Facts, History & Maintenance for Optimizing Performance of Dry Erase Walls
It may come as a surprise that writable-erasable paint has been in use for over a century. In the early 1900s, cured enamel paint served as the writable-erasable substrate for grease pencils. Any hard, dense, cleanable, non-porous, stain resistant paint or coating can be used as a writable-erasable surface for grease pencils and the more recent development, the dry erase marker, introduced in 1975. Polyurethanes commercially sold beginning in the 1960s and polysiloxanes introduced in the mid-1990s have both been used, sold and promoted as writable-erasable surfaces since the mid-1990s.
Two 1990s Documented Writable-Erasable Coating Projects with Ameron Performance Coatings
Ameron International’s development and introduction of its patented polysiloxane hybrid coatings in 1994 under the commercial name PSX 700 made “Cleanable, Stain Resistant and Graffiti Resistant” a component of the commercial promotion of performance coatings. Within two years, Ameron, Southern California Edison and Bechtel were specifying and installing PSX 700 polysiloxane coating on the interior control room walls, desks, panel sections and operation consoles of San Onofre Nuclear Generating Station to achieve cleanable, writable-erasable surfaces. The 1996 application of PSX 700 at San Onofre was likely the first application of a polysiloxane coating as a writable-erasable surface (dry erase surface). The original writable-erasable surfaces created with PSX 700 in 1996 were still in use and in excellent condition when San Onofre was closed in 2013.
Ameron also sold through distribution partner San Diego based Frazee Paint the polyurethane coating used to create writable-erasable walls at MP3.com in the late 1990s. The project was specified by MP3.com for the Eastgate Mall, San Diego, California headquarters. The application was done by MC McMurray Painting. A polyurethane was chosen for the MP3.com project due to adhesion concerns with the PSX 700 polysiloxane coating, as the walls for installation were gypsum-board (drywall) and sealed with an acrylic emulsion architectural paint, the cohesive strength of the PSX 700 was believed so strong as to damage the existing paint and drywall.
Requirements of Dry Erase Paints and Coatings
A dry erase paint or coating must be made of a performance resin system that forms a dense non-porous film with good to excellent ink release properties to be erasable. The coating must be able to be applied to a smooth vertical surface by roller or spray application. Dry erase paints and coatings should be flexible enough to be applied over acrylic latex painted surfaces and dry wall without damaging the substrate.
Dry Erase Paint and Coating Selection Includes Safety, Environment and Performance
Safety must be considered in selecting a dry erase paint or coating for installation in occupied space. Two component polyurethanes contain an activator known as an isocyanate and require specialized breathing apparatus for the coatings applicator as well as the evacuation of interior structures when such chemistry is used (See OSHA Instruction CPL03-00-017 National Emphasis Program – Occupational Exposure to Isocyanates). Industrial solvents, strong odors and high VOC are also not acceptable in occupied space thus most high solvent content epoxies and moisture cured urethanes should be avoided.
Polysiloxane coatings are high solids, LEED compliant, contain little solvent and are low odor during the application and cure process. Precision introduced a flexible version the polysiloxane resin system known as EeZeClean Dry Erase Paint in 2011 following more than seven years of success with commercial applications of polysiloxane coatings on interior walls and surfaces for improved cleanability.
Dry Erase Pens and Dry Erase Markers
Dry erase ink markers are similar to permanent ink markers in formulation of the inks with the exception that the dry erase ink includes a surfactant that makes the ink more erasable while the surfactant exists in the ink film. Once the surfactant dries out of the ink film, which takes a few days or even weeks, the ink is relatively permanent on most surfaces. To remove the dried ink or for that matter the ink of a permanent marker, you can write over the original ink with a dry erase marker and the surfactant will penetrate the film and the ink will once again be erasable. You can also use a dry erase cleaner, isopropyl alcohol or a commercial cleaner such as Krud Kutter® Original as long as the dry erase paint or coating is chemically resistant to such solvents.
Cure Time, Optimizing Performance, Maintenance
Ghosting and stains on dry erase coated surfaces have three causes:
1. Not fully cured
2. Needs to be cleaned
3. Dry erase coating film is not robust enough to resist dry erase ink staining
Cure times to writing with a dry erase marker vary with the type of coating, thickness of the coating, temperature, air flow and humidity at the time of application and the following seven to fourteen days. Most dry erase coatings can be written on at five to seven days at 70 degrees with good air flow, but if ghosting occurs, a dry erase cleaner, isopropyl alcohol or a cleaner such as Krud Kutter® Original can be used to remove the ink, the ghosting and clean the entire board. It is a good practice to test a small area of the dry erase coating before using any of these cleaners/solvents to ensure you are not damaging the dry erase coating film.
Dry erase coated surfaces need a regular cleaning to remain dry erase. On walls that are used daily or with dry erase markings that have been up over four days we recommend you should consider cleaning weekly with a micro-fiber cloth and a cleaner such as a dry erase cleaner, isopropyl alcohol or Krud Kutter® Original. As we suggested earlier, the cleaner/solvent should be tested on a small area of the dry erase coating to ensure it does not damage the dry erase coating film. Never use an abrasive cleaner to clean a dry erase coating.
Professional Application = Professional Results
Dry erase coating application should be done by a performance coatings professional with the equipment, knowledge of safe chemical handling and the skill set to do a professional application. The coatings professional is responsible for over 70% of the success of a dry erase coatings application. Such an application requires surface preparation to ensure the wall is smooth and the surface is tightly adherent to the substrate. The professional applicator has mastered the technique for roller or spray application of the dry erase coating system and has the equipment to safely and properly perform the dry erase coating application.
The best performing dry erase coatings are LEED compliant, high solids, low odor, low VOC, chemical resistant, polysiloxane coatings designed for occupied space application. The polysiloxane coatings designed for application to sealed dry wall form a hard ceramic like film that results in easier cleaning of the surface even when dry erase ink is left on the surface for more than the recommended four days. In our testing, one area done with Expo® and Foray® markers in reds, blues, greens and neon colors went eight weeks and was still easily erased with a dry micro-fiber cloth. Since the chemical resistant polysiloxane coatings are weatherable and do not chalk, polysiloxane dry erase coatings can be used on exterior surfaces. – Nye Miller, Pacific Southwest Coatings
Nye Miller is a senior technical sales representative for Pacific Southwest Coatings with over 36 years of performance coatings technical sales experience. As an employee of Ameron International, Nye Miller worked with Southern California Edison, Bechtel and Frazee Paint on the writable-erasable coatings projects that are described within the article. EeZeClean is a dry erase paint manufactured by Precision Coatings and available outside of the U.S., Canada and Mexico.
In the United States and Canada we recommend FUZE from MDC. Contact MDC or call 800.621.4006.
Precision Coatings manufactures high performance finishes based on innovative polyurethane and polysiloxane technologies. Precision Coatings utilizes high grade resins and automotive grade pigments to produce extended life cycle finishes that meet the needs of architects, designers and specifiers.