Make a Good Impression

Stamping and embossing experts reveal how to get the best results from the package-enhancing processes.

by Kate Sharon, Associate Editor

THE VALUE OF stamping and embossing equipment is well known. In today's retail world, where it's hard to walk down a grocery store aisle without seeing several packages enhanced by the glimmer of foil, stamping and embossing capabilities are a converter's key to value-added products.

"Increasingly competitive markets create a larger demand for differentiation in product, packaging, and promotion, which is perfect for foil stamping and embossing," according to Jim Hutchison, senior vice president of sales of Universal Engraving Inc., a foil stamping and embossing die manufacturer. "… Foil stamping and embossing can be utilized alone or as a compliment to printing and/or diecutting. Foil stamping and embossing grabs the customer's attention through visual and tactile senses. By adding the process, it automatically provides a perceived higher value [for the package]."

But, as per usual in the package-printing industry, owning and running the equipment isn't enough. Converters need to know and understand the machinery inside and out, including foils and dies, to make the most of their investment.

packagePRINTING talked to industry insiders to get their advice on what converters need to know to produce superior stamping and embossing results.

From the beginning

Makeready is a critical step in the converting process where companies can save time and money. It takes operator know-how to get the machine set correctly, but being prepared with the proper makeready tools, or support materials, helps make setting up the stamping die easier and less time consuming, said Sam McElree, product manger of KURZ Transfer Products, a foil manufacturer.

"When you come from the stamping industry, the most important element is the time you spend on the makeready," McElree said. "The time you spend shows up in your finished product. For example: Spend more time on your makeready in the beginning and less downtime every 500 sheets repairing makeready."

In addition, once makeready is complete, it's necessary to have quality equipment to ensure accurate control and advance of the foil. "[This] ensures optimum usage and minimum waste," said Chris Raney, VP, folding cartons, Bobst Group USA Inc.

Heating basics

Heat is no small factor in the stamping and embossing processes. Speaking specifically of sheetfed stamping, the ability to maintain consistent heat and alter heat within zones on the run is essential, Hutchison said. "This is critical in job efficiency—getting the job made ready and keeping the job performing at the same levels throughout the run," he said. "Heat greatly affects the way the sheet reacts to the foil stamping and embossing, as well as to the foil itself."

Uneven heating in any kind of foil stamping and embossing often results in "dirty" foiling, and potentially a rejected job. "The heat requirements of the foil need to be controlled to ensure accurate and clean foil release without excessive heat," Raney said.

One way to ensure that the heat is even across all zones is by using a surface pyrometer, recommends McElree. A surface pyrometer determines the actual temperature on the surface of the stamping die and compares it with the temperature readings on the machine dials. "It lets you double check the gauges, because they can be off by as much as 10-15°F," McElree said.

Keep the pressure on

Appropriate pressure is an essential ingredient in stamping and embossing. With sheetfed stamping, consistency and even application are key. "The pressure is necessary to apply foil and emboss, and when it is uneven you have to spend a great deal of time trying to build up the pressure in specific areas," Hutchison said. "The image area of the embossing or foiling determines the amount of tonnage required. If the machine doesn't have the necessary tonnage required, the image won't stamp clean or you won't get enough out of the embossing die or you'll possibly smash the die in attempting to maximize the tonnage," he said.

This is where a converter needs to understand his or her stamping and embossing equipment, including its capabilities and limitations, Hutchison said.

To begin, the very layout of the job needs to be balanced to make certain that pressure is evenly spread across the stamping and embossing surface. According to Raney, this not only ensures a quality result, but also protects the mechanical integrity of the machine—an important point, considering the cost of downtime due to equipment repairs or a ruined die.

In addition to a balanced layout, converters using rotary stamping equipment can protect themselves against damaged equipment and dies with a little tweaking of the system, said I.KELA General Manager Peter Kuschnitzky. "When hot stamping, do not use too much pressure—instead increase temperature, slow down the press, or change the foil," Kuschnitzky suggests.

If the pressure is balanced and a converter still has problems achieving clean foiling, the problem may lie within the image design itself, McElree said. "You need to work with the designers. You can't have a heavy solid image next to fine copy or lines, because the heavy area will bleed over to the fine copy," he said. "Most designers don't think about that unless you tell them. The designer has to be a part of the process."

Engraving matters

Stamping and embossing die engravers can offer much more than a finished die. According to Hutchison, "It is important to always consult with your engraver in the prepress planning stages to ensure that all critical areas are being addressed and that you get the proper die or cylinder for your applications. This helps to avoid unnecessary delays and costs associated with trying to fix the problem after the die is on press. It also helps to ensure that the finished job meets the expectations of the customer and designer. Your engraver can often provide suggestions to improve the job with the die and some engravers also offer makeready technical assistance."

In addition, recent improvements in engraving technology have led to a new process of engraving called CNC engraving. This new manufacturing method is sometimes an alternative to more conventional methods of chemical etching and hand engraving. This new process is one of computer operation and the software systems can create exact duplicate dies in less time.

"One of the biggest improvements is that engraving software and equipment has become—for lack of a better word—more artsy," Kuschnitzky said. "It's getting closer to the software that prepress people use when making printing plates—closer to what the graphics industry is using. It's able to do almost anything an artist can come up with. It's also faster than it used to be."

I.KELA recently purchased new engraving equipment that's five times faster than earlier machinery. "Software improvements have helped increase the detail achievable and, therefore, improve the registration when manufacturing tooling," Kuschnitzky said.

Resources

American Die Technology www.amdie.com

Bobst Group USA www.bobstgroup.com

Brandtjen & Kluge www.kluge.biz

I.KELA www.ikela.com

Inta-Roto www.inta-roto.com

KURZ Transfer Products www.kurz.de

Precision Hot Stamp www.precisionhs.com

RotaCom US www.rotacom.ca

Schober USA www.schoberusa.com

Universal Engraving www.universalengraving.com