By Olivia Cahoon
Part 1 of 2
Digitally printed wallcoverings can be placed in environments where the final graphic is exposed to elements that contribute to mold and bacteria growth. Mold and bacteria damages graphics and creates potential health hazards. Media manufacturers offer protection solutions.
Environments at Risk
Containing modified starches, traditional wallpaper adhesives use water for activation. When wallpaper seals, it traps the moisture in the wall. “The starches now provide food for mold, encouraging mold growth and thus requiring additional anti-microbial pretreatment to prevent mold growth,” says Jason Yard, marketing manager, Mactac Distributor Products.
Anti-bacterial protectants protect from mold. “Environments with a lot of human interactions need anti-bacterial wallcoverings the most,” says Darren Speizer, VP, sales and marketing, Drytac.
Anti-bacterial wallcoverings are ideal for environments with critical hygiene requirements like animal facilities, daycares, cafeterias, hospitals, laboratories, nurseries, public restrooms, restaurants, and schools. It’s also suggested for humid environments that typically promote the growth of mold and mildew.
“Wallcoverings need to be cleanable to help maintain a sterile environment and allow for a better looking graphic over time,” offers Marcel Medved, business development director, Continental Grafix.
Treatments for wallcoverings are available as liquid lamination or as a protective hard coat overlaminate. According to Yard, protective treatments don’t affect printability or ink compatibility because the print media doesn’t get treated—just the laminate.
“Coating doesn’t really effect the printability after the treatment, if anything, it could increase vibrancy of the print and add to the overall durability,” agrees Jaimie Mask, product specialist, S-One Holdings Corporation.
Speizer says liquid lamination can be applied to wallcoverings after printing. Liquid lamination increases durability and allows cleaning agents to be safely applied to the graphic. For smooth surfaces, Speizer says anti-bacterial overlaminates can be applied to wallcoverings after printing but prior to onsite job installation.
“A Type II certified liquid laminate that is pre-applied is the most common, as most wallcoverings have texture, so self-adhesive laminates do not work,” offers Medved.
Embossed films also inhibit the growth of high-touch surfaces and are used as overlaminates. Dennis Brunnett, technical service specialist, FLEXcon, says that printing is not an option for embossed products because it alters the topography. Patterns within embossed film’s topography are arranged to form repeating micro-patterns to provide control for migration and microorganism growth.
“The surface of the patterns alone inhibits bacteria from attaching, colonizing, and forming biofilms of deadly bacterial pathogens—species which are resistant to antibiotics or typical anti-microbial coatings,” continues Brunnett. Embossed films can be used over print or applied directly to the surface.
Greg Maze, sales and marketing manager, Neenah Paper, recommends treating or coating the finished product after printing rather than pretreating. “This provides the best barrier protection possible for the intended end use application,” he explains.
Treating the finished product also helps protect against cross contamination rather than relying on a topical treatment underneath full coverage print. “While you can certainly load up a product with barrier coatings, ultimately it is the printed surface that is the final point of possible contamination,” adds Maze.
Wallcovering media with a protective treatment increases the product’s manufacturing costs because it requires additional processing. Mask says despite this, it allows print providers to factor increased durability and protection into the pricing.
Print providers using treated wallcovering media should be aware of installation challenges. Medved says that some installation materials may require butt seams. He advises print providers seek solutions that can be overlap seamed because the adhesive will stick to the treatment.
Safe and Sanitary
Primarily used indoors, digitally printed wallcoverings are a unique solution for enhancing areas but also pose risks for mold and bacteria growth. Treatments can be applied to prevent and protect against harmful effects.
Nov2017, Digital Output