Jul 28 2006
The new, third generation of coil coating universal primers from BASF Coatings AG is suitable for every type of pre-treatment, is a significant improvement in terms of spreading rate and efficiency, and offers higher eco-efficiency. The first generation still required a chromate-containing pre-treatment. The second was introduced in 1995 and was one of the very early products designed with environmental protection in mind, being the first to enable chromate-free pre-treatment. The now-improved, chromate-free universal primer currently represents the optimum for the present technology standard. The homogeneous white system solution offers the ideal conditions for smooth and textured topcoats and does not just prevent the specter of rust on galvanized steel panels. It sets new records with regard to spreading rate, functionality, adhesion, flexibility and deep-drawability. Corrosion protection values determined using appropriate test methods exceed all previous results. The high-build process is also possible. The improved properties of the paint finishes can be demonstrated with the usual tests, such as the T-bend, tape or salt spray tests. In addition, BASF Coatings stored sample panels in climate chambers at 100 per cent humidity and 40 degrees for periods of many days. At the end of this there was not even a hint of rust. The chromate-free universal primer therefore also passed the weathering test specified by the construction industry, entailing 360 hours in a salt spray chamber, with flying colors. In this test, the permitted maximum corrosion creepback in artificially induced scratches is 2 mm. The new material – with 0 mm corrosion creepback – proved that it really is in a class of its own. The binder system at the heart of this is based on high-molecular polyester resins. BASF Coatings describes this as a combined corrosion protection concept which improves fundamental physical and chemical properties with consequential interdependence by means of new pigments and substances. Compared with the first generation, there has been a significant increase in the solids content and a corresponding reduction in solvents. The pigmentation itself is not only chromate-free, but also free of other heavy metals and carcinogenic substances. Although the environmental aspect in itself is of only marginal interest to the steel-coating companies – they all operate extremely effective after-burners – the peripheral effects (including higher coating speeds with increased quality stability) were probably the deciding factor in creating such strong demand.