Flexo for Short Runs

If the print processes offered by today's narrow-web converters were arranged like a multi-course meal, which one would be the main course? Which ones would be relegated to appetizers or desserts? Digital might be jockeying to become the industry's signature printing entrée, but it's clear that in many operations, there is still plenty of room on the table for flexo. At Atlanta-based narrow-web converter GENflex Labeling Solutions, for instance, a print process buffet of sorts is offered, in which both flexo and digital are billed as of vital importance to meeting customer needs.

It's a service arrangement that Kevin Florence, GENflex's president and chief executive officer, expects to continue over the long term—more specifically, with flexo as the meat of the company's print operations, and digital as the potatoes. Though digital has proved highly compelling for short-run, multiple-version packaging applications, recent advances in flexo press technology have made the latter process highly competitive for GENflex's frequent changeover work, with the added benefit of significantly faster throughput. "With our newest [flexo] press easily able to achieve throughput speeds roughly five times that of our newest digital press, and considering the current make-up of our work load, it is hard to imagine that digital output will exceed our flexo output for the foreseeable future," Florence states.

A process history

Flexo's firm modern-day foothold in GENflex's service offering began taking root more than 20 years ago. GENflex, a division of Atlanta's General Paper Goods Company (founded in 1932), began seeing high-growth momentum in the '80s, which prompted a 1991 move to a doubly-sized facility and, shortly thereafter, a steady succession of press technology upgrades. The company, which concentrates its converting operations on pressure-sensitive labels and wrap-around flex-pack applications, first added Mark Andy 8-color and 6-color UV flexo presses in 1995. Five years later, it purchased a Gallus multi-platform UV flexo/rotary screen press to facilitate exploration of additional market avenues. To support continuing growth, a third 6-color Mark Andy press joined the GENflex fleet in 2004.

With an established 10˝ to 13˝ flexo printing capability to serve its customer base—which includes food and food processing, health and beauty, and electrical product companies—GENflex's press investment focus turned to digital technologies in 2007. By 2010, the converter had installed two 13˝ HP Indigo presses. Florence praises digital technology's "eye-popping" 0.5 percent dot output, and its ability to lower GENflex's "minimum order threshold," or minimum standard fixed costs, for high-end graphic applications.

Sorting out short runs

When a short-run job comes in the door, it isn't automatically or exclusively slated for digital production. In some cases, digital technology's parameters simply go beyond the cost and quality scope of a job. "Back in 2007 [when GENflex first implemented digital press technology], people already had a notion that [digital] was too expensive, and we didn't always need all that resolution," Florence relates, adding, "We realized, to our dismay, that digital didn't fit every application."

The availability of both flexo and digital processes, states Florence, allows GENflex to build better and more complete solutions for its customers across either platform. "Once we completed fingerprinting these platforms," he clarifies, "transition between them became transparent to our clients." After output data from both processes was collected and loaded into the company's Esko prepress software for comparison, adjustments were made so that a consistent dot size percentage resulted from each process. "We believe having both platforms affords us flexibility to respond to whatever the circumstance requires," Florence sums up.

Flexo can conceivably be the first choice for printing shorter-run jobs; Florence focuses on total cost rather than total run size to make the best process determination. "In flexo, the footprint of the label can determine the extent of the tooling needed, which may include specific print cylinders as well as the cutting die. This may require consideration as to whether the job is likely to repeat and how often," he explains. Florence also notes that a brand "spot" color can be critical for some customers, and may be better managed on a flexo press than with a CMYK build or custom digital ink.

Taking a servo-driven step

Flexo had, historically, revealed some limitations at the company. GENflex's "struggle" with conventionally geared flexo presses stemmed from the lengthy, station-by-station set-ups, Florence reports. "It could be three to three and a half hours, and four thousand feet of material, before we get to QC signoff," he adds.

In 2012, Florence was hopeful that an investment in flexo's newer servo-driven press technology might resolve set-up frustrations, and deliver higher-end output quality at a throughput level well beyond digital's 100 fpm production speeds. That summer, Florence's hopes were realized when GENflex installed a 17˝, servo-driven Performance Series P7 flexo press from Mark Andy. "Engineered into this press is the ability for quick set-up, quick change-over, and registration control that we have never achieved previously on a conventional asset," Florence enthuses. Additionally, the P7 enables printing of 6- to 8-color work with tight process control, registration, and traps at 500 to 700 fpm—a capability that compellingly dovetails with GENflex's high-volume customer needs. "A food-processing customer might be buying millions of a certain label per month. We must get them in the box and out the door," Florence illustrates.

The scope of process improvements via the P7 brought powerfully clear visibility to flexo's overall place within GENflex's service offering. "We took a look at our legacy business and looked for gains with wider width, more efficient setup, and more efficient throughput," Florence recalls. "We conducted total cost standpoint comparisons with our more conventional press assets and the numbers were pretty staggering." For instance, the company determined that a flexo flex-pack job that had been run for years in a four-across configuration at 300 fpm, could be run on the P7 in a five-across configuration at double the speed, accomplishing a 250 percent improvement in throughput.

Florence makes particular note that the P7 enables improved flexo set-up efficiencies "for the first time." He explains, "We can coarsely register all eight print cylinders to zero in a matter of minutes, get up to color and registration in ten minutes, and pre-set for impression based on material thickness" before moving into fine-tuning. It was this speedy dynamic that paved the way for GENflex's flexo and digital printing operations to work together more strategically. As an example, Florence points to a high-end, 7- to 8-color label application for a family of new household chemical products that was set for a limited test marketing initiative—eight different SKUs with the same graphic look, but varied text, printed at volumes of 1,000 to 2,000 per SKU with seven changeovers.

Digital printing technology was the clear choice for this test marketing run, because once the files were prepped and the jobs were queued, the HP Indigo could switch from one job to the next in seconds while losing just one "frame" (38˝) of material, while flexo, comparatively, would require 25 hours of press setup plus plate costs, Florence calculates. A few years later, with the now-successful product requiring higher label volumes, GENflex realized that the P7's servo registration and turnover efficiency could allow the job to be moved to flex—at cost and time savings that could be passed along to the customer.

Continued processing

The P7's set-up efficiencies "changed our whole thought process" regarding the viability of frequent changeovers for flexo, Florence states. "Setting up jobs successively, one after another, is not as big of a deal from a cost perspective," he reflects. To illustrate, he cites a newer customer's family of protein and supplement products packaged in small plastic tubs with 4- to 8-color wraparound flex-pack labels requiring tight register. "All the products utilize a common container size, so common print cylinders can be used," he points out. "We can be setting up job number two while job number one is on the [P7] press." Previously, the six-SKU, 25,000-foot job took two to three shifts to produce; the P7 can turn it out in four hours.

Next, GENflex plans to harness the P7's web tension management capabilities to facilitate the company's involvement in thin, non-supported film applications typically used in decorative packaging; this initiative will be solidified in the second quarter with the addition of inspecting and seaming equipment. And so, like Sunday's longstanding roast chicken dinner recipe, flexo's functionality appears poised to be reinvented once again. pP