A long-established printing technique, silkscreen reigns supreme over the durable label market.
Ancient Egyptians were using papyrus stencils and pigments to duplicate images as early as 2300 B.C. However, modern screenprinting likely stems from patents applied for in the early 1900s. And except for the introduction of photographic stencils around that time, and the impact of computer technology in the '80s, the process remains relatively unchanged.
So does the fact that a screenprinted label is the most durable product on the market. "The key," explained Mike Evans, marketing manager for Omaha, Nebraska-based Lancer Label, "is that compared to other printing techniques, screenprinting lays down the thick deposits of ink for unsurpassed durability."
While over-laminates will strengthen a substrate and offer protection from moisture and abrasions, they will not prevent inks from fading due to sunlight. Yet, even without a protective layer, colorfast ultraviolet (UV) screenprinting inks—combined with polyester or vinyl substrates and permanent adhesives—can weather the harshest environments.
Said Bob Roeda, president of Screentech, South Holland, Ill., "Manufacturers usually guarantee screenprinted labels for one year, but these products typically last up to four or five years."
Roeda noted that not all screen inks are UV-cured. Some conventional inks air dry and will fade over time. Ultraviolet inks, on the other hand, are innately rich and glossy and the curing power of the UV dryer ensures the durability of those vibrant colors.
Evans reminded distributors that when selling these products they must take into account whether the customer needs roll or sheeted label products. "If the label will be auto applied, a roll format is necessary to accommodate the application machine. These labels must be produced with special attention to the die cuts in order for them to come off the liner properly," he said.
Labels, decals and stickers that are more consumer oriented or promotional in nature are typically sheeted applications, and require a thicker liner. "With sheeted products it's essential to select the correct liners to prevent the sheets from curling," Evans said.
Screenprinting is ideally suited for bold coverage and brilliant images, and it adds a pleasant, tactile dimension to prime labels on consumer products.
As a result, Bob Yates, a California-based sales manager for the Swiss label press manufacturer Gallus, observed that screened labels are frequently found on health and beauty products, household detergents and wine and spirits bottles. "Using a clear substrate on a clear bottle is a great way to really make images pop," he said.
But as Evans pointed out, "The distributor's best opportunities for marketing screenprinting are definitely in durable industrial labels and promotional products."
For instance, Screentech serves profitable niche markets within garbage and trash collection facilities, portable toilet manufacturers, recyclers and rental companies, where company names or logos, in addition to contact information, warnings and maintenance instructions, need to be displayed. It is screenprinting's superior outdoor performance that enables these products to endure over time, despite sunlight, moisture and rough handling.
With less costly set-up involved, screenprinting is usually indicated when dealing with lower quantities—Roeda has had orders for as few as 12 pieces. "But even for quantities of more than 1,000 where offset or flexo might be more practical, it must be screenprinted if the label is going to be exposed to the elements," said Roeda.
Screenprinting also offers tremendous flexibility in producing large and odd-sized labels and decals. Unlike flexo and offset printing, there are few size restrictions to contend with, and accommodating unusual shapes with screenprinting is more cost effective.
"Digital printing is starting to capture a greater segment of the large format, ad specialty and point-of-purchase markets," Roeda observed, "but it lacks the coarseness and density of UV screenprinting, which adds that slightly raised quality consumers find appealing—and, of course, the durability."
With smaller dots than screenprinting, flexo printing does display a greater degree of definition required for high-end graphics. However, Roeda observed that screened label designs are often quite dramatic. Still, he cautioned distributors to check with their suppliers when artwork is highly detailed.
While the screenprinting process itself may be little changed, developments in inks and equipment are yielding exciting results and prompting new applications.
Recent modifications in acrylic-based inks allow more organic qualities to be achieved. Yates explained that special additives will produce a unique and creative tactile relief pattern or a braille effect on labels. This technique can be used with a variety of substrate materials to add an extra dimension to graphics, highlight a logo or create a decorative grip panel.
In addition to enhancing aesthetic appeal, the process provides practical opportunities for use with the visually impaired—including warning labels on chemicals and household products—as well as on signage and in publications. Other options achievable by this method include fine line work, solid area motifs and metallic and embossed effects.
By Maggie DeWitt