NEWS for the Plastic and Rubber Industry

 

Covestro Shwocases New Water-Based PU Technology at the European Coatings Show 2019 in Nuremberg

  • Covestro supports switch to water-based polyurethane coatings for wood and furniture
  • Fast hardener enables quick drying and performance similar to solvent-based systems

Covestro announces its water-based PU technology for coating applications. The new technolgy enables to switch to lower content of volatile organic compounds (VOC).

Covestro will showcase its new Bayhydur® quix 306-70 at the European Coatings Show 2019 in Nuremberg. This new hardener makes it possible for the first time to formulate water-based, two-component wood coatings of the highest quality that have drying properties similar to solvent-based systems, but cause less VOC emissions.

Drying up to 60 percent faster "Water-based wood coatings that are based on the new hardener and selected polyol components achieve a sand dry after just 35 minutes, and therefore must no longer be protected from dust. In less than two hours, T4 drying time is achieved, meaning the film is fully dried," says Dr. Eva Tejada, wood coatings expert in the Coatings, Adhesives, Specialties segment at Covestro. That means a reduction of the drying time by up to 60 percent over standard water-based PU systems. The pot life is quite unaffected by this: depending on the formulation, the coating can be processed for more than 7 hours after mixing in the components.

Eva Tejada will present a detailed properties profile of the new hardener at the ECS Conference (on March 19, from 2:00 p.m.) as well as at a product presentation on March 20, from 12.10 p.m. Good resistance to chemicals and UV radiation

Water-based wood coatings based on Bayhydur® quix 306-70 have similar chemical-resistance properties to solvent-based systems in the same quality category. Extensive comparison tests, in which coffee, red wine, mustard, ethanol or water came into contact with the coatings, are proof of this. In terms of appearance, no compromises must be made either: water-based clear coatings with the new hardener shine just as much as mainstream solvent-based PU wood coatings.

From a chemical perspective, the new hardener is an anionic modified isocyanate, comprising both an aromatic and an aliphatic part. Despite the aromatic part, white-pigmented wood coatings based on Bayhydur® quix 306-70 do not turn yellow faster than standard solvent-based systems when exposed to UV light or heat. Overall, Bayhydur® quix 306-70 enables coatings manufacturers to formulate dual-component wood coatings with a VOC content below 100 g per liter that are just as effective and efficient as comparable solvent-based systems.

For more information, please visit www.covestro.com