Demand for radiation-cured products continues to grow as printers, ink manufacturers and suppliers become more familiar with the technologies and separate the facts from the rumors. When you hear the term radiation-cured ink, you might immediately assume it is referring to ultraviolet (UV) inks. But there is another type of radiation-cured technology beginning to make inroads in the printing ink industry – electron beam (EB).
EB inks might not compare to UV inks in terms of market share or end use applications, but the technology holds promise for future developments.
“The number of energy-cured products that we come across on a daily basis continues to grow and as more converters move into this market, we think that the claims made about the cost effectiveness of this technology are being proven,” said Michael McGovern, director of sales and marketing, energy curable and sheetfed products, Sun Chemical Corporation.
Inks are not the only EB products available from ink manufacturers. Demand for EB coatings and adhesives is also on the rise.
“EB inks comprise a small specialized area in the marketplace,” said Fred Zinnbauer, business development manager, Akzo Nobel Inks. “Generally speaking, EB curing is most often used by suppliers providing adhesives and release coatings to the converting industry.”
“EB coatings and EB adhesives are the areas that appear to offer the greatest potential growth segments in the energy cure arena,” said Mr. McGovern.
The greatest obstacle deterring printers from becoming involved with EB technology is the price of EB curing equipment.
“I do not see EB being different from a chemistry standpoint,” said Guy Harris, technical director, Nor-Cote. “The major issue is on the equipment side with cost.”
“The biggest barrier to switching is the up-front hardware cost of the EB cure units,” said Dr. Don Duncan, director of research, Wikoff Color Corporation. “Also, newer sheetfed litho presses run much faster than they did a few years ago and pose an increasingly attractive alternative in terms of high throughput. However, if a printer wants to get into businesses that play to the strengths of EB inks, such as food packaging and chemical resistant products, the ante to play is EB hardware.”
The higher prices of EB inks may also be limiting growth of the technology.
“There is a substantial investment in electron beam equipment, and the per-pound price of the ink is slightly higher than conventional inks,” said Dr. Paul Gupta, technical manager, radiation cured inks, Flint Ink Corporation. “However, we believe there are a number of advantages that help balance the added cost.”
In the Grocery Store
Many of the recent advancements made with EB technology have been in the food packaging segment.
“A major opportunity awaits in the food packaging market where migration, taint and odor are significant concerns,” said Mr. Zinnbauer.
“The vast majority of EB inks are used in food packaging,” said Dr. Duncan. “This is because the very high degree of ink cure obtained with EB technology gives very low levels of residual extractable or volatile material from printed cartons. This is important to food packagers.”
SunBeam LE, a new EB curable coating that is FDA compliant for direct food contact, is ideal for use in applications such as flexible film, paper packaging, multi-wall sacks and food cartons where an inside coating is desired, according to Sun Chemical. In addition to offering FDA compliance, the company said SunBeam LE coatings provide high gloss, chemical, heat and abrasion resistance.
“SunBeam LE is revolutionary. It is a significant technology advance in the graphic arts industry,” said Christopher M. Morrissey, vice president of sales and marketing. “More than 30 years ago, Sun Chemical developed, patented and introduced technology for UV light-reactive inks and coatings. In the mid ’70s, we released our SunBeam line of EB inks and coatings that were well suited for food packaging where direct food contact was not required.
“With SunBeam LE for direct contact, Sun takes another giant step forward,” added Mr. Morrissey.
According to Sun Chemical, SunBeam LE coatings can be used in direct contact applications under all conditions of use and in contact with all food types in full compliance with the federal Food, Drug and Cosmetic Act with all applicable food additive regulations provided the coatings are properly applied, cured and do not exceed an applied film thickness of eight microns.
“This is the first electron beam cured coating that is compliant to FDA regulations concerning direct food contact,” said Mr. McGovern. “We feel that this technology will open several new markets as well as go a long way to ease concerns with the use of energy cure products for food packaging.
“Sun Chemical has converted all of our EB ink users to our Sunbeam 2000 resin technology, which has resulted in better printing inks that are stronger than our previous resin system would allow, that run faster and cleaner and provide our customers with productivity gains that make this system more economical than previous technology,” added Mr. McGovern.
Ink manufacturers continue to focus R&D efforts on key areas related to EB technology such as education and safety.
“Concerns about EB technology that normally have to be addressed when dealing with new or potential customers revolve around safety issues both from a hardware standpoint (the beam) and an ink/coating concern,” said Mr. McGovern.
“All energy-curable products, both UV and EB, are skin irritants,” explained Dr. Duncan. “This is easily handled with simple safety equipment, but pressmen making the switch from oil-based litho or water-based flexo to UV/EB need some safety training.”
But Dr. Duncan said the risk of skin irritation when using EB products has decreased “as chemical suppliers have improved many of the raw materials used in EB inks.”
Shelf life is another area of concern for manufacturers of EB products. “Six months is typical, assuming the inks are stored properly, but storage conditions, especially temperature control and non-UV lighting, are critical,” added Dr. Duncan.
One way to introduce printers to the benefits of EB technology might be with UV/EB combination presses.
“The use of combination presses using both UV and EB curing is on the upswing,” said Mr. McGovern. “This seems to be a rather recent development and we will have to wait and see how this new technology fares in the marketplace.”
“If the new, very small EB units, such as those being pushed by a couple of start-up companies, are successful, then perhaps combo press use will grow,” said Dr. Duncan. “These new units allow the use of UV curable inks and EB laminating adhesives, or other combinations. For the most part, however, the relatively large investment for a standard EB cure unit that has the power to cure ink, coatings and adhesives in one pass ensures that those that buy the beamer will use the beamer.”
Mr. Harris said combination presses could offer advantages to screen printers. “There is the potential within the rotary screen segment for a printer to have a UV unit for the first few layers, and then put an EB unit at the end,” explained Mr. Harris. “This could have interesting advantages.”
A Bright Future
Printers know what they need from EB inks in order to feel they are a viable option, both now and in the future.
“Printers using EB inks are continually pushing for inks that provide them with better printing characteristics (stronger, sharper printing), better process handleability (wider water window, less misting), that will print and process at ever increasing speeds, and that will run on a wider range of substrates,” said Mr. McGovern.
Recognizing the potential that EB technology holds, Wikoff Color Corporation recently announced a 40 percent expansion of its energy curable bulk manufacturing plant in Fort Mill, SC.
Although Nor-Cote does not currently manufacture EB products, that could change if interest in EB technology grows. “If our customers start to look for EB products because they need low odor or high opacity inks, then we will follow,” said Mr. Harris.
“It appears that converters using energy cure technology are showing a preference for EB over UV when looking at new equipment,” said Mr. McGovern. “The emphasis on productivity, quality and cost have impacted the EB web markets in the same way that the conventional markets have been impacted. Converters want to run higher quality products at ever increasing speeds for less cost.”
Consistency might be one area where EB inks could surpass UV inks. “Consistency is achievable due to the fact that the controls on the EB equipment automatically maintain a consistent dosage of energy regardless of speed changes,” said Dr. Gupta. “On the whole, it is harder to obtain such consistency using UV processes.”