Inside the Digital Paper Labs at Xerox and HP
Scientists compete to make certain their company's papers don't stick, curl, jam, or smear. But even the finest papers can send a print job amok if environmental conditions are ignored.
We take paper sheets for granted, never giving a second thought to the ream of paper we load into the short run digital press, laser printer, or copying machine. But the company that sold the paper is probably obsessed with every scientific detail there is to know.
That, in a nutshell, explains why digital press and related vendors are going to great lengths to develop, manufacture, and sell paper that doesn't foul up inside the machine.
Xerox and Hewlett-Packard are two such vendors going head-to-head in the market for copiers, printers, and digital presses. And they're selling a lot more than just the digital imaging devices.
Every copier, printer, and press they sell opens the door to repeat follow-on sales of paper, inks, and toners. Xerox and HP count on supplying these consumables—preferably all of a customer's consumables—to generate years of revenue that far exceed the initial price tag on a digital press or other output device.
To get the highest printing quality, digital press vendors recommend 'digital paper'; that is, paper that's been engineered specifically to be run through a digital copier, printer, or high-speed on-demand press.
For paper researchers, the devil is in the details. How stiff is the paper? How thick is each sheet? How heavy is it? It's made of wood pulp, but which trees and what chemistry does it have?
"When you get to the engineering level, there is quite a bit that's important," says Joe Kurzweil, manager for Xerox's paper laboratory, in Rochester, N.Y. "There is fiber, filler, adhesives that bind the pieces together, the 'squareness' of the cut, dust, the quality of the wrapper to keep out moisture, caliper, basis weight, and chemistry. And there are the elements that help the toner grip the paper, too. You design the media to reduce the chances of variability."
Xerox tests its digital papers to perform in a variety of normal circumstances, such as an office environment. But it also subjects its papers and hardware to extreme climates, to make certain they function optimally beyond operational norms.
At about 60 degrees at 20% humidity, static electricity can build up, causing sheets to separate incorrectly or even stick together, Kurzweil says. At 80o and 80% humidity, paper swells as it absorbs moisture from the air. Paper curls are the result.
Considering that copiers, printers, and digital presses use heat and pressure to apply images to the paper, "if [paper] fibers are not aligned correctly, you get an imbalance in how they react," Kurzweil says. That can lead to paper handling and output problems, and production delays.
And how paper is handled before it's fed into the press can influence the reliability of a print job. "Before printing, acclimate the paper to the climate it is going to be printed in," he says. "Don't go from the truck to the machine if the truck is at 0o and the shop is at 70 degrees."
When printing an e-mail, few people care if some characters occasionally appear distorted or smudged as a result of using mismatched, low-cost, or improperly handled paper. But for a 150-page small run project, "a single flaw ruins the job," says Kurzweil.
While Xerox's scientists say they know 'everything' about the paper sold under their brand, the company doesn't manufacture a single sheet of it. That job is out sourced to a number of mills who manufacture it to Xerox's specifications, says Stephen Simpson, VP for Xerox's document supplies business unit.
Simpson's unit is keeping the mills busy, selling about 1 million tons of cut paper annually, apportioned among 50 categories and 3,000 SKUs. "We go into an account with as much integration as possible," Simpson says. "We aggressively follow up on the install."
At Hewlett-Packard, paper is not as important as ink-jet cartridges, but "it's a close number two," says Dr. Nils Miller, ink-jet ink and media senior scientist at HP, in San Diego. HP devotes about 50 technical staffers to studying paper at its San Diego lab. "We look at the microscopic level to see what is going on, to continually improve image quality, permanence, and durability," Miller says.
There are 80 characteristics and measurable attributes overall that HP scientists and engineers look at when they examine a sheet of paper. For example, HP tests mechanical properties, looking at friction coefficients measured as paper travels through a printer, and when in contact with other sheets of paper.
"It's really important that paper stays flat, especially in environmental extremes," Miller says. To that end, and like competitor Xerox, HP subjects its papers to torture tests. At 95o and 90% humidity, engineers look for catastrophic failure, he says: "As you get outside the design box, things are more likely to be a bit off."
Both HP and Xerox integrate paper research with other parts of their product design. At Xerox, the paper wizards are literally in the same building as the toner and hardware wizards who are developing new copiers, printers, and on-demand presses. It was precisely this level of close, 'integrated' collaboration that drove development of the company's breakthrough DocuColor iGen3 digital production press.
At HP, while their researchers aren't necessarily physically working in the same room, their paper scientists will collaborate with the ink chemists, and likewise talk to the hardware and software engineers designing HP's printers and presses, to make certain the supply side keeps pace with engineering advancements.
For independent paper companies, such tight collaboration with copier, printer, and press vendors isn't necessarily available (indeed, it's usually not available). And many find opportunities supplying paper to Xerox, HP, and other major vendors.
One good example is Eastern Pulp and Paper Inc., Amherst, Mass. A player in many niche markets, Eastern was eager to get in on the ground floor of the nascent paper market for HP's high-end Indigo digital printers.
Indigo started as an independent Israeli company that wasn't eager to share technical secrets with Eastern, so Eastern's scientists went ahead and figured out how the Indigo digital printer worked. That was the only way they could market a digital paper for it.
"It turned out to be digital imaging with a hybrid offset transfer," says John McMahon, manager of specialty paper at Eastern. The company's engineers came up with their own conclusions on how the Indigo's ink adhered to paper on press, and how images were transferred from the printer's blanket to the paper. That led to Eastern's independent brand.
Rochester Institute of Technology (RIT) does the technical certification of paper for the Indigo press in North America. "We've done extensive work beyond RIT," McMahon says, bringing in outside experts in addition to in-house staff.
Unlike some small- and mid-sized mills that push R&D down to the supplier level, Eastern maintains its own test lab. Large mills, like Georgia Pacific and International Paper, also test their paper on specific digital output devices. And though they won't admit it, some are producing paper that gets branded by familiar copier, printer, and digital press makers, says Jim Forrest, industry analyst and managing editor of the Hard Copy Supplies Journal.
"Paper has good margins," Forrest says. "They can get more money for their brand. Go to an office supply store and you can see branded paper selling for [significantly] more than a generic competitor."
Whether they go it alone or co-develop with mills, Forrest says virtually all the leading digital copier, printer, and press makers regularly send engineers to work closely with preferred mills to ensure products to fit their spec.
They also heavily research competitor's products to make sure they'll work with their printers and presses. "It's the kiss of death if your machine [hardware] only works with [the house brand or] certain papers," Forrest says.
This is especially relevant in corporate and in-plant publishing markets, he says, where buyers won't consider a device unless it works with a wide variety of paper brands. The flip side: on-demand publishers and printers want to keep costs down and supplier options open as well, but the quality of the digital papers they use is paramount.
And that's why scientists at Xerox, HP, Eastern, and other innovative mills will continue their efforts to deliver digital papers that outperform the competition.
- William Terdoslavich