New latex paint evaporates least

Anne Berit Bjørken

Studies at NTH/SINTEF have shown that a new generation of water-based paints evaporate organic compounds at a lower rate than traditional types of paint.

Paints and other products can be tested in NTH/SINTEF's new laboratory", says Olav Bjørseth.

"The introduction of water-based paints, i.e. latex paints, has been an important step in the right direction for professional painters. All the same, it turns out that such paints also release a certain amount of solvents to the indoor environment," says Olav Bjørseth, a scientist at ORAL, NTH.

"A number of previous studies had already shown what sort of components evaporate from paint, and how long the evaporation process lasts. But it is only now, when we have harmonized our test procedures and set up a range of test chambers, that we are in a position to carry out standardized tests in Norway," says Bjørseth.

With funding from the Research Council of Norway and other sources NTH/SINTEF is currently studying the evaporation of organic components from four types of paint. The four paints include solvent-based oil paint, standard latex paint, water-based natural paint and a second-generation latex paint which does not contain solvents.

"The new latex paint does extremely well in these tests. The rate of evaporation is much lower than that of the other types, both during the first few days and also later on. This type of paint will be probably be preferable for people who suffer from allergies," says Bjørseth.

New laboratory

During the past year, a test laboratory for paints and similar products has been built up at NTH/SINTEF. In addition to a number of small evaporation chambers a large (12 m3) room for testing evaporation from all sorts of materials has recently been completed.

The new chamber has a brushed steel finish, and it is ventilated with air that contains neither particulate nor organic contaminants. The new laboratory will help manufacturers to develop healthier products, but it will also mean that consumers can obtain better information on health aspects of the products around us.