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We speak to George Hand of Grapefruit Coatings about RENOLIT Dolphin S

by Mark Jardine 25 May 2018 19:30 NZST
RENOLIT Dolphin S Hull Wrap © Grapefruit Coatings

We spoke to George Hand of Grapefruit Coatings to find out more about RENOLIT Dolphin S, the film-applied alternative to antifoul paint.

Mark Jardine: First of all, can you give us an introduction as to what RENOLIT Dolphin S is?

George Hand: Instead of a biocidal related antifouling, it's what we call a foul-release coating: a highly dense Fluro-Silicone layer which makes it very difficult for any barnacles, algae, any sort of bio activity to cling on to. Essentially it's a very low surface-energy surface and is inherently hydrophobic.

Travelling at speeds below seven knots you might see a tiny bit of growth forming, but the organic matter that is on there will only cling very gently. You can use a washing up sponge or soft cloth and it will just wipe away incredibly easy. When you get a flow of over seven knots, the sheer action of the water against the hull will self-clean and take away any of that organic matter.

Here's a video showing just how easy the hull is to clean after a quick jet wash:

Mark: So it is creating a surface which marine life can't bond to?

George: That's exactly how it works. Instead of releasing chemical agents and toxic biocides that kill the matter and are eroded away from the resin paint, leach into the sea bed and cause all sorts of issues through the marine environment, this just allows them to carry on leading a happy little life and just making the general marine environment much nicer for us to be in.

Mark: Grapefruit Graphics has always been associated with vinyl wraps on boats, and making boats look incredible with corporate sponsorship and any kind of graphics that an owner might want. Why can't RENOLIT Dolphin S just be painted straight onto a hull?

George: Unfortunately, it is incredibly difficult to get this paint to stick to the hull without very good surface preparation and all sorts of constrained environmental controls to apply it in. You have to allow the fluro-silicone to be sprayed in the right format to adhere to the hull properly. So what Renolit do is cast the material in a factory under controlled conditions to make sure it bonds to a primer layer on this film with a high-strength acrylic adhesive, which we can then apply without any tenting or any special breathing apparatus and stick it straight into the hull.

Mark: So effectively, Grapefruit Coatings' expertise, with what you have done with vinyl on boats, has got the paint manufacturers out of a problem - because it's your expertise that allows vinyl to be wrapped on to a hull as otherwise they just couldn't get it onto a boat without the boat coming into a factory?

George: That is exactly it. The technology has come over from the shipping industry, where eliminating bio-fouling is of great interest of the commercial shipping industry, as even a small amount of growth can create a great deal of drag and therefore increased fuel costs. They apply it in spray formation on vessels which are hundreds of meters long and it is not cost effective for the man hours to wrap the hulls. They can put the ship into a contained environment and spray it on, whereas our suppliers - Renolit, who supply us with our film, have combined fluro-silicone polymer with adhesive film to provide this safe, inert product, and on smaller vessels it is more cost effective to wrap the hull in sections and then butt-up and use a paint formulation to seal in the seams.

Mark: What's the environmental impact of this? If it is a product which just creates a difficult surface to bond to, rather than something which disperses and tries to kill the marine organisms, I presume this is far more environmentally friendly?

George: Incredibly so. The benefits are year-on-year; you don't have to take the boat out of the water. If you go over seven knots then the hull should be self-cleaning anyway, but you don't have to sand it back and reapply fresh coat each year. You don't have to sand off that toxic material that will be leaching back into the water systems.

Although much damage has already been done from 10-15 years ago, when Tributyltin additives were taken away from antifoul because of the damage they did to the environment, and tighter and tighter legislation has removed a lot more of the biocides, making antifouling paints less and less effective. You see people getting increasingly frustrated and searching for alternatives, hence all the attention we are getting for RENOLIT Dolphin S.

Mark: What surface preparation is needed for you to wrap a boat in RENOLIT Dolphin S?

George: The hull surface would need to be free of Osmosis and any repairs or treatments carried out. We would then need any existing anti-foul paint removed and the surface sealed with a single coat of epoxy primer such as International Primocon to neutralise the surface. Although the film is impermeable and the seams are sealed, we recommend that if the hull has had a history of Osmosis issues or the customer wants to ensure complete Osmosis protection then an anti-osmosis treatment should be carried out prior to the epoxy primer stage.

We can bond to steel and aluminium as well - so long as the surface that we are bonding to is sealed, of reasonable quality, and free from self-polishing paint, it would bond to it and be fine for application.

Mark: So this is something where the Grapefruit Coatings team will just come along, apply the RENOLIT Dolphin S film to the hull, and then head off?

George: Yes, that is currently how we are going to operate, but what we are looking to do in the future is train up trusted boat yards around the country, whereby we can supply them with material and reduce travel costs and fuel emissions. We care about the environment so it will be good to be able to post off the material and have our trusted fitters all around the country apply the film.

Mark: What do you see this doing to the antifoul industry? It looks like an industry disrupter?

George: Yes, from the vast amount of attention we have had recently, there is a definite need for it and people are concerned about the environment. We all enjoy going out in our boats at the weekends and we love being on the water. We have all this publicity about plastics in the oceans, which again is a terrible problem, and we now have sea bins which are collecting litter in the marine environment, but one area that people are looking at is antifoul. People hate that toxic material is leaching into the sea beds and causing issues along the food chain. We are seeing these tiny organisms being eaten by larger organisms, which we end up fishing out and eating. From what reaction we have seen it is definitely a disrupter into the antifouling market.

Mark: How long will RENOLIT Dolphin S last on a boat? Do you quote a lifespan for it in the same way that you have with regular antifoul paint?

George: It has an expected lifespan of 5 years, but that is because that is all the data we have at the moment. Being such a new technology, we cannot go around promising they will last for 10 years when we haven't had it testing for 10 years. There is nothing to say it wouldn't last that long as it is not leaching any harmful chemical agents, it is just purely a physical property. There is nothing to say it should wear out - it should prove effective for many years to come.

Mark: It is fantastic to see something like this that can benefit the environment and also benefit our sailing. Thanks very much for your time.

George: Thank you Mark, and thank you for taking the time to talk to us.

Talk to the team at Grapefruit Coatings to find out more...

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