Produced through the distillation of tar from wood or coal, creosote is used to protect wood against termites, fungi, mites and other pests. Allowed only for industrial applications, creosote is commonly used to treat railway sleepers and other outdoor installations such as utility poles.
Creosote contains polyaromatic hydrocarbons, including benzo(a)pyrene, which is classified by the International Agency for Research on Cancer as a Group 1 carcinogen. Creosote-treated wood can leach chemicals that may spread through the soil, contaminate groundwater and be absorbed by plants and animals.
“As there is widespread expectation that creosote will eventually be banned, wood treatment producers have started to work on alternatives. One such solution is based on copper, oil and bitumen,” says Ghislain de Quatrebarbes, Nynas Market Manager Chemical Industry.
Thanks to their great solvent power, Nynas NYTEX® grades are an attractive choice for formulators. The naphthenic character of these heavy black oils facilitates absorption during the wood impregnation process and provides a water-repellent effect, protecting the wood from degradation.
“NYTEX 441 and NYTEX 4700 are high–viscosity, ready-made bitumen-oil blends that provide superior hydrophobic properties and serve as carriers of the active components in industrial wood protection.”
Copper naphthenate is an active ingredient used against fungal rot, decay, termites and wood-boring insects. The bitumen acts as a binder, has a water-repellent function and gives the dark pigmentation that is desirable in industrial wood treatment.
“The NYTEX range is cost-efficient, HSE-compliant and offers easy handling with transportation possible at ambient temperatures,” concludes Ghislain de Quatrebarbes.