Foil Stamping Technology

July 11, 2005

An increase in foil decoration among packagers is propelling this converting process forward.

Foil Stamping Technology

ecoration is the operative word today. The innovative packaging customer is pressuring the converters and their suppliers to bring new ideas to the table, to make the product sing from the shelf. For this reason, the industry is witnessing a resurgence of foil stamping in certain markets. One area in particular, the one that seems to have the attention of every converter, is the wine market. For the wineries, foil can make the difference in that blinding instant of decision that descends upon the consumer every day.

Foil stamping has traditionally been known as hot stamping, because of the heat and pressure combination that weds the foil to the substrate. Hot foil stamping is accomplished in one of two ways: the rotary method, in which the foil is applied in-line; or through the use of an off-line hot stamping press. Each process has its advantages and disadvantages.

Relatively new to the marketplace is the process known as cold foil. This involves the transfer of foil to substrate in-line using adhesive, foil and pressure in a standard print station, rather than employing a rotary hot stamping station. The process has been used by individual converters over the years — those who have developed the process on their own — but is becoming more widespread.

As little as a year or two ago, conventional rotary foil stamping was a slow process. According to John Gallagher, vice president of Total Register Inc., Brookfield, Conn., quite a bit has changed since then. “Speed for rotary foil stamping has tripled in the past two years, because of major improvements in foil chemistry. Still, there is a lot of room for growth, for more speed,” he says. “Foil technology, to me, is now comparable to the flexo market.” Total Register manufactures rotary stamping systems, both for converters to add to their existing presses and as an OEM for press manufacturers.

“I suspect that in a year’s time,” he adds, “there will be no speed issue with rotary hot stamping and flexography.”

Rotary foil stamping can be an expensive proposition, because the foil is costly. The customer knows it, and pays for it if he or she wants the added decoration. But one of the big issues in rotary foil stamping has always been the waste factor. When the foil is driven by the press, it travels through the stamping unit at the same rate of speed that the web travels. The foil is stamped into place and the foil roll turns until the next stamp is ready to be imprinted. Between those two impressions is, quite frequently, a vast expanse of unused foil that the customer is paying for.

Total Register is awaiting approval of a U.S. patent for a device it calls Foilsaver, a shuttle-controlled system that regulates the speed of the foil through the rotary stamping unit, and which causes the foil roll to pause and back up so that the next impression is adjacent to the first. The result is a stamped roll of foil filled with impressions, and utilizing a fraction of the expensive foil.

The system operates through the use of a magnetic sensor, which senses a magnet embedded into the stamping die, and which then sets the position of the die. The system now allows for variable repeats. The first Foilsaver was put into the field in December of 1997.

“One winery that uses our Foilsaver system was able to buy half the amount of foil it used to buy using the conventional rotary stamping,” Gallagher says. The company now has its equipment in the United States, England, the Netherlands, Russia, China and Australia. Total Register also provides OEM equipment for Aquaflex and Webtron, Propheteer and Nilpeter presses.

Off-line presses
Several companies manufacture and distribute stand-alone hot stamp presses. Those include Franklin (owned by Foilmark), Newfoil, Rapid Machinery and Shiki. The off-line stamping presses are more often than not used for medium to short runs.

“We’ve been selling to a lot of new customers,” says Patrick Walker, national sales manager for Newfoil USA, North Attleboro, Mass. “We’ve come out with a new version of our press that allows for direct integration of a thermal transfer printer, and allows for lamination and diecutting.”

Walker also sees the surge of foil decoration in wine country. “The market is growing in the wine pressure sensitive business, and we are seeing a lot of machines going to the wine label makers on the West Coast,” he says. “They are probably growing faster than any other segment now.”

Hot stamping on the off-line machines, Walker notes, used to peak at a speed of 6,500 impressions an hour. “Today we’re up to 9,000 impressions an hour, depending on how much foil you’re putting down.” Rapid Machinery says its units will go as high as 14,000 per hour.

Though the speeds are slower, the off-line hot stamping press uses only as much foil as is necessary. The foil is pulled across the web in increments, with little waste. Press set-up is typically 10 to 15 minutes.

As for cost, “it depends on the volume,” says Walker. “A large number of label manufacturers who have installed rotary hot stamping units have come back to us because of the economics of setting up the job. If the volume isn’t there, the economics aren’t either. Some have given up on rotary because they couldn’t accommodate their smaller customers."

Growth in security
Hot stamping is for more than decoration. Holograms are now being stamped in register on a multitude of products, both for security and for decoration. “Others in the security market are working with RF (radio frequency) type security labels,” Walker says. The converters stamp receptive materials onto a label and charge them with magnetic tape. They then operate at different frequencies and can be identified in consumer retail operations. “It’s a huge market,” he adds. “There’s so much you can do with our type of machine in that industry. RF is the sort of material you can’t waste a lot of. You have to be able to set up quickly and have reliable print-to-cut registration every time.”

The cold treatment
“Anybody can do cold foil,” says John Little, president of Nilpeter USA. “What we did in our cold foil package is to maximize the opportunity to do it right.

Nilpeter is among the few who have successfully experimented with cold foil, which involves the pattern application of a special adhesive via a photopolymer plate onto the substrate, and from there applying the foil under the pressure of a roll and UV curing the adhesive. One converter who developed his own process some years ago is Driscoll Label Co. of Fairfield, N.J., which has trademarked its product as StarBrite. Several other converters have licensed the product from Driscoll.

“It’s a combination of plate, adhesive and foil characteristics,” says John Gallagher. It may come to pass that cold foil is a strong adversary to hot stamping, but Gallagher says that one strong disadvantage is in “the edge effect,” or what happens to very fine edges of foil in the cold transfer process. “The edge effect is much more of an issue with cold foil,” he says.