By Melissa Donovan
The June issue of Digital Output includes content on short-term wallcoverings and how to cut wallcoverings. Continuing our wallcovering coverage, this article looks at liquid coatings for wallcoverings. While laminate is an option for digitally printed wallcoverings, liquid coatings provide benefits from protection to achieving certain aesthetics.
Short-Term Looks
Digitally printed wallcoverings are used in a number of environments from hospitality to retail.Depending on where they are installed they may be in place for six months or two years. In regards to short-term wallcoverings—those installed for less than 12 months—it’s questionable whether an additional coating is needed.
While most short-term wallcoverings are not coated because of the nature of the lifecycle and addition of unnecessary costs, Michelle Kempf, VP, sales and marketing, Continental Grafix USA, Inc., says the environment and amount of foot traffic, as well as the type of wallcovering chosen all need to be considered prior to making a final determination.
“Ultimately, the decision to coat a short-term wallcovering depends on the specific requirements of the application and the desired lifespan of the wallcovering. If a coating is desired, it’s important to choose a product compatible with the wallcovering material and will provide the desired level of protection without compromising the appearance or functionality of the wallcovering,” advises Mike Richardson, business development manager – graphic media, Jessup Manufacturing Company.
Roy Ritchie, president, DreamScape, explains that short-term use implies that damage over time is less likely, which means short-term projects could probably function without a coating. However, two critical contributing factors determine whether a coating is useful—ink adhesion and the location of the install.
“There are many durable base materials available to digital printers, but what typically necessitates the use of some form of overcoat is the lack of abrasion resistance in the ink on the surface of the material. Simply put, you don’t want the walls to scuff too easily so the ink needs to be bonded well to the base wallcovering, and if it isn’t sufficient then a coating can provide extra security,” shares Ritchie.
Based on findings from DreamScape, wallcoverings printed with eco-solvent, mild solvent, and some latex inks can be more susceptible to abrasion, as well as any ink system that hasn’t properly cured.
“In regards to short-term wall applications, it all depends on the ink and substrate being printed. For example, if you decided to print with an aqueous-based ink on certain medias they may scratch easily. We recommend that you coat to protect the life of prints,” notes Syd Northup, VP of digital, US, Marabu North America.
While most of today’s wide format inkjet printers utilize durable inks for short-term use and also colorfast to UV light exposure, Ross Burnham, senior product manager, Mactac Graphic & Signage Solutions, believes coatings can still be used to change the finish or make the finish a more uniform matte.
When it comes to location of the install, Ritchie says it depends on the amount of traffic in a particular space and the activities taking place in the space. “For example, if the walls are exposed to heavy traffic or other conditions where abrasion can be a problem, such as an airport, restaurant, or hotel hallway, we recommend the application of a top coat.”
“In general, additional coating is not required for short-term wallcoverings unless there is a specific requirement such as scratch resistance in a high-traffic area or a need for a specific finish,” agrees Peter Bourgeois, territory sales manager, Drytac.
Richardson says if the wallcovering will be exposed to heavy traffic or handling, a protective coating helps to prolong its lifespan and maintain its appearance.
In place for either short or longer durations, for certain projects that require a true Type II commercial durability, Ritchie recommends a coating either way. But, he points out that there are several proven combinations of DreamScape wallcovering material with EFI and Canon Solutions America printer technologies that achieve Type II Results without the extra step of a top coating.
“Hospitality environments requite a Type II durability wallcovering, some meet this without coating while others require a coating to meet this standard,” adds Steve Yarbrough, customer experience manager, Neschen Inc.
Apply It
Coatings are applied manually via a number of methods—spray gun, roller, or paint brush. Automated devices like laminators or spray booths are also options.
“The most cost-effective way to apply a coating depends on a variety of factors such as the size and shape of the surface, the type of coating, and the equipment and resources available,” shares Anna Zieba, marketing specialist, tapes, labels and coatings, H.B. Fuller.
Viscosity influences how to apply a coating, according to Northup. “If you hand apply—rolling is most common—we may suggest a liquid laminate with a thicker viscosity. If running a roll-to-roll liquid laminator, the coating needs to have a different viscosity since it is applied with a mayer rod.”
A laminator like Marabu’s StarLam 64-inch device is cost effective in that it features a double filtration system that recirculates the coating while running. “So, when you are finished coating for the day, liquid laminate can be put back into containers for future use,” explains Northup.
“In some cases automating the coating process can help increase efficiency and reduce labor costs,” notes Zieba.
Another option is a pneumatic sprayer. “It can control the amount of liquid sprayed to a printed substrate,” says Northup.
Ritchie suggests applying coatings like its DreamGuard ProTex3 product with a .25-inch low-nap paint roller either before or after installation.
But, it is only cost-effective if the operator is knowledgeable in the process. “Properly trained staff can help ensure the coating is applied efficiently and effectively, reducing waste and minimizing the need for rework,” recommends Zieba.
Other tips Zieba provides in terms of how to practice cost-effective coating methods is using the proper coating products and following manufacturer’s instructions.
“Using high-quality coatings may cost more upfront, but they can help reduce the need for rework and maintenance down the line. Following the manufacturer’s instructions for surface preparation, application, and drying times can help ensure the coating is applied correctly and provides the desired protection,” she adds.
Universality
The type of wallcovering materials digitally printable today range from vinyl to film, fabric, and paper. Universal coatings are available that work best with all of these mediums—within reason.
DreamScape DreamGuard ProTex3 is formulated to work well with just about any vinyl wallcovering materials—not just DreamScape. Likewise, Ritchie says Marabu’s liquid coatings work well with several DreamScape wallcovering products like its Matte and Terralon lines.
DreamGuard ProTex3 increases abrasion resistance about five times with the application of one thin coat. Offered in satin and matter finish, it is used for solvent, eco-solvent, and UV digital prints.
Marabu ClearShield Professional Wall Armor is compatible with latex, eco-solvent, and UV-curable ink. It also has the benefit of adding a Type II certified solution for commercial applications. When applied, the liquid laminate creates a protective barrier for scratch, UV, chemical, and stain resistance.
Both DreamGuard and ClearShield are water-based coatings, which Burnham believes “is the best option because of conformability, uniformity, durability, and compatibility.”
Zieba admits that “it is generally preferable to use a coating specifically designed for the specific type of media. This is because different wallcovering materials have different properties and may react differently to various types of coatings. For example, a coating that works well with vinyl wallpaper may not work as well with fabric wallpaper or adhesive wall decals. Using a coating specifically designed for a particular type of media can help ensure compatibility and provide the best protection and longevity for the wallcovering.”
Liquid Coatings
Commercial, retail, or residential; consumer, designer, or brand owner—no matter who the customer is, print providers need to understand their wallcovering needs and with that whether a liquid coating is beneficial to the end result. While shorter term applications don’t require a topcoat, there are many instances when they would benefit.
“Wallpapers have become a very popular do-it-yourself material thanks to their ease of use and great impact on the area users have been updating. They provide various choices, with many being easily removable to ensure no wall damage. Wallcovering manufacturers consider all of those preferences when looking for the best coating or adhesive system for their products,” shares Zieba.
Jun2023, Digital Output
