Multi-Color Water-based Paint
Over the years, improvements in product formulation have made multi-color a good choice for a variety of surfaces. Multi-color is a 100% water-based product that meets VOC standards, dries quickly, and has little or no odor. Technology has made this product an excellent decorating option with none of the limitations of its predecessor.
– a method of applying a solid base coat then topping it with a sprayed dot-pattern finish – was frequently used on military vessels. Although specified for its durability and good looks, the early multi-color coating systems were highly combustible and had very strong odors. Application had to take place during off-hours, or areas to be sprayed had to be unoccupied until the paint was dry. As a solvent-based product, it was also difficult to clean up and had a very limited shelf life - sometimes lasting only hours after it was mixed. Environmental concerns over the disposal and clean up of solvent materials also caught up with multi-color as well as other solvent-based coating systems. Not surprisingly, multi-color lost its appeal with contractors and specifiers.
But over the years, improvements in product formulation have made multi-color a good choice for a variety of surfaces. Today’s multi-color is a 100% water-based product that meets VOC standards, dries quickly, and has little or no odor. “Multi-color is a completely different product today,” says Joe Insalaco, senior vice president of Aquafleck 100% Acrylic Latex Multi-Color, a division of California Products Corporation. “Technology has made this product an excellent decorating option with none of the limitations of its predecessor.”
In fact, the product is gaining in popularity again and an increasing number of architects specify the system because it provides a seamless look that can’t always be achieved with wallcoverings. Specifiers also have the ability to select the base and pattern finish in virtually any color thanks to computerized color matching. “Before any job begins, we includewith each order a color strike-off so the painter or architect can assure color matching,” Insalaco says. Computerized matching also makes good touch-ups possible. “If the surface gets damaged, architects and paint professionals know they can get the exact colors they need so touch-ups blend,” says Insalaco. “You can’t get the same results with most wallcovering repairs due to variations in dye lots.”
In addition, high quality spray guns make re-creating the original pattern arrangement possible. “Trained painting professionals have no problem achieving the pattern finish when they use the same equipment for touch-ups,” explains Richard Wheway, market manager of ITW Binks, manufacturer of contractor spray equipment. According to Wheway improved technology in spray guns have made the painter’s job easier. “We expect to have an airless system available in the spring that will provide an even faster way to apply the coating without the overspray common in conventional spray systems,” Wheway says. And, since airless spray also provides better control, replicating patterns during touch-ups is improved. With some multi-color systems, touch-ups can be done by hand. Scuffmaster multi-color finishes, a line of products developed by Master Coating Technologies, can be touched-up with a soft-bristle brush or by using a hand -held sprayer, according to Jennifer Nieters at Master Coating Technologies. “Painting contractors can touch up small areas quickly and easily with minimum equipment,” remarks Nieters.
The excellent durability of multi-color makes it ideal for application in high traffic areas such as hospitals, schools, offices, restaurants, shopping malls and entertainment complexes like stadiums and movie theaters. The slight texture of multi-color provides several advantages over a solid coat of paint. “Smudges don’t show up as readily and the additional layers of the pattern finish offer a thicker film build making it very scrubbable,” says Insalaco. Keep in mind however, that product formulations differ from manufacturer to manufacturer so paint professionals should check with their supplier on the durability of each product. Durability also contributes to the application of multi-color in indoor and outdoor settings. “Multi-color is a very versatile system - it’s at home on file cabinets and lockers as well as hospital corridors and office reception areas,” Insalaco notes. Multi-color is suitable for application on a wide range of substrates such as drywall, concrete block unit, metal, ceramic tile, and glazed block. The coating can also be used on textured surfaces such as stucco, but is not recommended for fabrics.
Another characteristic of today’s water-based multi-color is that its low odor allows application during normal business hours without disrupting building occupants. Low odor coupled with high durability frequently wins multi-color the specification and plays an integral role in the success of the job. Joe Insalaco sites one large-scale job where this was the case: the renovation of main concourse areas of the Salt Lake City International Airport. The painting contractor was given the challenge of repainting the laminated wall panels that line the corridors throughout the airport without disturbing passengers or personnel with paint fumes. Due to the high traffic of the airport, the job also required a coating tough enough to sustain frequent cleaning and abrasions from airport equipment and accidental bumps and scrapes from suitcases. “Multi-color proved to be an excellent coating for the job,” notes Insalaco. “The contractor was able to work without interruption. The durability of the product also reduced the need for frequent touch-ups.”
A variety of patterns from dots to string-type schemes have brought multi-color more notice among decorators and designers. “Multi-color offers a wide-range of looks depending on how it’s applied and the colors selected,” Nieters says. “Designers have a lot of freedom in determining what kind of effect they are trying to achieve from subtle tone-on-tone to more dramatic patterns with contrasting shades.”
One trend among decorators is the use of metallic and pearlescent multi-color. Often specified for accent areas like doors and trim work, metallic and pearlescent shades are used in settings ranging from nightclubs to corporate offices.
Several considerations play a key role when it comes to estimating material quantities accurately. For example, contractors need to consider the type of substrate that will be coated, application technique (which will vary from manufacturer to manufacturer), primer materials needed, base coat, a specific pattern style selected for the job and the colors used to create it. Inspecting a sample of the actual pattern style chosen for the job will help determine specific colors, particle sizes and densities. Also keep in mind any special effects such as a decorative clear coat that has been specified. And, like any other job requiring deep or bright colors, additional coats will be needed to obtain the desired shade. Manufacturers can be especially helpful at this stage since they can offer specific information on spread rates and cost estimates per square foot. Finally, consider ordering extra material (about 5-10%) in case additional paint is needed while the job is in process and as a leave-behind for future touch-ups, if necessary.
Labor costs should include adequate time for surface preparation. Base coat application with brush, roller or spray is typically a single step. Applying the pattern finish however, may require one or several spray coats depending on the density of the design and number of colors used. Again, multi-color manufacturers can provide valuable input on how many steps will be needed to achieve the pattern finish. Also include time for set-up and clean-up and note additional charges for color changes made by the customer.
Equipment needs are also an integral part of the final estimate. Multi-color coatings are applied using a combination of regular spraying or rolling equipment along with specialized spray equipment and nozzles made for multi-color applications. In some cases, proprietary equipment must be used. Master Coating Technologies for example, requires contractors to use proprietary equipment when applying their products. “Our spray systems have been developed especially for use with our products. They complement each other,” explains Nieters. “We also provide hands-on training sessions for painting professionals to assure the best results.”
Without doubt, the most important step in the application of any paint material is surface preparation. All manufacturers agree that without adequately completing this step, product performance cannot be guaranteed. Several factors come into play when properly preparing the surface. These include type of substrate, surface contamination and imperfections, and climate conditions.
Most substrates such as concrete block units, wood, drywall or metal require some type of primer coat as part of the entire application process. Of course, the type of primer used depends on the substrate: block fillers for concrete, acrylic high-solid primers for drywall and so on. When in doubt, always check with the manufacturer for guidelines.
Eliminating moisture is the first important step in surface preparation since it is the cause of the majority of paint failures like blistering, peeling and flaking. In addition, make sure that any other substrate that comes in contact with the surface to be painted is also dry as moisture can be transported from one substrate to the other. Surface contaminants such as dust, dirt, peeling paint, oil and rust must also be cleaned away to provide a smooth, even surface. Other surface imperfections like rough spots and splinters must be removed by sanding or grinding. Hollow areas and ridges should be filled with compound and smoothed out.
Climate conditions also play into the ultimate success of the application. Exterior painting is best done in dry weather at temperatures between 50° and 85° Fahrenheit. If possible, avoid humid conditions.
Once surface preparation is complete, it’s simply a matter of closely following the manufacturers guidelines. Because each manufacturer has unique attributes built into their products, it’s important to follow their specific guidelines in the application process. “Applying the pattern finish like an ordinary paint just won’t work,” explains Wheway. “Trying to spray the multi-color finish coat at a very high pressure with an external mix nozzle set-up totally defeats the purpose of multi-color. What you end up with is a solid color.” To avoid this pitfall, check with the multi-color manufacturer for all equipment requirements. In general, Wheway recommends a compressor, pressure tank with dual regulation and an air spray gun with an internal mix nozzle set-up (see photo). Next, prepare the coatings you will need by carefully pouring them into one clean container (a method commonly referred to as “boxing”). Then, connect system components, making sure to follow all guidelines for proper compressor power, hose length and diameter, and nozzle/needle set-up.
The next step is the application of the pattern coat using the specialized spray equipment described earlier. Make sure the spray equipment is clean and working properly, then follow these steps as recommended by ITW Binks:
- Turn off the regulator and relieve pressure on the tank. Fill the tank with the prepared coating and tighten the tank cover.
- Let air pressure into the tank; 20-30 PSI is a good place to start. Completely open fluid and side port control knobs by turning them counter-clockwise.
- Introduce air pressure at the spray gun air inlet by triggering the spray gun slightly without actually spraying any material. Start at about a 20 PSI setting.
- Hold the spray gun from 15 inches to three feet from the surface, depending on manufacturer’s specifications. Begin spraying while in motion, keeping the gun perpendicular to the surface. Do not arc or wave the gun and always release the trigger at the end of the stroke. Use the cross-hatch technique (horizontal, then vertical passes) to ensure the best results and coverage.
- To obtain better texture and color separation, keep air pressure low. Working at increased air pressure will cause the colors to blend together and become smoother. Make sure to keep a record of the correct pressures as a reference guide.
- Keep pressures as low as possible to avoid overspray.
- Re-box any material that will be standing for more than 30 minutes.
With its performance characteristics, versatility and environmentally considerate formulation, multi-color is no longer thought of as an out-of-date coating system. Architects and designers have rediscovered multi-color for its ability to add subtle tone and texture to a variety of substrates. Paint professionals value the system for its durability and easy touch-up. “We’re finding that multi-color is replacing vinyl wallcovering in many settings because of the range of flexibility it offers in decorating schemes, and its ability to look good year after year,” observes Nieters. What used to be considered an industrial-type finish is now turning up in restaurants, casinos, hotels and corporate headquarters. From the sounds of things, multi-color has truly made a come back.