Marine coatings improve as needs demand

Having the correct coating on a ship’s hull can have a significant impact on vessel performance.
Having the correct coating on a ship’s hull can have a significant impact on vessel performance.
Having the correct coating on a ship’s hull can have a significant impact on vessel performance.

According to business analytics firm, Markets and Markets, the global marine coatings market is worth nearly $4 billion globally and has been growing consistently at nearly 4 percent annually due to the increased number of vessels, large and small, being built around the world.

But it’s not just growth measured financially, there are also new and emerging product capabilities. 

In a nod to the popular Harry Potter series of books and films, Sheu-Jane Gallagher, Ph.D., co-founder of Repela Tech, a spinoff from Wayne State University, describes her company’s antifouling coating technology, as being like a `Cloak of Invisibility’ because it makes a hull effectively disappear from a biological standpoint. 

The coating is hydrophilic – ‘water loving’ – a characteristic that, in effect, creates a denser layer of water adjacent to the surface. That, in turn, acts as a protective barrier, without altering any hydrodynamic qualities, she explained.

Living things “are looking for a hard surface to settle on and when they encounter our coating all they come in contact with is a denser layer of liquid,” she said. 

Dr. Gallagher partnered with Zhiqiang Cao, Ph.D., professor of chemical engineering and materials science at Wayne State’s College of Engineering, and Edward Kim, a former mentor-in-residence at the university and an angel investor to co-found Repela Tech, which has attracted government grants and seed funding to help it on its way.

Of course, beyond its ability to protect hulls effectively, Gallagher notes that unlike traditional hull protective coatings, which release copper and other biocides into the water, Repela Tech has no such environmental impact.

“We are benchmarking against silicone coatings and plan to be in the market in 2024, initially on recreational boats,” she explains. “We are a startup in a market dominated by a lot of large, multinational players so the ship market is in the future,” she says, adding that, although in the latter stages of its development stage, the company is doing some full-scale testing on recreational boats and test patches on other larger vessels.

A constant growth mode
Startups like Repela Tech are a traditional source of innovation in many industries but, of course, at the same time, the larger, more established players in marine coatings aren’t resting on their laurels.  

Matt Heffernan is Commercial-Marine Business Manager for North America at Sherwin-Williams, one of the world’s leading coating manufacturers with a global footprint and significant supply chain and technical resources.

“We were founded more than 157 years ago, and we are still in a growth mode,” he said. “Indeed, during the pandemic we were making acquisitions and strategic purchases, and strengthening vendor partnerships, which allowed us to expand our product offerings.”

Compound work at one of Sherman-Williams 146 labs development labs.
Compound work at one of Sherman-Williams 146 labs development labs.

One of them is the company’s patented SeaGuard One-Step Decking System,“which is emerging for us, though not entirely new to the market,” he said.  

With SeaGuard Decking, the focus is on internal shipboard spaces, Heffernan said, noting that for shipbuilders, owners, and charterers, there are not many options available. 

One of the benefits of working with Sherwin-Williams, said Heffernan, is the company’s broad product offering “so when you are doing a project in a drydock, if we are doing your hull or topside, you can also use us for interior spaces; you don’t have to go to a different vendor streamlining logistics, purchasing, and inventory management.”

“A lot of the issues are regulations and approvals. So, the question is, do you have SOLAS approvals and IMO approvals, which we do have,” he said, adding that the product is qualified to MIL specifications but is widely used in commercial applications, as well, and is not especially compounded for different customers. 

According to company literature, SeaGuard One-Step System is a “durable, ultra-high-solids, low-odor system with a quartz-like finish.” It is qualified to U.S. Navy decking specifications and comes in eight stock colors with custom blends also available. SeaGuard Cosmetic Polymeric Epoxy Decking “can be used in both wet and dry spaces and can be applied on properly prepared surfaces including steel, aluminum, sealed underlayment and properly cured primers.”

Heffernan explains that the features of the product depend on a combination of pure adhesion capabilities and built-in chemistry. The product cures in multiple ways, secured by chemical reaction. Two components are mixed together and react, which speeds up the process and forces a harder cure that can even be used for immersion grade applications.

“One of the main reasons customers adopt this particular coating is hygienic,” he said. “In contrast to typical decking and flooring systems, the bulkhead and deck have hard edges and in places like the head or galley, those edges can trap dirt, moisture, and bacteria.” 

SeaGuard Decking can be used to create a cove to become a seamless transition up the bulkhead that can extend for three to six inches. “You no longer have that hard edge where bacteria can grow and water can infiltrate under flooring,” potentially leading to corrosion. “This approach is seamless, and water can’t get underneath,” he said. 

According to Heffernan, a stated goal for the company’s entire marine product line is the continuing effort to lower solvent content and lower the level of volatile organic compounds (VOCs). “This helps both the environment and aids the shipyard in staying under its annual VOC emission cap,” said Heffernan. “We see that as critical as regulatory bodies like the EPA continue to tighten VOC regulations.” 

“The question is always, how do we get ahead of requirements and also become the leader in this space,” he said. adding that spurring that forward thinking “starts with defining the minimum goal and then looking at how to achieve and exceed the goal and provide successful product applications.”

When regulations mandate that a product that’s been a staple of your business for decades needs to be modified or reformulated, there are a number of things that require consideration – for example, when a formula is changed it may well have a negative chemical reaction with the surface to which it is applied.  

“It can be like Whac-A-Mole,” said Heffernan. “So, you have to be very thorough in formulating and that takes time and money and dedicated research and development to assure good results.”

The goal, he said, “is to have products that meet every VOC requirement across the country,” he said pointing to the work being done to meet the extremely stringent regulations in California, the U.S. Northeast, and the Gulf area that “are driving the process. It can be challenging. But when you are prepared and have the needed resources, you can engage with those opportunities.” 

Continuing evolution
Another larger company perspective is provided by Jeremy Pasatta, Chief Operating Officer at Advanced Polymer Coatings Inc. (APC) where the current focus is on developing the advanced coatings – its polymer-modified epoxy ChemLINE and MarineLINE products, for example – that are used  to line liquid cargo tanks. 

Similar to that of Sherwin Williams, the company’s story is of continued evolution. “What we pride ourselves on is really good chemical resistance and low maintenance costs” which also means easy turnaround between cargoes, he said, contrasting the company’s products with the competition, primarily providers of traditional epoxy liners. 

According to Pasatta, Avon, Ohio-headquartered APC saw the need for more versatility in tank lining resulting from the more rapid pace of liquid cargo loading and unloading. Because trading rates are so high, vessel operators want to spend the optimum amount of time moving cargo, not dealing with the potential negative results of changes between different cargoes such as waste oil, fatty acids, and even vegetable oils, “which can become chemically aggressive. We give ship owners the ability to trade as they wish and reduce their downtime.”  

In a typical tank, there is a water layer that can end up carrying some of the acids from the oil, which often makes the bottom layer of a tank very acidic. “Our coating can handle those water-containing oils  and is also resistant to a long list of other chemicals,” said Pasatta.  

The interior of a vessel’s liquid cargo hold after application of one of APC’s polymer-modified epoxy coatings.
The interior of a vessel’s liquid cargo hold after application of one of APC’s polymer-modified epoxy coatings.

“Our product gives operators the confidence that they can accept new kinds of cargoes,” he says. And, for cargoes that need specific purity, Advanced Polymer Coatings cooperated with Shell to produce a study that definitively showed the coating could support a cargo immediately after offloading another. 

Last year, APC geared up production after signing a deal with Chinese shipowner Shandong Shipping to apply supply MarineLINE to the tanks of its fleet of eight 50,000 dwt medium range product/chemical tankers to be chartered to Shell for its ‘Shell Project Solar’ program. 

APC’s maritime-related sales grew by 40 percent in 2021, one of its most successful years in business, with the company garnering a 12 per cent share of the global cargo tank coating market. 

But while Advanced Polymer Coating and Sherwin Williams continue to hone their product offering and strengthen their market relationships, up-and-comer Repela is looking to be a game changer.

“We are trying the recreational market first because we have designed a one-season product and in the recreational boat market, seasonal reapplications are typical,” said Repeal co-founder Sheu-Jane Gallagher. “Then we will reengineer for the longer coating life required on larger vessels, for example typical drydock intervals of every five to seven years.”

On the business side, Gallagher says she believes it will be important to partner with other stakeholders as part of a strategic plan and expects the company will achieve cash-flow-positivity by the end of 2024. “We believe our technology can protect the Great Lakes and other precious bodies of water and thereby contribute to a more sustainable future for all.”

Internationally, a similar focus on sustainability and hull performance drives the product development efforts at Denmark-headquartered Hempel A/S. 

HThe company’s Actiguard low-friction fusion technology combines a silicone coating with the consistent release of limited biocides through a hydrogel layer that’s resulting in a long-lasting, fouling-resistant hull surface.

David Ippolito, who serves as Hempel’s Director of Solution Management – Marine, pointed out that “there is a general focus on sustainability in the maritime industry, because it contributes to about 3 percent of global CO2 emissions.”

Furthermore, he added, “Historically, shipowners have had little incentive to invest in technology upgrades that could improve sustainability, such as marine coatings, because fuel savings went to the charterer.” 

However, he said, with the advent of new regulations such as the Carbon Intensity Indicator regulation implemented by the IMO at the start of 2023, that is changing.

“The decarbonization push in the maritime industry is now bringing operators, charterers, as well as shipowners, together to create a need for investing in hull coating upgrades towards a more sustainable future – even for the stakeholders who do not pay for the fuel,” said Ippolito.

The International Maritime Organization’s Energy Efficiency Existing Ship Index and Carbon Intensity Indicator score vessels on efficiency. To meet targets, Ippolito explains, most shipowners are having to appraise every aspect of a ship’s operations and maintenance with the coating on a ship’s hull likely to help reduce emissions and increase performance.

Premium coatings can reduce resistance and, in turn, improve fuel consumption and reduce emissions through improved hull efficiency, said Ippolito. “These premium coatings offer a very good business case in terms of reduced operation costs, total cost of ownership and return on investment over a vessel’s entire lifespan.” 

Applied to thousands of ships in recent years, the company’s primary product, Hempaguard, is “a proven technology which helped our customers cut 5.6 million tons of CO2 emissions in 2022.”

“As more and more customers are demanding coating solutions with a better sustainability profile, lower carbon footprint, increased performance and lower total cost of ownership, we continuously innovate to deliver solutions that cater to those needs,” he said.