Silkscreen Reigns Supreme
Meeting rough applications is as smooth as silk for screenprinted labels
By Maggie DeWitt
A rubber squeegee pushes UV-cured ink through a fine mesh screen mounted onto a steel frame, laying down thick layers of color. The result is the toughest label on the market. And while some newer printing processes are starting to encroach on traditional silkscreen territory, none of the contenders can take a licking and keep on sticking quite like screenprinted labels.
"Flexo and digitally-printed labels look and feel almost exactly like screenprinted labels," said Mike Evans, marketing manager for Lancer Label, Omaha, Neb. The difference, he added, is in screenprinted labels' incredible durability and longevity in the face of environmental assaultsespecially harsh sunlightand the flexibility to handle wider formats and special shapes of all the printing processes, screenprinting deposits the thickest film of ink on a substrate and it is that film's thicknessas well as the type of colorant the ink containsthat chiefly determines the durability of label images.
Even a laminated offset or letterpress label will not stand up to sunlight like an uncoated screened label.
"Lamination forms a protective barrier against moisture and abrasion," said Evans, "but it doesn't shield the image on the label from the deteriorating effects of sunlight." However, the solventless, UV-cured screenprinting inks provide a colorfast image that lasts over timethree to five years is the average life span for screenprinted images of non-neon pigments.
In addition, most screenprinted labels are produced on weatherproof and waterproof vinyl and polyester substrates which offer dimensional stability.
Although the lightfast, high-gloss screenprinting inks are very resistant to chemicals and abrasion, an overlaminate can be applied to labels exposed to extremely harsh environments. Besides the additional protection, this imparts an aesthetically appealing overall sheen to the labela value-added feature for marketing purposes on consumer goods.