Egg Coding By Citronix Continuous Ink Jet Systems

Egg cartons are not easy to print on, according to Pepe Gonzalez plant manager at the JS West egg plant. "We were using mechanical printers, but we had problems with the dates not being legible,", says Ganzalez. Headquartered in Modesto, CA, JS West is a major egg producer for the CA market. It sells more than 100,000 dozen eggs/dya to more than 20,000 customers.

"We pack eggs in both foam and pulp cartons, and we had problems with both of them," says Gonzalez. "Foam cartons didn't absorb the ink so the ink wouldn't dry and would smear, while the pulp cartons would absorb the ink, but the printing was fuzzy."

Carton coding and marking is a requirement for egg producers. If eggs are packed under USDA's voluntary grading service, the cartong can bear a shield-shaped USDA grademark. According to the USDA, when the USDA grade shield is present on the carton, the carton must also be labelled witht he date and location of where the eggs were packed.

The pack date (the day that the eggs were washed, graded and placed in the carton) is a three-digit code that represents the consecutive day of the year (the "Julian Date") starting with December 31 as 365. When a "sell-by" date appears on a carton bearing the USDA grade shield, the code date may not exceed 45 days from the date of pack. Most state requirements are similar.

JS West prints the production date, line number and plant number on the edges of its cartons.

Smaller industrial printers

"The operators had to keep adjusting the old industrial printers, which reduced the plant efficiency," says Gonzalez. In early 2009, Gonzalesz began to investigate replacing the existing printers.

"We looked at a number of different models and decided to go with the Citronix industrial ink jet printers. The other industrial printers we looked at were bigger and bulky. The Citronix continuous ink jet fit into our existing lines better and they were also less expensive than the other industrial printers we looked at."

The JS West plant has 10 egg coding packaging lines that run one-and-a-half and two-dozen packs and they replaced the industrial ink jet printers on all 10 lines. JS West also purchasedf and 11th Citronix continuous ink jet for an overwrap application at another plant.

Citronix ink jet printers include a user friendly, icon based operating system and video graphic display (VGA) with a full size QWERTY keyboard for effortless operation. Operating settings are automatically adjusted depending on the environment to maintain optimum print quality.

"These continuous ink jet printers are like night and day compared the the industrial printers we had before," says Gonzalez. "For one thing, each one has its own computer, so they're automatic and easy to operate.

The industrial inkjet systems at JS West feature single board electronics technology coupled with integrated smart printhead and ink system components that monitor critical operating functions.

"Most of our line operators have never used computers, but with these the dates are set automatically," says Gonzalez. "The operator just enters the vender or lot number and the computer sets up all of the remaining information."

Housed in rugged, stainless steel NEMA 4-rated enclosures, the Citronix continuous ink jet systems are well suited for operation in JS West's egg packaging operations.

Quick Drying Ink

A big factor at JS West was the use of quick drying inks, which give a dependable and consistent coding and marking on most surfaces and coatings. They have fast evaporation and high solids content, so they offer excellent dot definition and readability. "The quick drying inks don't smear on the foam cartons and they also work well on the pulp egg cartons," says Gonzalez.

"Citronix was very helpful," he continues. "They were here every day during the several weeks that we were looking at the system and they helped us install and start up the industrial printers. They've been someone we could rely on and we are very comfortable calling them when we have any questions or need assistance with our continuous ink jet printers."