What's All the Buzz?

Energy curable. It's the latest buzz and time has proven that UV and EB curing of coatings and adhesives can save printers time and money. And that's a goal that is as sweet as honey.

PICTURE IT: COMPANY XYZ calls you for 10 rolls of your finest flexible packaging. Oh, and can you add a laminate to that, too? Oh, and one more thing … we need it by Thursday. So what do you do? You complete the order as quickly as possible and then start the hunt for a technology that can solve this problem on a permanent basis. This is where ultraviolet (UV) and electron beam (EB) curable coatings and adhesives can come into play.

Currently, many converters use the ol' "let's glue these layers together and then let them sit in the warehouse for hours and even days until they are completely dried" way of curing. A good practice if one is leavening bread. Not a good practice if one is competing with many other printers for the same job. packagePRINTING asked some manufacturers of UV and EB products what they have to offer customers.

So really, what is it?

Knowing if UV or EB is the way to go, starts with knowing exactly what they are. There are some similarities, but many differences as well.

According to Rick Sanders, sales and marketing, Energy Sciences Inc., EB is prevalent in the conversion of food packaging, and it involves accelerated electrons passing through a foil window that penetrates the product or materials. The electrons cause the desired and almost instantaneous changes in the EB curing material. These changes typically result in better visual properties than water-based materials, and can provide enhanced shelf appeal, he says.

One similarity between EB and UV is their highly sought-after ability to cure instantly. While EB uses a beam of electrons to accomplish this, UV employs a specific wavelength of light from a lamp that causes a reaction with a component (photoinitiator) in the material. UV coatings are usually clear, but some opaque offerings are starting to hit the market. Jim McCusker, president of Honle UV, said. "UV is an extremely established technology and fundamental in the label industry."

So what are the perks?

It's difficult to speak about any technology without talking about that not-so-taboo subject, "Hey, what's this going to cost me?" It's a good question—a simple one that may bring out more of the similarities in the two technologies. Yes, both have an opportunity to save the printer money, but one has to know where to look to actually see the savings.

"In the past, an EB machine may have cost $1 million and it was the size of a dump truck," said Sanders. "Recently technological advances have lowered the price to $500,000 and to the size of that of a refrigerator laying on its side. These are huge advancements."

So the price is cut by half, which is good in the big picture, but where can more savings be realized? "In the final product," says Sanders.

Part of the "pros" of EB is having the ability to skip a complete step in the converting process. By using an EB clear top coating, the lamination of a layer of film can be eliminated in various applications. "EB becomes cost effective when 'skipping' the process of gluing two layers of film together," Sanders said. "There is a 10 percent savings in the raw material costs because of leaving out the adhesive step."

Another area where savings is obtained is in the immediate curing of the coating or adhesive. "The time it takes solvent-based materials to cure can take anywhere from 12 hours to four or five days. Instead of the materials sitting around the shop waiting to be cured, EB materials can be cured on-line," said Sanders.

UV also saves printers time and money, in much the same way. "The benefits of UV include the ability of instant curing and at high speeds of operations," said McCusker. When compared to solvent- and/or water-based inks and materials, the list of pluses for using UV materials is relatively long. According to McCusker, the lack of solvents makes UV environmentally safe, because nothing has to be "flashed off," or discharged into the atmosphere.

McCusker also says that almost all press technologies can incorporate UV capability into their lines. Benefits can include higher quality products because of the high gloss and high abrasion resistance that UV systems have to offer.

Challenged to a dual

So both technologies are starting to sound pretty good: cost efficient, time savers, and Earth friendly. But that's when they're compared to other coating and adhesive systems. What about when they are compared to each other?

"EB must be a well-liked technology, because a lot of folks use it, especially in frozen food packaging, ice cream packaging, and cereal packaging," offered Sanders.

When compared only to UV and no other technology, EB can be considered easier on the wallet because there is no need for photoinitiators, which are very expensive. Sanders said the photoinitiators may also leach out into food products, rendering it unacceptable for food packaging. But, he did offer a drawback to the EB systems—nitrogen has to be available inside the curing zone of the machine.

McCusker believes that UV is a better investment from an equipment standpoint than EB because the on-going cost of the UV lamp replacement is much lower than the investment a converter would have to make into an EB system. McCusker says, "It's easier to replace a lamp than a beam. When a beam goes down, I've heard it can take a long period of time to get the line moving again."

By Megan Wolf

Assistant Editor