Epoxy Paints & Coatings

Epoxy coatings are used because they offer outstanding chemical and water resistance, are extremely durable and have excellent adhesion to a variety of substrates. They are two-pack paints which mean they consist of two components (a base and a curing agent) which must be mixed together in the right ratios prior to application.

One disadvantage of epoxy based products is that they have a poor resistance to ultra-violet light. In real terms this means that if left in direct sunlight for long periods epoxy products yellow and a white residue will form on the paint surface- a process known as chalking. This is purely a cosmetic issue and does not interfere with the chemistry of the paint, but can easily be avoided by overcoating the epoxy with a suitable topcoat.

As mentioned previously, epoxy products consist of two components that must be mixed together prior to application.

Once the components have been combined they must be applied within a specified time limit- this is known as pot life. Pot life can vary from anything from a couple of minutes to several hours and is heavily dependent on temperature. Once the pot life has been exceeded the epoxy will be too hard and viscous for application to continue.

The best time to recoat epoxy is before the first coat is fully cured (this varies between products), within 48 hours as a general rule. This ensures that the coats will form a chemical bond as well as a physical bond to each other.

An issue to be aware of when applying epoxys are that they are liable to a phenomenon known as "amine blush". This is more common during application by airless spray and occurs when the amine molecules in the epoxy react with moisture and carbon dioxide in the air. The result is a white, waxy coating on the paint surface that hinders adhesion of subsequent coats. Amine blush can be prevented by including an induction period (leaving the combined mixture for a short period before application), and by avoiding application in humid conditions or conditions close to the dew point.

The addition of solvents (also known as thinners) to epoxy products is not strictly necessary however in certain conditions can aid application. Extra solvents will allow the product to flow out better, and will aid penetration into substrates such as wood and concrete.

Jotun has several ranges of epoxy primers all of which provide unrivalled protection and waterproofing. The most popular are the Jotamastic Range and Penguard Range.

If you have any questions regarding Jotun's range of epoxy coatings please contact us.