SPECIAL REPORT VARIABLE DATA PRINTING -- Digital Print Goes Postal

Automation has been a central theme of efforts to keep the U.S. Postal Service (USPS) viable and to make it more competitive. The printing industry has a vested interest in the success of such efforts, but also must contend with some negative consequences.

According to a PIA/GATF estimate from Ronnie H. Davis, Ph.D, chief economist, about 45 percent of the dollar volume of printing in the United States ends up being mailed. That figure represents materials entering the mail stream directly from the printer and indirectly via a mail house or the print buyer.

In dollar terms, this amounts to some $70 billion in annual printing shipments passing through the USPS, Davis says.

Unfortunately, automated handling can put added stress on printed matter. John Lind, PIA/GATF senior research scientist, points out that First Class mail typically is subject to automatic sorting by several machines, including the Advanced Facing and Cancellation System (AFCS). This machine employs many wheels and belts to enable processing of up to 39,000 envelopes/ postcards per hour.

Design Behind Bars

It also applies a fluorescent orange barcode on every piece to facilitate subsequent handling. While not "damage" per se, the barcode also can detract from the appearance of a beautifully designed and printed self-mailer piece. This is particularly true if the barcode falls in a white or light colored area.

Digitally printed material may face a disproportionate risk because a larger percentage of this work—especially variable data printing—is mailed and the finished product is believed to be less durable. PIA/GATF set out to test that latter assumption by mailing sets of samples from four cities (New York, Chicago, Miami and Los Angeles) to the association's headquarters in Sewickley, PA.

The samples produced were all variations of the same piece—a 6x9˝ postcard promoting the 2005 TechAlert Conference—printed from the same file. The postcard's design featured extensive toner/ink coverage on the face, with the back dominated by a large white area for the mailing panel.

Sets of 25 postcards were printed on both digital (toner) and digital offset/direct imaging presses for comparison, as well as with and without various protective coatings, including aqueous and UV options. The lineup of system vendors who agreed to participate in the test included Heidelberg (Quickmaster DI Pro), Hewlett-Packard (HP Indigo 5000), KBA (74 Karat), Eastman Kodak (KPG Direct Press 5634DI and Kodak NexPress 2100), Xeikon (DCP5000) and Xerox (iGen3).

All told, nearly 3,500 postcards were mailed. Each postcard was hand sorted and analyzed by PIA/GATF scientists as it was received. "Some postcards arrived without a mark on them, while others were delivered in pieces inside an envelope," Lind reports.

According to the scientists' analysis, UV coating offers the greatest protection and is aesthetically pleasing, but was deemed less "postal system friendly" because it didn't accept ink-jet printing. Applying an aqueous coating was found to be a good solution for protection of digital and digital offset/direct imaging printing. As a rule, digital offset prints arrived mark-free.

Even with the care taken to ensure the postcard's format met the guidelines for First Class letter mailing and automatic sorting by AFCS, the researchers found significant variation in how the USPS processed samples. Whether or not a protective coating was applied accounted for some of this variability, but geography, surprisingly, was also a factor.

Table Tells the Tale

The accompanying table shows a breakdown of the findings by coating.

According to Lind, there were indications that adding a coating has potential to create issues with AFCS processing. The various coatings limited the penetration and adherence of the ink used to apply the fluorescent barcode, leading to smearing, he explains.

To address this concern, postal operations may first run a piece through the Label Making Letter Machine (LMLM), points out the PIA/GATF researcher. That machine applies a pressure-sensitive label with an ink-receptive white face to accept the barcode. The labels are bad enough, but Lind says processing via LMLM also further increases the risk of a piece being marred as it's passed along by more belts, wheels, etc.

Ironically, the best explanation for the variation in use of automated processing methods seems to be the human factor.

"It was curious that almost 30 percent of all postcards mailed from New York City and 37 percent from Miami carried the LMLM labels. The Los Angeles and Chicago sites used LMLM labels on less than 3 percent of the same postcard variations. The reason for this difference isn't clear, but it may be due to floor-level management decisions on how to treat the postcard most efficiently," Lind says.

As a final thought, he notes that an important element of the experiment was getting all of the participating companies to print on the same substrate. Mohawk Paper agreed to supply two grades (7-pt. and 9-pt.) of its Navajo stock and, in turn, asked SMART Papers to provide two grades (8-pt. and 10-pt.) of Kromekote for the mailing experiment. This enabled the researchers to separate effects of paper caliper from effects of printing technology.

A complete report is available from PIA/GATF Press at www.gain.net.

—Mark Smith