I Can’t Believe It’s Not Coppercoat!

As to how Copercoat works, this is from their website:

Coppercoat is the combination of a specially developed two-pack epoxy resin and 99% pure copper. Each litre of Coppercoat contains 2kg of ultra fine copper powder, the maximum allowed by law. On immersion, sea water attacks the exposed pure copper, causing the formation of cuprous oxide. This highly effective anti-fouling agent deters growth until the surface degrades further to become cupric hydrochloride. This final copper form is highly unstable, and is washed away by the movement of the yacht, thereby removing any accumulating silt or slime. This automatically reveals a fresh copper-rich surface whereby the process recommences.

So there you go, that's how it works. We've had it on our boat for 15 years now, with the original coat being overcoated this year. We recoated as it was getting thin in places. As far as we're concerned the advantage of the stuff is that it is as effective as conventional antifoul (ie after twelve months in the water there will be q coating of slime plus minor growth) but all of that is easily removed with a quick power wash. No scrapping back and reapplying yet more antifoul. Every few years it needs a light sanding to reveal fresh copper and that's it. That's why we use it and why we decided to recoat the boat. No magical eroding resin, just chemical processes involving the suspended copper powder.
 
lukedh said:
So if I took some cheap self-eroding anti-fouling and add my copper to it would that do the trick?
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Unfortunately it would erode away in a lot less than ten years. Probably somewhere between one and three years assuming adding the copper to the antifoul didn't cause it to erode at a different speed.
 
lukedh said:
So if I took some cheap self-eroding anti-fouling and add my copper to it would that do the trick?
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You might find that sourcing copper powder, not some alloy, and of the right size and particle size distribution or even getting a close approximation of size and psd, is neither easy nor cheap, and that the copper expense will be wasted in a cheap ablative AF. Additionally ablative AF are designed to ablate at a specific rate partially determined by the solids loading - to make any impact you will need to seriously load the paint with copper - which (I'm guessing) will increase the ablative rate. So it might work a treat - but not last long.

A better option might be to add copper powder to a, cheap, hard AF. But, as with CC, you still need to ensure you have fresh active copper or it will not work.

I have always thought a pigment grade copper flake would work, it has a high surface area, but to be effective it needs to 'leaf', get all the little plates to lie flat - and I'm not sure that will work with viscous AF - really I have no idea!
 
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Anyone who locks 2 Kg of copper powder into 1 KG of Epoxy resin is wasting the largest part of it.... the only active part of copper powder added to a waterproof epoxy resin would be any tiny exposed surfaces of the copper particles closest to the surface of the resin layer. (even this is doubtful if the copper has been mixed in well as the copper will be coated with the resin)
Yes agreed any tiny amount of copper that may be exposed after application may have an affect, the exposed amount will of course govern the degree of that effect.
Any abrasion to the hard waterproof layer of Epoxy will of course expose more tiny copper particles to the surface of the water and will increase that effect .
The statement that 'as the highly unstable copper washes away and automatically revealing fresh copper is fanciful. The only thing that will be left as the copper washes away would be tiny voids where the copper particle had been, the rest of the active and useful copper would not be automatically exposed.
Lets be clear .... hard abrasion resistant waterproof epoxy resin is not going to erode away itself to any useful degree. ( perhaps in a few thousand years of being washed by water an reduction of the Epoxy may be measured.
So the only way to expose the active part ( the copper powder) is to abrade the epoxy resin yourself.
It seems that these copper epoxy resin systems are trying to imitate the washing and self eroding quality that an antifoul resin has.
Perhaps if not such a tough and waterproof resin was used it would save all the hardship of having to sand the underside of a yacht to expose the copper trapped within the Epoxy.
Antifouling is of course in a very basic description a water soluble resin with copper added and other biocides that fight slime as well, oh and not forgetting a pigment to make it look good.
The main point of this is that antifouling clearly does erode and will of course quite efficiently expose fresh copper and biocide to the water to fight slime as well as hard shells.
The efficiency of this erosion is of course between the different brands, some are quick eroding and may need extra added to last the chosen time and may not be any good on a fast boat, others are harder and better on fast boats but may not be as effective on slow boats.
Making a standard yacht antifouling last more than 1.5 2 years is the hardest part .
They need to erode to work efficiently and to expose the good stuff which means that a long term antifouling would need extra thickness.
Extra thickness is not always going to wash efficiently through the whole layer, most of them don't wash or erode as well as we are led to believe and most will build up an insulating layer on the surface which significantly reduces the effectiveness after 1.5 -2 years.
This insulating top layer can be removed and the good stuff underneath will continue to work well but most boat owners don't like to remove what they regard as their expensive antifouling. (which its not of course its a dead inactive layer on the surface)
 
duncan99210 said:
As to how Copercoat works, this is from their website:

Coppercoat is the combination of a specially developed two-pack epoxy resin and 99% pure copper. Each litre of Coppercoat contains 2kg of ultra fine copper powder, the maximum allowed by law. On immersion, sea water attacks the exposed pure copper, causing the formation of cuprous oxide. This highly effective anti-fouling agent deters growth until the surface degrades further to become cupric hydrochloride. This final copper form is highly unstable, and is washed away by the movement of the yacht, thereby removing any accumulating silt or slime. This automatically reveals a fresh copper-rich surface whereby the process recommences.

So there you go, that's how it works. We've had it on our boat for 15 years now, with the original coat being overcoated this year. We recoated as it was getting thin in places. As far as we're concerned the advantage of the stuff is that it is as effective as conventional antifoul (ie after twelve months in the water there will be q coating of slime plus minor growth) but all of that is easily removed with a quick power wash. No scrapping back and reapplying yet more antifoul. Every few years it needs a light sanding to reveal fresh copper and that's it. That's why we use it and why we decided to recoat the boat. No magical eroding resin, just chemical processes involving the suspended copper powder.
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Hmm, I spent a small fortune getting our boat coppercoated early last year. I usually dive to check that all's ok but didn't go under to look last year. We were hauled out in June this year and the hull was covered in a thick brown weed, about 2cm long, which came off easily either by rubbing it or, in our case, pressure washing it. No sign of any barnacles or any other hard growth.

I dived last week, having been back in the water about 3.5 months, to find a similar amount of weed. That was rather disappointing after a relatively short period. However after 2 underwater cleaning sessions most of it has now gone (good exercise!), again no sign of any barnacles. Most people tell me coppercoat improves with the passage of time, I certainly hope that's true!

My conclusion is that coppercaot seems excellent at preventing hard growth but so far disappointing with weed, although cleaning it is relatively easy, it comes off with a simple wipe of the hand, but it does take time to clean a 48' hull underwater!! And those that say it the weed will be washed away when the boat moves haven't come across the weed found in the River Dart!
 
RichardS said:
Unfortunately your first point about no epoxy resins being water soluble is incorrect so everything that follows on from that is also incorrect. Sorry :)

Richard
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Sticky Stuff said:
Anyone who locks 2 Kg of copper powder into 1 KG of Epoxy resin is wasting the largest part of it.... the only active part of copper powder added to a waterproof epoxy resin would be any tiny exposed surfaces of the copper particles closest to the surface of the resin layer. (even this is doubtful if the copper has been mixed in well as the copper will be coated with the resin)
Yes agreed any tiny amount of copper that may be exposed after application may have an affect, the exposed amount will of course govern the degree of that effect.
Any abrasion to the hard waterproof layer of Epoxy will of course expose more tiny copper particles to the surface of the water and will increase that effect .
The statement that 'as the highly unstable copper washes away and automatically revealing fresh copper is fanciful. The only thing that will be left as the copper washes away would be tiny voids where the copper particle had been, the rest of the active and useful copper would not be automatically exposed.
Lets be clear .... hard abrasion resistant waterproof epoxy resin is not going to erode away itself to any useful degree. ( perhaps in a few thousand years of being washed by water an reduction of the Epoxy may be measured.
So the only way to expose the active part ( the copper powder) is to abrade the epoxy resin yourself.
It seems that these copper epoxy resin systems are trying to imitate the washing and self eroding quality that an antifoul resin has.
Perhaps if not such a tough and waterproof resin was used it would save all the hardship of having to sand the underside of a yacht to expose the copper trapped within the Epoxy.
Antifouling is of course in a very basic description a water soluble resin with copper added and other biocides that fight slime as well, oh and not forgetting a pigment to make it look good.
The main point of this is that antifouling clearly does erode and will of course quite efficiently expose fresh copper and biocide to the water to fight slime as well as hard shells.
The efficiency of this erosion is of course between the different brands, some are quick eroding and may need extra added to last the chosen time and may not be any good on a fast boat, others are harder and better on fast boats but may not be as effective on slow boats.
Making a standard yacht antifouling last more than 1.5 2 years is the hardest part .
They need to erode to work efficiently and to expose the good stuff which means that a long term antifouling would need extra thickness.
Extra thickness is not always going to wash efficiently through the whole layer, most of them don't wash or erode as well as we are led to believe and most will build up an insulating layer on the surface which significantly reduces the effectiveness after 1.5 -2 years.
This insulating top layer can be removed and the good stuff underneath will continue to work well but most boat owners don't like to remove what they regard as their expensive antifouling. (which its not of course its a dead inactive layer on the surface)
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Errrrr .... Sticky, you are spending a lot of time typing posts which are based on your complete misunderstanding of how water-soluble resins like Coppercoat actually work. :rolleyes:

Richard
 
I would be very happy to agree if any of the copper system makers actually state their epoxy resin is water soluble to any useful degree !

As yet I have only ever statements that it is water based which is an entirely different thing.

Your car may have a waterbased paint does that make it water soluble no of course not !
 
Sticky Stuff said:
I would be very happy to agree if any of the copper system makers actually state their epoxy resin is water soluble to any useful degree !

As yet I have only ever statements that it is water based which is an entirely different thing.

Your car may have a waterbased paint does that make it water soluble no of course not !
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From the Coppercoat website:

The life of Coppercoat depends on a variety of factors such as water temperature and salinity. However, typically in Northern Europe one should expect effective performance for at least 10 years, whereas in the Caribbean, 8 to 10 years would be more normal. Many of the first boats treated in 1991 are still performing well after more than 20 years! With an average thickness of 250 microns of Coppercoat being applied in a treatment, and a typical corrosion rate of less than 5 microns per year, it is easy to appreciate how this coating offers such long lasting and effective protection.

If the coating is eroding at the rate suggested and that rate increases when the water is warmer ....... I'll leave you to draw your own conclusions. :)

Richard
 
Any layer of well cured Epoxy has a very good chance of lasting 1000 years in water it not touched !!
How long it lasts will depend on how many times it is sanded to try to expose fresh copper each time.
The real question is how well does it works to reduce shell, weed and Slime growth over that time in comparison to an antifouling.
There are so many different results and opinions with this type of system and the main differentiating factor is how much exposed copper each example has.
Some may have more exposed copper simply due to application technique, the roller type used to apply it, how long was it applied after mixing (applying it when it is thickening will change the way the copper is suspended in the resin), the temperature of the product, the temperature of the air and the temperature of the surface it is applied to will all also make a difference to the resin viscosity and in turn the way the copper is suspended in the resin.
Anyone with what they regard as a good product will have a higher concentration of the copper near the surface and exposed to the water, this could last as well as the exposed copper will take time to erode( having said that in most cases slime and weed will continue to build up due to the lack of any slime and weed fighting biocides in the formula) Anyone with a poor performing product will have a much higher resin content on the surface with less exposed copper exposed. (Sanding will of course expose the trapped copper)
In reality the Idea of these systems is a good one, in principle they are trying to do the same thing as an antifouling paint ie keep the good active components exposed to the water however they have chosen Epoxy as the base resin (The Binder paint people call it) and this is a non soluble resin.
Perhaps if they added Copper to a known soluble resin they could keep the active copper exposed rather than having to sand it.
Oh hang on then it would be an antifoul !
 
Sticky Stuff said:
Any layer of well cured Epoxy has a very good chance of lasting 1000 years in water it not touched !!
How long it lasts will depend on how many times it is sanded to try to expose fresh copper each time.
Perhaps if they added Copper to a known soluble resin they could keep the active copper exposed rather than having to sand it.
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If I continue with this debate I'll begin to sound like some kind of AMC PR man! :)

I'll leave it to Ewan from AMC to take up the debate if he so wishes.

Richard
 
Oh dear! There is no such thing as a water soluble epoxy - once it is cured. The two components of base resin and curing agent use water as a solvent in a water based product. When they are mixed together a chemical reaction takes place, usually described as curing, and the water is displaced to evaporate as per the solvent in most coatings. Cured epoxy is not a convertible material. In other words it cannot be dissolved in its own solvent once cured. The limit to its life will be the quality of surface preparation and application along with the abrasion resistance of its formulation
 
Pasarell said:
Oh dear! There is no such thing as a water soluble epoxy - once it is cured. The two components of base resin and curing agent use water as a solvent in a water based product. When they are mixed together a chemical reaction takes place, usually described as curing, and the water is displaced to evaporate as per the solvent in most coatings. Cured epoxy is not a convertible material. In other words it cannot be dissolved in its own solvent once cured. The limit to its life will be the quality of surface preparation and application along with the abrasion resistance of its formulation
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Oh dear indeed.

Search this page: https://en.wikipedia.org/wiki/Epoxy for the term "water soluble". :)

Richard
 
I am not trying to give this type of product to much of a hard time I just think people should look at the facts first.
Perhaps there is an effect against shell growth if the copper is exposed, what I do not believe is that they get continual erosion with an Epoxy as the base resin.
So if people don't mind a good sand underneath their boats whenever the copper needs to be exposed they may well get some degree of protection against shell growth.
Lets hear from the makers !!
Is their resin water soluble ? If not could they explain how the copper entrapped in their resin is continually exposed to enable an antifoul effect ?
The Copper coat Datasheet says this .......'With the epoxy being water miscible until cured, protect the hull from rain for 48 hours.'
The dictionary definition of 'miscible' being:
mis-ci-ble
Capable of being mixed:

So basically after 48 hours water has no effect on the cured product.
The only erosion that can then take place is the exposed copper (if any is exposed without an good sand)

Perhaps Ewan from AMC can explain their datasheet and how the Epoxy erodes to any useable extent to expose new copper.
 
Sticky Stuff said:
I am not trying to give this type of product to much of a hard time I just think people should look at the facts first.
Perhaps there is an effect against shell growth if the copper is exposed, what I do not believe is that they get continual erosion with an Epoxy as the base resin.
So if people don't mind a good sand underneath their boats whenever the copper needs to be exposed they may well get some degree of protection against shell growth.
Lets hear from the makers !!
Is their resin water soluble ? If not could they explain how the copper entrapped in their resin is continually exposed to enable an antifoul effect ?
The Copper coat Datasheet says this .......'With the epoxy being water miscible until cured, protect the hull from rain for 48 hours.'
The dictionary definition of 'miscible' being:
mis-ci-ble
Capable of being mixed:

So basically after 48 hours water has no effect on the cured product.
The only erosion that can then take place is the exposed copper (if any is exposed without an good sand)

Perhaps Ewan from AMC can explain their datasheet and how the Epoxy erodes to any useable extent to expose new copper.
Click to expand...

Perhaps we should note that other people with long-term (10+ years) experience of Coppercoat have had to re-coat their hulls because the coating had got too thin. Maybe it doesn't dissolve; perhaps it is because the erosion of copper grains causes the intervening epoxy to fragment and erode, which seems plausible to me. But whatever the mechanism, the observed fact is that it thins with age.
 
AntarcticPilot said:
Perhaps we should note that other people with long-term (10+ years) experience of Coppercoat have had to re-coat their hulls because the coating had got too thin. Maybe it doesn't dissolve; perhaps it is because the erosion of copper grains causes the intervening epoxy to fragment and erode, which seems plausible to me. But whatever the mechanism, the observed fact is that it thins with age.
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I was thinking along the same lines. The copper may be encapsulated in epoxy, but clearly that doesn't isolate it from reacting (hence the greenness, of which there are degrees). Epoxy is not completely impermeable, after all. Perhaps the copper reacts and 'blows' off the epoxy...I really don't know, but would be interested in AMC's explanation.
 
macd said:
I was thinking along the same lines. The copper may be encapsulated in epoxy, but clearly that doesn't isolate it from reacting (hence the greenness, of which there are degrees). Epoxy is not completely impermeable, after all. Perhaps the copper reacts and 'blows' off the epoxy...I really don't know, but would be interested in AMC's explanation.
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You have hit the nail on the head here Mac. The epoxy used in Coppercoat is not completely impermeable and will not retain its structure and integrity for the "1000 years" mentioned in some posts. The epoxy slowly breaks down, as do the copper particles. Hence an application of Coppercoat thins over time, as experienced by our clients. Obviously the rate of wear is far less than is the case with an eroding anti-foul paint, hence the longer lifespan. By normal standards the coating would be deemed non-eroding, but of course, it does erode slightly/slowly.

For the vast majority of the 50,000 or so boats now using Coppercoat, the natural wear rate is sufficient to provide a satisfactory level of anti-fouling performance (as experienced by Twister-Ken of this thread, as but one example). But for a few, giving the surface a light burnish every few years (using 600 grade wet-and-dry or similar) to expose even more copper is beneficial.

Interestingly if you go back 25 years or so, there was a system from Scott Bader (Crystic Copperclad) that consisted of adding copper powder to the polyester gel-coat of a new build yacht, at the time of lay-up. The problem with this was that the polyester gel-coat did not usually break down sufficiently quickly to provide satisfactory performance, so the surface had to be manually abraded very regularly. Of course, most people found this inconvenient and the idea was soon dropped. What we did was to work on this idea, change the carrier to more a suitable (i.e. structurally weaker) resin and make it available for retrospective fitment. I can't instantly recall the exact timings, but seem to remember Crystic Coppercoat being discontinued relatively soon after the release of Coppercoat.
 
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