Job Design
FLEXO: On Flexo Tech’s 2018 FTA Excellence in Flexography Awards gold award-winning print, what exactly is depicted?
Oetjen: The front of our 2017 holiday-themed card has photos of the graduates from all four press operator courses in 2017, which are framed with a variety of differently colored and sized snowflakes. A pearlescent tactile varnish was printed on top of the snowflakes to make them pop. The back of the card highlights logos of all of the sponsors that make Flexo Tech possible. The inside of the card has a seasonal message and update about the program.
FLEXO: What design work went into the card? Were there any special considerations made with an eye toward the actual printrun and the press/consumables you would be using?
Oetjen: Preparing for the two separate varnish plates (one high gloss over the pictures and text and a tactile over the snowflakes) in prepress was a bit tricky, but we made it work. The snowflakes were individual complex objects, so getting them to knock out behind the images took some serious time.
We made sure to optimize and fingerprint the press in preparation for the run. This allowed us to know what to expect and gave prepress the info they needed to set up the files correctly, make curves and select the proper plate screening. In the pressroom, it allowed us to assure we were using the best set of components to achieve our desired print requirements.
Optimizing the plate screening for the different anilox rolls was critical for getting good print results. The tactile was tricky because we applied a 5 percent screen (it was not a solid) to help get the textured feeling we wanted. Without the fingerprint, we would not have been able to pull that off.
To prevent print variation, we did a spot green on the cover instead of a four-color process build and to avoid gear marks, used 0.5-in. wide bearer bars on all plates.
Job Details
FLEXO: On what type of press was the card printed? What was its width and the web’s width? At what speed was the job run?
Oetjen: The card was printed on a Mark Andy Inc 2200 13-in. press (22 years old) using 11-in. wide material. Because of the high volume (28 bcm) of tactile varnish applied, we needed to keep the speed at less than 100 fpm to allow for the ink to completely cure.
FLEXO: What substrate was used? Was it coated or uncoated? What point size was it?
Oetjen: Avery Dennison supplied us with 11-in. wide C1s 8-pt. tag stock.
FLEXO: What type and thickness were the plates used for the card?
Oetjen: They were Kodak NX plates, 0.067-in. thick.
FLEXO: What type of ink system was used? What type of metering system was used?
Oetjen: We used Flint Group’s EkoCure XS (UV LED) ink and a pearlescent UV varnish for the tactile. A single reverse-angle doctor blade was used. Daetwyler supplied us with Pearlstar blades.
To get the proper tactile feel, we did not use a traditional doctor blade. We took a plastic hose (used to drain ink back into the container) and put that in the doctor blade holder. This “buttered” the anilox roll instead of shearing off the excess ink, and allowed for a thicker yet controlled ink film to be delivered to the plate.
“To get the proper tactile feel, we did not use a traditional doctor blade. We took a plastic hose (used to drain ink back into the container) and put that in the doctor blade holder. This “buttered” the anilox roll instead of shearing off the excess ink, and allowed for a thicker yet controlled ink film to be delivered to the plate.”
FLEXO: How many print stations were used and what were the specifics of the anilox at each?
Oetjen: We printed the inside on station one, then used the turnbar to flip the web and print the front, using seven print stations (see Chart 1).
FLEXO: Were any special effects like a tactile varnish used?
Oetjen: We used a gloss varnish in station seven and a pearlescent tactile in station eight.
FLEXO: What were the influencing factors when choosing the inks, aniloxes, doctor blades and plates used for the card’s printrun?
Oetjen: We optimized and fingerprinted our press. We 4-color process optimized for the best components and identified the screening to be used on our plates. Different plate screening was applied for the 4-color process, spot and tactile plates because of the different ink film supplied by the anilox roll volumes. The fingerprint samples were analyzed by Kodak to identify the optimal screening for each anilox roll configuration. We also did a 4-color process fingerprint to determine target densities and adjust dot gains with the selected screening, as well as perfect the tactile varnish application.