Polyurethane Paints & Coatings

Two-pack polyurethane paints are used almost exclusively as topcoats as they offer excellent UV resistance as well as providing a high gloss and enhanced durability. These characteristic come from the fact that as well as physically drying like traditional single pack paints, the two components (a base and a curing agent) under go an irreversible chemical reaction. This chemical reaction relies on the two components being combined together in the right quantities so it is extremely important to adhere to the correct mixing ratios.

One of the disadvantages of two-pack polyurethane paints is that they cannot be applied over an existing single pack coating. This is because they contain relatively aggressive solvents that can "attack" single pack paint causing it to shrivel and peal.

Polyurethane paints also tend to become tacky very quickly due to solvent leaving the paint surface. This will be especially true if applying in hot, dry or windy conditions. It may be necessary to thin the paint (with the correct solvent) in order to increase the working time.

The best results come when application is by conventional airspray, however a near spray like result can be achieved by using a brush and roller. One way of achieving this result by hand is to use what is know as the "tip and roll" technique which involves applying the paint with a foam roller and then removing any roller marks with the tip of a brush.

Jotun's range of polyurethane topcoats are called Hardtop. There are several products in the Hardtop Range all of which have slightly different properties; for instance they offer different levels of gloss, flexibility, hardness and ease of application. Furthr information can be found on the individual product pages which are located here.

If you have any questions about Jotun's range of polyurethane marine paints then please contact us.