Search Results

Two component urethane coatings are noted for their ability to low temperature cure. As a class, once fully cured, they are not generally noted for recoatability without surface treatment. However, with some understanding of the cure mechanism, attention to formulation variables and control of the cure process conditions, the recoatability window of 2K urethanes can sometimes be significantly widened. The role of humidity in the cure process is perhaps of more significance than many people once thought. The benefit of introduction of humidity into the “bake” oven during winter dry conditions is clearly demonstrated in a case history for one system for a major 2K urethane finisher of large exterior plastic components.

RIM is losing its competitive position for automotive facias and claddings to lower cost polyolefin substrates. One method of cost reduction without sacrificing appearance or long term durability is to use primerless polyurethane coatings. This paper will address the technical considerations and economics in support of this alternative.

The use of polyurethane coatings applied directly to automotive plastics as exterior topcoats is growing rapidly. Their generally high performance characteristics coupled with unique ability to rapidly cure at low temperatures is being recognized. However, also being recognized, is the need to thoroughly understand the physics and chemistry of both the plastic and the coating for these applications to be fully succesful.