Quality coding for baked products
Continuous-inkjet printer provides high reliability and crisp codes for commercial bakery operation.
Linda Casey, Senior Editor -- Packaging Digest, 10/27/2010 4:21:14 PM
“We probably had conversations for a period of a month and a half to two months,” recalls Knipp. During that time, they identified their customer’s top three initial requirements: The printer had to be suitable for incidental food contact; it had to print codes that would dry quickly to prevent smearing; and the coder needed to work with this specific packing line’s intermittent schedule.
“Quality Bakers may run just a couple of hours a day,” Knipp explains. “They may not package for a couple of days, and then they may run for two or three weeks straight.” After examining several options, Quality Bakers decided to purchase the Hitachi printer because of its auto-purge option.
“Because of its ability on shut down to clean itself, the Hitachi printer allows very easy start up,” Knipp remarks. “You don’t have to worry about removing any excess ink that would be left over because there’s just not any left.”
Keeping its distance
The coder was initially integrated onto the bakery’s hoagie bun and hamburger bun packing line. Buns are manually loaded onto the packing line from cooling racks, where they are conveyed into a LeMatic Inc. bagger. The bagger slices, stacks and places the buns into bags.
Packaged product moves from the bagger to a Burford twist-tie applicator, which closes the bags before they are conveyed under the Hitachi coder. Quality Bakers typically operates the line at speeds between 35 to 40 packages/min.
Of note is the distance between the inkjet coder and the poly-bagged product. Raised bakery products, such as rolls, do not have the benefit of dimensions with very tight consistency. Remarking on the challenges of coding bakery products, Knipp says, “It’s not flat like a corrugated box or clay-coated carton, but you’re always trying to hit the target roughly in the same position, product to product.”
According to Knipp, the Hitachi PB-260U inkjet printer is a good solution for bakeries because “it’s a continuous inkjet printer, and the print head can be mounted a relatively long distance from the product—anywhere from 10 to 30 mm. This allows for rises and lows on the product’s substrate to apply the ink to and still get a readable mark.”
Another challenge bakeries face, Knipp remarks, is the need to immediately handle packaged product after coding. “The products are marked and stacked on top of each other immediately,” he explains, “so there’s a potential for rub off.” The Hitachi PB-260U inkjet printer uses a solvent ink as its standard black. When solvent is used as a carrier fluid for ink, the ink generally dries faster than other types of inks—especially on nonabsorbent surfaces such as plastics.
Explaining why packaging operations shouldn’t shy away from solvent inks for fear of high material costs, Knipp remarks, “Think about the fact that out of a given container of ink, let’s say a liter, you may produce 70, 80 million characters out of that 1 L of ink. I’m sure (coding with solvent-based inks is) one of the most economical means of printing a date code onto a product.”
The No. 3 challenge facing bakery operations, such as Quality Bakers, Knipp explains, is a need to accommodate shorter runs and let the printer either idle or be shut off, overnight, weekends or maybe even several days during a week of non-production. The aforementioned auto-purge option enables bakeries to startup quickly and efficiently after prolonged shut-off periods. Additionally, Knipp notes, the system doesn’t require the nozzles to be handled with kid gloves before being shut down for extended periods. “The nozzle does not need to be covered,” he remarks. “It doesn’t have a secure rubber boot or anything like it because there’s no ink after it’s purged. There’s nothing left to dry; therefore the startup is very clean.”
After two years of production, Cardwell can attest to the printer’s suitability for bakery operations. He says that they originally chose this machine because it printed crisp codes and the price was right. What is his opinion now? “It’s fast, prints clearly and is really reliable,” Cardwell remarks. He adds that Quality Bakers hasn’t found the printer to be expensive or difficult to operate.
Pak-Tec provided Quality Bakers line operators with hands-on training, and one of its technicians is located in nearby Knoxville, which enables fast, 24/7 service. That stated, Knipp can’t recall a situation since the inkjet coder’s installation, when a technician needed to service the printer. He adds that at time of publication, Quality Bakers was just beginning to consider its first preventative maintenance service. “From my perspective for this customer,” Knipp remarks, “the coder has provided a very reliable, very consistent print quality for them for the last two years.”
Ready to take on more
Quality Bakers now codes all of its bakery products, from sandwich buns to specialty baked products for clients both large and small. “We supply Sara Lee, IBC (Interstate Bakeries Corp.) and Aubrey’s Restaurants here in town,” remarks Cardwell.
With its new coding line in place, the bakery is ready to bake and develop new recipes from commercial and private-label customers. “We can make anything,” he remarks. “Just tell us what you want; we can take it from there.”
Hitachi America, Ltd., 704/494-3008, x21.
Pak-Tec Inc., 803/831-2099.
Cana Bag Co., 281/452-6868
LeMatic Inc., 517/787-3301.
Burford Corp., 877/287-3673.