Latex, and Painters, Lose Solvent-Generated Odors

Until recently, a strong odor in latex paint was like a lot of things in life--unpleasant but tolerable to get the job done.

But things are changing.

The primary odor-causing agent in latex paint is solvent, but today you can buy low-odor interior latex paint that is essentially solvent-free. And industry experts say that low-odor exterior paints should debut in the near future.

Certainly this is a boon to painters everywhere who are sensitive to chemical odors.

The problem is telling the difference between paints that are nominally low-odor because they meet federal specifications for solvent content and new varieties of paint that have almost no solvent.

A can of high-quality latex paint contains a 20% binder by volume. In traditional latex paint, there is 1% to 7% solvent dissolved into the binder.

New low-odor varieties of latex paint are essentially solvent-free, though they contain about the same amount of binder.

In traditional latex paint, globs of binder and particles of pigment are suspended in water. As the water evaporates, the dries and the solvent-softened binder globs become oval shaped. When the water has completely evaporated, the globs of binder are coalesced, and the remaining solvent evaporates. Solvent-free latex has soft binders. They coalesce without solvent.

Both types of paint form a high-quality, long-lasting film, but the solvent-free variety is preferable if you’re sensitive to chemicals.

Paint manufacturers make a point of stressing that their product meets or exceeds federal standards for volatile organic compounds (VOCs).

Most high-quality latex paints meet this requirement and therefore are “low odor” or “low VOC” by nature. But this does not mean they are solvent-free or as close to it as possible.