Water-dilutable varnishes are definately becoming more popular.
Even problematic surfaces can now be treated with environmental-friendly and efficient two-component varnishes which fulfill the highest professional demands, for example, for plastic surfaces.
Before coating plastic surfaces adequately with water-based two-component varnishes the surface has to be carefully assessed:
The end result depends on the pre-cleaning and on the correct choice of two-component varnish. Surfaces which have not been cleaned thoroughly or are coated with the wrong material can be subject to flaking and therefore cause various complaints. The professional on the building site is mainly confronted with rigid PVC, polyester and polyurethane used as materials for or covering of windows and doors, gutters or balcony parapets. Traditionally solvent-based two-component epoxy-resin priming coats are used as adhesion promoters and then a further appropriate varnish is used for the intermediate and finishing coat.
The new proposition in the building sector is to coat sound construction elements directly with a two-component varnish without a special priming coat. This is possible with our new water-based two-component varnish systems, which is shown by the following renovation of a plastic window frame.
1. Surface treatment:
The plastic surface is first treated with an ammonia-water solution containing a wetting agent or thoroughly cleaned with spiritus to remove grease, then roughened with a non-woven abrasive.
2. Mixing process for the two-component varnish LUCITE®2K-PUR Xtrem Satin:
Now the basic varnish has to be mixed with the hardening agent at a ratio of 9:1. After mixing the components thoroughly the application of the two-component varnish can begin.
In case high-pressure spray application is used then the water for dilution should be added only after the two components, varnish and hardening agent, have been mixed together and formed a homogeneous mass.