TBT-Free Paint Page 2
|Going... Going... Almost Gone|
Part 2: Either way, these new alternatives are an improvement.
By Capt. Ken Kreisler — April 2003
However, with the word getting out, and as the major paint players will soon no longer be using the stuff, it’s only a matter of time before it will disappear for good and all boat owners will have to use non-TBT paints. So what are your options? Akzo Nobel, parent company of Interlux, has two solutions. The first is Micron 66, a self-polishing copolymer (SPC) bottom paint that the company claims is at least as effective as TBT-based paints. (Copolymers chemically allow the biocides to be released over a controlled period of time.) A typical application can last as long as three years, but because Micron 66 must be applied in just the right amount for it to be effective, it should be applied only by professionals. For the do-it-yourselfer, Micron Extra is available.
Either way, these new alternatives are an improvement. “Traditional antifoulings cannot match the lifetime of a SPC antifouling,” Bob Donat, Interlux’s North American marketing manager, recently told me. “That’s because [with TBT coatings] the amount of biocide released decreases during the coating’s life until there is not enough left to deter fouling,” adds Interlux’s Jim Seidel. Instead, Micron 66 uses a controlled reaction with the salt water that allows a constant release of biocide throughout the product’s lifetime. Moreover, Micron Extra can be used in both fresh and salt water.
The company’s other TBT substitute, Trilux 33, is for aluminum vessels, from pontoon craft to megayachts, as well as for outboards, outdrives, and applications requiring bright colors on any hull material. It is a slow-polishing antifouling featuring Interlux’s Biolux, an added booster technology which, according to Interlux, allows the same level of protection from the first day to the last. Trilux 33 is also available as an aerosol, Trilux Prop & Drive, for easier application to outboards and outdrives.
Pettit also offers a number of TBT-free paints, including Ultima SR, an ablative copolymer, and Trinidad SR, a hard-leaching paint. Hard-leaching paints function by slowly dissolving their water-soluble components, releasing biocide. What’s left is a film that must be sanded off before the boat is primed for another painting. “We stopped using our TBT-based product back in 1989 when the IMO recommendations first appeared,” said John Ludgate, vice president of sales and marketing, during a telephone conversation. “And our TBT aerosols for outboards and outdrives will be gone as of this summer.”
To protect against hard fouling by mussels and barnacles, Ultima SR uses high amounts of cuprous oxide combined with Irgarol, an organic algaecide that kills slime, as boosters. “And because the product is an ablative and has a controlled erosion, this minimizes coating, so the running bottom is kept clean and smooth,” Ludgate says.
This article originally appeared in the March 2003 issue of Power & Motoryacht magazine.