By Melissa Donovan
With latex- or resin-based printers continuing to offer advantages in terms of durability and fast dry times, increased material compatibility becomes the norm. In terms of media designed for window graphics, both perforated and unperforated are available and optimized for latex/resin ink.
Above: Drytac Polar Blockout is an opaque printable blockout film ideal for two-sided window graphics and other blockout layer needs.
Get Educated
Latex or resin ink is a unique composition of chemicals and additives. As such, it presents challenges when printing to various media types.
Aarona Tesch, product marketing manager, GBC and SEAL, ACCO Brands, explains, latex or resin inks are water-based consumables and require a substrate with specific surface coatings to properly bond to the media. Not all traditional window films are coated to handle this.
For example, “clear film types were not inherently compatible with latex ink technology without the addition of a custom top coating,” several years ago, explains John Coyne, sales manager, Lintec of America, Inc.
In addition to lack of a proper coating, there are drying and curing challenges to be aware of. “Latex/resin ink tends to form a thicker layer on the media compared to solvent-based inks, for example. Unperforated films, in particular, may experience uneven curing or curing that results in poor print quality,” says Tesch.
“Some challenges may result from the high heat necessary to properly bond and cure latex/resin inks to the substrate. This can cause material to shrink or curl. These challenges can be addressed by establishing ICC print profiles for specific equipment, ink sets, and RIPs, in addition to printing only on those materials that are designed for print compatibility with latex/resin,” recommends Jason Maricle, product manager WindowMark perforated window film, General Formulations.
Not only must the proper coating allow the ink to bond correctly with the media, as well as dry and cure properly, how it reacts to installation needs to be considered. At Lintec, “it required several years of research and development to perfect a top coating that was stable and capable of accepting latex ink. This top coating would also require a level of durability that could protect the latex ink from the wet apply window film installation process,” shares Coyne.
Other issues include durability, optical clarity, and environmental resistance, adds Tesch.
However, “latex/resin technology has moved forward by leaps and bounds,” attests Dennis Leblanc, senior business development manager, North America, Drytac.
Product Options
To meet challenges head on, more window media vendors create window films specially designed/coated for latex and/or resin ink compatibility.
“Making these materials print well with latex/resin ink means some may require specialized film formulations, treatments, or top coatings to enhance their durability and printability,” states Maricle.
Continental Grafix USA, Inc.’s iTac White is an opaque white polyester (PET) film backed with a proprietary adhesive designed for interior and exterior applications on ultra-smooth surfaces. The low-tack adhesive allows iTac White to be installed wet or dry and is permanently removable without leaving residue behind. iTac White is universally compatible with solvent, eco-solvent, UV, and latex ink.
Drytac carries a large array of window graphic solutions, all with latex/resin compatibility. These include polypropylene (PP) and PET with hybrid, permanently peel-able and permanent adhesive solutions as well as blockout media to be paired with clear materials or synthetic blockout media paired with window mounting adhesives for push/pull graphics.
The entire portfolio of window graphic films at General Formulations—whether perforated or solid film, white or clear, and even the total blockout materials—are all compatible with latex/resin inks.
Lintec invested a substantial amount of time and money in a latex ink compatible, optically clear window film development process. In keeping with the company’s sustainable theme, non-vinyl films were preferred, which Coyne admits proved more difficult than expected. In addition to these requirements the film needed to have true optical clarity, for which Lintec is known. The company’s E-3000ZC latex film meets and exceeds all of these expectations.
Nekoosa’s PVC-Free Sign-Ad Clear is a 4-mil, gloss, clear film designed with a removable window adhesive and 90# layflat release liner. It features an enhanced top coat for latex and UV wide format printing with outdoor durability up to four years. The film removes without leaving adhesive residue behind.
Newlife Magnetics, LLC’s Cling King print media features a high-quality PET print surface with a smooth, silicone coating on the back that allows it to stick to any smooth non-porous surface just like a suction cup. It is repositionable and residue free, even after long-term installations. Available in white and clear versions, the clear version is optically clear and ideal for window graphics where you don’t want to see anything but your printed graphic. It is printable with solvent, UV, and latex ink.
SEAL UltraClear PET, from ACCO Brands, is a 4.9-mil optically clear PET film that can be used for many different graphic and design applications. It has a unique ultra clear silicone adhesive that is both repositionable and removable. This product is great for architectural design, including glass office partitions, point of purchase and retail signage, and window graphics. It is designed for use with solvent, eco-solvent, latex, and UV-curable inks.
Media Types
Breaking down options, popular types of media used for window graphics include PP, vinyl or PVC, and PET. All of which—when properly manufactured or treated with the correct coating—can work well with latex/resin ink.
“PP, PVC, and PET are among the best-suited media types for latex and resin inks, with PET offering the highest quality and durability, especially for premium applications,” says Tesch.
According to Leblanc, “all of these materials are suited for window graphics and all have their own pros and cons.”
PP
PP is popular for multiple reasons. Tesch says this is because of its excellent printability, dimensional stability, and cost effectiveness. “It features a smooth surface that works well with water-based inks, providing vibrant colors and sharp details. Additionally, it is lightweight and resistant to moisture, making it suitable for indoor and short-term outdoor applications.”
Each material has advantages and disadvantages. “PP is a good dimensionally stable material for shorter term graphics that may at some point fit into recycling streams, however don’t have the ability to conform to irregular surfaces, which is where possibly a vinyl would perform better,” admits Leblanc.
PP is considered “excellent” for unperforated window films, says Tesch. It is not commonly used for perforated “due to structural and print quality considerations.”
PVC
Vinyl, when coated or specialty treated, works well with latex and resin inks.
Although, Maricle believes “vinyl is best suited for latex/resin inks and doesn’t require any additional surface treatment/top coating for printability.”
It’s used for perforated window media options, notes Tesch.
PET
PET is used quite frequently. “PET has the best clarity in my opinion across all medias and very good durability however, conformability may be an issue,” states Leblanc.
To achieve conformability, “PET media alternatives typically require a surface treatment or top coat to ensure proper ink adhesion to the surface of the film,” says Maricle.
Excellent dimensional stability, durability, and clarity are three reasons why users prefer PET for latex and resin ink, according Tesch. Additional benefits involve resistance to moisture, chemicals, and UV light.
Tesch also considers PET-based media “excellent” for unperforated window films.
Latex/Resin Optimized
It can be challenging to print with latex/resin ink to traditional window media—whether perforated or unperforated. However, media options available today—PET, PP, or PVC—are designed to perform optimally with this ink set. Many of these products are top coated with a special formulation to ensure success. Each vendor offers its own twist.
Nov2024, Digital Output
