beverage can market as promotional items. “If Pepsi’s Star Wars promotional soda cans were printed on OPP via flexo, it would provide a good solid opportunity,” he says. “Since flexo provides less prepress cost than rotogravure, they can do a greater number of promotions,” he adds.