Information on Coppercoat
What is Coppercoat?
Coppercoat is a two-part antifoul made up from a combination of specially developed solvent-free, water-based epoxy resin and high purity (99%) copper. Each litre of resin is mixed with 2 kilos of ultra-fine copper (this is the maximum allowed by law) which makes coppercoat the strongest copper based antifouling available.
Is it suitable for my vessel?
Coppercoat can easily withstand high-powered motorboats and racing crafts, it’s also equally effective on commercial vessels and slow-moving leisure vessels, as well as less frequently used boats. (So, in short, yes!)
How does it work?
Science time! Once submerged, sea water attacks the exposed copper powder applied to the hull and causes cuprous oxide (copper(l) oxide) to form. Cuprous Oxide is the inorganic compound with the formula Cu2O, one of the principal oxides of copper. The presence of this deters growth until the surface degrades further to become cupric hydrochloride. This chemical compound takes its form in a yellowish-brown colour, but slowly absorbs moisture to form a blue-green dihydrate. This final form of copper is highly unstable and will be washed away with the movement of the vessel, which in turn removes any growth and slime (self-cleaning!). This process automatically reveals a fresh copper surface beneath the previous layer, whereby the cycle continues. Of course – this cannot last forever; however, it is extremely durable! On average, if the treatment is applied correctly, it can resist weed or barnacle growth for a decade or more! To maintain your coppercoat it’s recommended to lift and scrub once a year to reactivate.
How does it affect the Environment?
Coppercoat is the logical, environmentally friendly, and effective choice for antifouling. With a single biocide (copper powder made in the UK from recycled copper wire), water-based VOC-free epoxy (Volatile Organic Compounds) and minimal leach rate per square metre per day of just 1.4 micrograms. Coppercoat does not pollute the environment or the applicator.
“It’s an environmentally responsible choice to protect our sailing environment.” – Coppercoat
Our Process of Application
The first step in the process of applying Coppercoat to a vessel is to create a blank canvas by stripping away all the antifoul previously applied. This can be removed by slurry-blasting the hull (slurry-blasting is the process of cleaning a surface with a jet of abrasive driven by compressed air or steam). We contract A Groves Fabrication to carry this out for us. This process removes all the layers of antifoul right back to the gelcoat. From here we’re able to lightly sand off the gel coat, fill any pin holes and prepare the surface. All patches of filler must be dried, degreased, and painted with Interprotect before application of Coppercoat.
In total, four layers of Coppercoat are applied to the vessel, these must all be completed within the same day. The second, third and fourth coats should be applied as soon as the previous coat allows (wet-on-tacky). Once all layers are complete you must allow at least 2-3 days for the Coppercoat to cure. The timeframe for this is dependent on the air temperature. Coppercoat will not cure in temperatures below 8°C which is why we typically carry out this job inside our workshop. It’s much easier to control the temperature of an enclosed area rather than relying on the unpredictable weather outside. We must also ensure the fresh Coppercoat does not get wet during the curing period, so rain can be detrimental to the process. An indication that the Coppercoat has cured is to test whether anything comes off when you touch it. After fully cured you can begin the process of lightly sanding the Coppercoat to activate it ready for launch.