A Case Study in Ink Testing and Vendor Selection

By: W. Eric Schult

Here at The Fayetteville (N.C.) Observer, we are conducting an experiment during a shift usually reserved for press maintenance. Two veteran press operators are emptying the color ink fountains on the odd side of towers two and six and will clean them out thoroughly before replenishing each fountain with exactly 5 pounds of ink. In one tower, the inks we’ll return to their respective fountains are the very same cyan, magenta and yellow that we just removed—a standard, NAA-certified ad-litho product that we’ve been running on our press for the last four years or so. In the other tower, we’ll be introducing a grade of process colors purported to contain substantially stronger pigments.

In theory, the high-strength inks will let us back off both water and ink to achieve the same reproduction qualities we were getting with the standard inks. There are advantages to that. Delivering a drier sheet to the folder and conveyor cuts down on ink being tracked down the page, or offset to a facing page when it comes into contact with nips and trolleys and squeeze rollers along the way. A less saturated page will also have less of a tendency to transfer ink to our readers’ fingers while they’re trying to juggle their paper and their favorite Starbucks pastry.

There could be other benefits that are invisible to our customers, but no less compelling to me for selfish reasons. Backing off on ink and water levels should cut down on the slinging and misting of ink droplets off the roller train of our high-speed press towers. That would save hours and hours of housekeeping labor in the pressroom and let us refocus our finite resources on preventive maintenance tasks that might otherwise go untended.

The bottom line is this: The high-strength inks are way more expensive than the standard inks. We need to understand the extent to which that added cost per pound might be offset by a proportionally better yield. Our test is intended to measure the relative mileage we can expect to get from both grades of inks so we can take that into account when we make the broader business case for one or the other.

Our conclusions might not square with those of another printer or publisher, but the journey in choosing between ink grades and vendors may be useful for others balancing their options.

As I write, I honestly do not yet know the outcome. I’m confident though in the methodology. We’re running the exact same print job—a two-page jacket on 55# stock— off two ends of the press at the same time—half of the total run quantity we need off each side. We’ll be matching the press speeds, measuring ink densities with the same densitometer, and employing two towers that have recently undergone roller replacements and had their roller settings optimally tuned. Having removed as many of the variables as possible, we’ll run through the 5 pounds of ink in each fountain until the first process color is depleted. We’ll clean out and weigh any residual ink in that fountain and capture the data for how many gross impressions we produced with the calculated pounds of ink that were consumed. We’ll refill that fountain and continue the press run, stopping to capture yield results as each fountain runs dry. The entire cost of the test is in a few thousand extra waste copies of the jacket that will be generated during the stops and re-starts, plus three, 45 pound pails of high-strength ink.

The technical sales representative for the vendor of the high-strength inks acknowledged during the week preceding the test, “Your test case scenario is about as good as any you’re going to get in the same press room.” He’d pitched us on a broader test to supply color ink for a month or a quarter to compare total consumption and cost over the same timeframe using standard inks.

He’d produced written testimonials from newspaper customers who’d tried this, experiencing net savings as a result of upgrading. However, that approach didn’t appeal much to me; it seemed too anecdotal. With so much variation in workload from week-to-week, month-to-month and quarter-to-quarter, who’s to say the results didn’t have more to do with fewer total impressions of color pages during the test period? One heavy-handed pressman on vacation could have as much to do with the difference.  

Truth-be-told, we already had our own anecdotal evidence of ink yield variation. Earlier this summer, we’d purchased a tote (about 3,000 pounds) each of high-strength CMY for targeted use on a new class (to us) of commercial print customer. We knew from experience we wouldn’t be able to avoid tracking and offsetting on the stocks they were using (a 92-brite offset, for one), unless we dialed down the ink and water and wiped down every belt, roller and trolley that touched the sheet.

It worked!

We surprised ourselves—and the customer—with the product we were able to produce and I say that with an immodestly high opinion of our usual reproduction values. We proved we could notch up our capabilities with the high-strength ink if we combined it with some over-the-top prep work. We noted with interest that we eventually got two solid weeks of use out of the high-strength totes, compared to seven to 10 days with the standard ad-litho totes, but couldn’t rule out other variables affecting that yield, so we limited our conclusions accordingly.

All of this is tempered by an acknowledgement that we can do a better job with ink/water balance to make standard ad-litho ink run better on our press, improving mileage and ink densities without investing in high-strength inks. We passed our SNAP re-certification this summer, utilizing standard ad-litho inks and ink/water curves not optimally tuned for our press.

We also had apparently been operating at a disadvantage for at least a short time preceding our SNAP test, owing to a tote of cyan ink that tested 12 percent below ad-litho specifications (according to lab results conducted by our current ink vendor’s competitor). That condition would necessarily have forced us to apply more ink and water to get the pigment on the page and achieve SNAP density. It also would help explain, if our current cyan is consistently weak, why our blue ink tends to scum way quicker than the other colors.

One good piece of advice we picked up during this endeavor is to regularly ask your ink vendor for its technical assistance in tuning your press to its inks. Any substantial change you make in your pressroom—a new paper, grade of ink, fountain solution, roller change, etc.— can have unintended consequences in how their product performs.

“It’s nice to have us out here,” our technical rep said. “We don’t call it ‘fingerprinting.’ We call it a snapshot.”

According to my pressroom manager, the snapshot our vendor provided in August “proved we’re running too much ink and emulsifying it.”

We’re still working on that balance. As one vendor pointed out, “Over-emulsification causes everything to go haywire. The trick is to control your emulsion.”

An added challenge for us is that we’re about halfway through a two-year capital upgrade of all the ink train rollers on the press. Finding an ink/water curve that works optimally on towers that have already been refitted with new rubber is one thing; finding one that will also work on towers with older, time-hardened rollers is something else.

Our vendor accomplished some good work, introducing an ink/water curve that was optimal for at least the one tower on which it was tested.

“Startup should be easier and quicker. Quality should come quicker and you ought to be able to hold it better without chasing it,” our rep said.

However, there were subsequent complications with applying that curve across the whole press, so we’ve still got work to do. As he’d warned us: “The wheels are lined up now, but they’re not necessarily balanced.”

While that work continues and before the drum roll crescendo on those ink yield tests, it’s not straying far from the subject to reflect on ink optimization software and the impact that that can have ink consumption and total cost.

Ink optimization is a technology by which the gray elements in color photos and graphics—normally achieved by mixing equal parts of cyan, magenta and yellow—are modified to use more black ink and less of the more expensive process colors. It’s a technique that’s been around for decades, but attention to it in newspaper circles seems to go in cycles.

This was a hot button topic for awhile five or six years ago, according to the prepress specialist in my IT department, and he’s seen recent interest in it re-emerge with new approaches that purport to squeeze out more savings and improve the reproduction quality of page elements manipulated in this way.

You’re probably already using ink optimization, if in no other way than while applying levels of UCR/GCR (under color removal/gray component removal) in Photoshop when toning photos. When it’s handled this way, it’s only getting applied to individual photos—not all the color elements on a page—so vendors of preflight software and prepress workflow solutions got into the game with plug-ins and stand-alone products to capitalize on the potential for broader use and bigger savings.

“Some will claim they can save you 25 to 50 percent, but that’s based on people that are doing nothing (with optimization). That’s a best-case scenario,” my prepress specialist said.

For us—between the Photoshop toning we are already doing and the use of an ICC (international color consortium) profile that defines our total ink limit, maximum black and dot gain—the potential for savings is more limited. Using Inksave, a plug-in for OneVision’s preflight solution called Asura, we’ve experienced savings as high as 10 to 12 percent using aggressive levels of optimization, but recently scaled back to avoid degradation we were seeing in our reproduction values. We currently achieve 4 to 5 percent savings using the level of optimization upon which we settled. A decision to boost the pigment strength in our inks or an adjustment to our ink/water curves that delivers a stronger black density with less ink consumed might cause us to revisit our optimization settings.

As it turns out, our yield test today illuminated a substantial difference in mileage between the two grades of ink—enough by itself to justify a 53 percent premium price on the high-pigment product (see table). Since the unit price from both vendors is proprietary, I’ll only say it will be incumbent upon me to provide additional justification for any wholesale switch I might propose. I won’t rule that out, just yet. I’m certain I can project a windfall in reduced maintenance labor based on a corresponding reduction in misting and fling, even if quantifying that will be a challenge. Some reduction in startup waste isn’t hard to imagine either since the press operators found the product more forgiving than the standard ink. What potential for new revenue is there in the use of a higher-grade ink? Is there enough of an obvious difference in quality to add that argument into the equation? These are the questions we’ll be ruminating upon in the name of due diligence.

W. Eric Schult is the operations director at The Fayetteville (N.C.) Observer. Contact him on LinkedIn.com or at schulte@fayobserver.com.