Polyurethane base coats – Excellent protection for many substrates
During any multi-layer coatings application the first coating to be applied is a base coat which protects the substrate from any humidity or any oxidizing substances and ultimately from corrosion. Polyurethane base coats can be used on many different substrates even though they are mainly used for the coating of metal substrates, such as untreated, phosphatized or galvanized steel panels and aluminum or chromated aluminum.
For these base coats mainly polyester based two-component polyurethane systems are used. They produce good adhesion and provide good corrosion protection.In case a higher chemical resistance and weather resistance are required, the hydroxyl content should be higher.
Moreover it is important to use fast curing systems in order to obtain an efficient coating process. One-component or two-component formulations for low-temperature curing or stoving coatings are the systems of choice.
Depending on required processing needs and property profile waterborne binders and conventional binders, both in one- or two-component formulations can be used.
Selection of products for industrial primers
This is just a small selection of the large product range for primers in plastic applications. Since there are almost limitless industrial applications possible and many different substrates used and because of varying processing characteristics it is essential to discuss the selection of products for each individual application. Get into touch with your regional representative to discuss your individual requirements.
One-component polyurethane raw materials for waterborne primers: Two-component polyurethane raw materials for waterborne primers:
Primers based on waterborne two-component polyurethane technology are characterized by a virtually unlimited flexibility in the choice of binder components and formulations and, as a result, in the quality of corrosion protection properties (up to corrosion protection class C4 medium in accordance with DIN EN ISO 12944). Consequently, these primers stand out in terms of impact strength, achieving above-average performance in stone impact tests and being successfully deployable on non-torsionally-rigid steel substrates.
In terms of productivity too primers based on waterborne two-component polyurethane technology can score, especially as a result of their drying and through-hardening properties, which can be specifically influenced. Rapidly drying ready-for-finishing primers can be easily formulated.
A selection of possible binder combinations for primers is listed in the tables below.