Primers are changing in the wake of new laws regulating VOC content. by Christina Camara
Paint manufacturers have been in overdrive for several years, creating new products to meet tough air-quality regulations.
Nearly all paints have had to be reformulated to emit fewer volatile organic compounds (VOCs) into the air. Low-VOC primers are entering the market more slowly. Since many water-based products are still acceptable, contractors tend to stick to the same tried-and-true products they have always relied upon. In many cases, the latex primers will perform as well as oil-based products, if not better, according to the Paint Quality Institute.
But there are some situations in which an oil-based primer is a must. Oil-based primers can hide heavy water and smoke stains that latex primers can’t handle. They help paint adhere better to chalky surfaces, and woods that are particularly susceptible to tannin bleed-through — cedar for example — need the stain-blocking properties of an oil-based primer.
Dick Hardy, president and owner of XIM Products, Inc., a Westlake, Ohio manufacturer of bonding sealers and primers, said manufacturers basically have three options when they want to take a high solvent-containing primer, such as an oil alkyd, and lower the VOCs. VOCs include paint thinner, mineral spirits, alcohol, gasoline, ethylene glycol, acetone and xylol. One option is to increase the solids and decrease the solvents, with the advantage being that the new primer will perform similarly to the older version; another option is to replace the solvents that are unacceptable with ones that are still OK under the law, but the primer will smell and look different, and the application properties won’t be the same. The third option is to switch to a water-soluble system.
“Necessity is the mother of invention, and it has forced the paint industry to make a shift, even though the cost of doing so, I believe, has been pretty high for the industry,” Hardy said. “In other words, it is not so easy as the regulatory people think to go out and reformulate coatings that work equally well and apply equally well and end up with the same performance.”
Tim O’Reilly, category manager at Zinsser, said creating low-VOC, oil-based primers has turned out to be a huge technical challenge for some companies. Early formulations were costly and didn’t perform well. The entire industry is finding that the technology isn’t evolving as quickly as the laws are.
Going, going, gone
While tough national standards were established in 1998 to reduce the amount of VOCs in paint, individual states or air quality districts are creating their own regulations.
O’Reilly said Zinsser produced its High Hide Cover Stain in advance of 2003 regulations for the South Coast Air Quality Management District (SCAQMD), which basically covers California’s Los Angeles basin and Orange County. O’Reilly believes it is the best low-VOC specialty primer on the market.
More challenges lie ahead. O’Reilly said the SCAQMD is phasing in another reduction so that VOCs in primers will be limited by July 1, 2006 to 100 grams per liter, which is even lower than that of many water-based primers. The change will basically eliminate the use of oil-based primers in that area, which means that with the exception of using pigmented shellac to cover heavy water and smoke stains, only less-effective, water-based products will be available. Shellac, which is made from the resin produced by the lac beetle, is a natural resource in limited supply. “Shellac resources could be tapped out just to address the needs of the south coast,” O’Reilly said.
Regulations elsewhere are less restrictive, and the industry is hoping Southern California’s rules will not be used as a model in other places.
But as Hardy put it, “the train is rolling,” and low-VOC products are the paints and primers of the future. Water-based systems are improving rapidly, but some sacrifices in quality will need to be made as states push their VOC limits lower and lower. For example, most latex primers and paints contain propylene glycol, which allows the paint to go through several freeze-thaw cycles unharmed. As the VOCs go down to 100 grams per liter, instability increases. A can of low-VOC paint or primer that has been exposed to freezing weather turns into an unusable mash of what looks like cottage cheese.