HEMPEL’S FOULING DEFENCE SYSTEMS
A game changer for the New Zealand Marine Industry
Hempel continues to invest in its R&D ever since it was first established in 1915 in Denmark. Today, Hempel is highly respected in the world of Marine coatings, and has more than 15 R&D centres across the globe. In New Zealand, Hempel has optimised the assortment of antifoulings for the pleasure boat and commercial boat market, ensuring a good mix of both value for money products, and higher end top performance systems.
A closer look at the antifouling range available from Hempel in the New Zealand market reveals an assortment of patented technologies which give it a real point of difference over its competitors when it comes to controlling biofouling.
All antifoulings are designed to absorb water, as this seawater interaction with the biocide forms part of the working mechanism. However, previous generation binders, particularly seen in older ablative technologies, become mechanically weaker as they absorb water, and affect the strength of the overall coating system. This in turn leads to poorer performance over time.
Hempel has patented the addition of an inorganic microfibre to their antifoulings, and this advancement has enabled their systems to still absorb water, but remain mechanically strong over their lifetime. This means more effective and efficient polishing, better performance, but also a reduced leached layer (spent antifouling matrix) enabling the biocide release to always take place closer to the surface. During maintenance, this also means new antifouling is applied on top of the existing coatings, rather than being absorbed into the matrix. The added benefit of this reinforcement is a smoother finish, which particularly for higher speed vessels or racing yachts, provides less resistance and drag through the water.
Another key point of difference seen in the higher end antifouling range from Hempel is the addition of Nano Capsule Technology. The Nano Capsules enclose a high end biocide mix, and have a hydrophilic outer layer which dissolves in seawater, exposing the internal biocide mix at a more controlled, even rate. This interaction generates a more consistent biocide release rate, and results in much more controlled polishing and fouling control action. Because this release rate is less susceptible to changes in speed or activity, as it is activated by seawater absorption, polishing rates are more consistent and overall performance is improved over conventional self-polishing and ablative technologies, almost independent of speed or activity. As an end user, this also can mean less antifouling is required to often achieve a better performance than other products in the marketplace.
A critical aspect is of course also the biocide package used in the antifouling assortment. Hempel has tested and improved these systems over many years and has tested them in the most aggressive fouling waters in the world.
Today in New Zealand, there are still a number of ablative products still seen in the marketplace. Hempel has moved away from ablative technology in most markets today, in favour of the more controlled self-polishing systems. Traditionally, ablative technology antifoulings released biocide at a less controlled rate and leave higher leached layers (spent antifouling matrix), and require more Cloud 9 maintenance during slipping or docking. This results in costly maintenance, and can affect stability of future antifouling coatings if overcoated. It is often seen at slipping, that the coating ‘disappears’ into the previous coat as the new coating fills the void left behind from the previous system. This coating is effectively lost and will never be exposed at the surface, so in essence will not be utilised.
Alongside their world leading antifouling assortment, Hempel also leads the market in biocide free hydrogel silicone fouling release technology for underwater hulls, which most pleasure boat owners know from the earlier generation products aimed at the commercial market, contains no or very little biocide nor polishing properties, and works on the premise of low surface tension. Organisms have difficulty in attaching themselves to the coating, and those that do settle, are unable to remain attached as the vessel gets underway again. Globally, more and more commercial and pleasure vessel owners are turning to lower biocide or biocide free systems and Hempel has been pioneering coatings in this marketplace for more than 20 years.
In summary, the combination of high performance antifoulings now available from Hempel in their Olympic, Globic NCT, Aluxtra NCT systems and their world leading advanced HEMPASIL range of products, steps up the fouling control game in New Zealand.