AQ SHIELD is a liquid glass coating that turns to glass as it dries. It protects your hull and propeller from barnacles and other fouling — beautifully, and for years — without leaching harmful substances into the sea.
Helps keep barnacles and other growth off the hull
10+ Years of Service Life
Guideline for life without recoating
Better Fuel Efficiency
Reduces hull resistancefor smoother cruising
Protects the Ocean
No antifouling agents or harmful substances leach out
About — Why Hull Coatings Are a Problem
Conventional hull coatings were designed to “dissolve, wear away, and protect.”
Typical hull coatings (self-polishing types and the like) work by slowly dissolving into seawater, releasing antifouling agents in the process to prevent growth. By design, the film keeps shrinking, so recoating every few years is a given. AQ SHIELD’s glass film was created to change that very premise.
01
Recoating costs keep adding up
Haul-out, stripping, repainting, relaunch. Every cycle costs money and leaves the boat unusable for a while — and the longer you own her, the larger the total grows.
02
Fouling steals fuel and effort
Once barnacles and algae take hold, drag increases and both speed and fuel economy fall. Removing them is heavy work, and it can damage the hull itself.
03
Antifouling agents flow into the sea
A leaching mechanism cannot be separated from its burden on the marine environment. Many owners have lived with the contradiction of “polluting the sea in order to protect the boat.”
Features — Our Three Promises
Long-lasting. Beautiful. And kind to the sea.
01
Protection that lasts — a film that doesn’t wear away
If conventional coatings are like adhesive tape — wearing away to expose a fresh surface as they foul — AQ SHIELD is like protective glass: a hard glass layer that keeps guarding the body itself. Because the film doesn’t diminish, its protection lasts for years.
Manufacturer’s guideline: 10+ years without recoating (a guideline, not a guaranteed figure)
Local damage can be repaired with a recoat (an additional coat)
Fewer recoats translate directly into lower lifecycle costs
02
Protection that stays beautiful — a surface grime can’t penetrate
Just as a drink never soaks into a glass cup, AQ SHIELD’s film simply doesn’t accept dirt. Nano-scale particles penetrate even the finest surface irregularities, creating a glass surface that is smooth to the limit.
Suppresses barnacles, algae and other growth — and what does attach comes off easily
A smooth hull also helps reduce resistance through the water
MARINEα, specialized for antifouling; MARINE, with adjustable gloss and color
03
Protection for the sea, too — antifouling that doesn’t dissolve
The main ingredient is silica — the same inorganic mineral found in sand and stone. The film contains no antifouling agents and never dissolves, so no harmful substances leach into the water. Protecting your boat is designed never to be a reason to pollute the sea.
A “petroleum-free” coating that uses no petroleum-derived synthetic resins
An inorganic composition that produces no toxic gases when burned
Once cured, the film complies with the standards of Japan’s Food Sanitation Act
Protecting your boat can also mean protecting the sea (illustration) — A glass film that leaches no antifouling agents into the water is designed to reduce the burden on the seas where fish and coral live.
Technology — The Science Behind It
“Paint it on, and it becomes glass”
Glass is normally born by melting materials at high temperatures and letting them solidify. AQ SHIELD is applied at room temperature and forms a glass-like film as it dries. At its core is the manufacturer’s proprietary “composite glass binder” technology.
How the Composite Glass Binder Is Structured
1Glass binder (outer layer)A hard, glass-like shell that encases the silica and keeps functional materials from being exposed at the surface
2Silica-based material (inner core)The binder holds the materials that deliver functions such as antifouling and rust prevention, keeping them effective for longer
3Substrate (the hull)Powerful adhesion that bonds directly to a wide range of materials — FRP, metal, wood and more
Most conventional glass coatings simply “mix” silica and similar materials into a paint binder. Because the material is exposed at the surface, performance fades easily — and, the manufacturer explains, the difference shows within about a year. AQ SHIELD’s “encapsulating” structure is what sets it apart from the rest.
Glass that doesn’t crack
Hardness alone is not enough for a hull. AQ SHIELD’s film combines toughness with flexibility, following the movement of the substrate. Another key feature is powerful adhesion from a single coat (one-coat application), with no primer required. Note that this “no primer required” applies to coating the hull; when coating a propeller, please use the dedicated primer.
Nano-scale particles
The particles are nano-sized (one nanometer is one billionth of a meter). They penetrate microscopic irregularities that ordinary waxes and chemicals cannot reach, forming a surface where dirt and organisms struggle to gain a foothold.
Shutting out the great enemies
The main causes of deterioration are ultraviolet rays, water, salt and carbon dioxide. The glass film blocks their intrusion, suppressing rust on metal and degradation of the substrate itself. What it protects is not just the “look” — it is the asset that is your vessel.
A proven field: rust & salt protection
Rust-prevention and salt-blocking technology honed in infrastructure that battles salt damage — bridges, tunnels and more — forms the foundation for applying this technology to boats, the harshest saltwater environment of all.
Films that decay, and films that don’t.
A resin film born from petroleum sits exposed to ultraviolet rays and oxygen, gradually oxidizing, fading and cracking. Silica (SiO2), by contrast, is silicon in its fully oxidized, final form. It cannot oxidize any further, and ultraviolet light cannot break it down. That is why crystal keeps its sparkle for thousands of years. AQ SHIELD’s film is a glass-like film built on this silica skeleton.
SilicaThe substance — SiO2
QuartzIts crystalline form
GlassIts melted-and-solidified form
All the same SiO2 at their origin
An analogy
Imagine placing a glass cup and a plastic cup by the seaside. Ten years later, the glass is as clear as ever, while the plastic has clouded white from ultraviolet light and oxidation. The film on your hull is the same. Which material it is made of decides what it looks like ten years on.
Technology that goes beyond the hull
At the heart of AQ SHIELD is a technology called the composite glass binder.
That is why this technology protects more than hulls alone. Rust on a boat’s steel fittings, and rot and decay in wooden decks and interior woodwork, are at root the same challenge: protecting materials from water, salt and ultraviolet light. MARINE / MARINEα are products that specialize this technology for hull antifouling — and the thinking behind them is a philosophy of longer service life that protects steel, wood and concrete alike.
* MARINE / MARINEα are products exclusively for hulls. The above describes the technology on which they are based.
Learn more about the patented technologyTechnical documentation (18 pages in total) on Japanese Patent No. 7936642, “Antifouling Coating That Suppresses Marine Organism Attachment.” Press the button below and the document opens right here on this page. (The document itself is in Japanese.)
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Comparison — See the Difference
How It Differs from Conventional Hull Coatings
A fouled hull and a clean hull, side by side (illustration) — Left: a hull with barnacles and algae below the waterline and a deteriorated coating. Right: a clean, glossy hull free of fouling.
Inorganic silica (petroleum-free); no antifouling agents used
Leaching into the sea
Antifouling agents leach out
No leaching
If fouling occurs
Mainly high-pressure washing and scraping
The smooth film surface makes removal easy; recoat repairs are also possible
Compatible substrates
Products are divided by application
Works with a wide range of substrates — FRP, metal, wood and more
* This comparison is based on the mechanisms of typical leaching-type hull coatings. Actual durability varies with the sea area, frequency of use and application conditions.
From pleasure boats to working vessels. Worries about hull fouling and recoating do not depend on the size of the boat. What AQ SHIELD has cultivated is one consistent technology: making materials last longer.
Marine Test — Proven on the Water
Immersion Test in the Seto Inland Sea
As our first step in the marine field, we ran a test with panels actually immersed in the sea. We start not with performance on paper, but with verification in real waters. That is how we work.
The immersion test panels (provided by the manufacturer). Left: surface coated with AQ SHIELD / Right: uncoated surface. After about six and a half months in the sea, the difference speaks for itself.
Test period
March 27, 2025 – October 8, 2025 (approx. 6.5 months)
Test location
Tamashima, Kurashiki City, Okayama Prefecture (Seto Inland Sea)
Test coating
AQ SHIELD Hull Coating MARINEα
What was checked
Suppression of marine organism attachment, and ease of removal when fouling occurred
AQ SHIELD MARINE / MARINEα: Japanese Patent No. 7936642 (Title of invention: Antifouling Coating That Suppresses Marine Organism Attachment) * This patent covers hull-coating technology intended for application to vessels, marine structures and coastal infrastructure. The MARINE / MARINEα products are exclusively for hulls.
How the immersion test works (illustration) — Setting the test panels → immersion in the sea → hauling out and inspecting. Please view it together with the photograph of the actual test panels above.
Products — Products & Prices
Two products, matched to your vessel.
MARINEα, with even stronger antifouling performance, and MARINE, for antifouling and rust prevention. Both are one-component products, and both can be repaired with a recoat. All prices shown exclude tax.
A can of AQ SHIELD Hull Coating
Flagship Product
AQ SHIELD MARINEα
Our flagship antifouling product, built on glass-coating technology and combined with patented magnetic technology (Japanese Patent No. 7936642). A one-component antifouling coating that contains absolutely no antifouling agents — a cause of marine pollution. Formulated with special functional nanoparticles, it suppresses the attachment of barnacles and other marine organisms. When fouling does occur, it is easy to remove, and recoating makes maintenance simple. This is the product used in the Seto Inland Sea immersion test.
Zero antifouling agents — specialized in suppressing attachment
Formulated with special functional nanoparticles
A film surface that sheds fouling easily
Ideal for underwater areas such as hulls and propellers
Fouling on a propeller (left) and a clean propeller (right) — illustrative images
Size
Price (tax excluded)
Coating coverage
1 kg
¥95,000
8 m²
4 kg
¥280,000
32 m²
15 kg
¥990,000
120 m²
Dedicated thinner
Price (tax excluded)
1 kg
¥8,300
4 kg
¥20,500
15 kg
¥64,200
AQ SHIELD MARINE
An antifouling and rust-prevention coating that can be applied to a wide variety of substrates. Once the film has formed, contaminants wash off easily with water, and recoating is possible. Unlike α, its gloss and color can be adjusted, making it suitable not only for hulls but also for topsides and superstructures — the places you can see.
Keeps antifouling and rust-prevention performance for the long term
Adjustable gloss and color, for design-conscious finishes
For a wide range of substrates — FRP, metal, wood and more
Recoatable, for easy partial repairs
Size
Price (tax excluded)
Coating coverage
1 kg
¥80,000
10 m²
4 kg
¥200,000
40 m²
15 kg
¥700,000
150 m²
Dedicated thinner
Price (tax excluded)
1 kg
¥8,300
4 kg
¥20,500
15 kg
¥64,200
Quick Cost Simulator
Just enter the area to be coated, and you’ll see the best combination of can sizes and an estimated product cost. Larger cans lower the price per m², so the simulator automatically picks the most economical combination.
Estimated product cost (tax excluded)
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Choose a product and an area, then press “Calculate.”
* Estimates cover product cost only. Application labor, thinner and surface preparation are not included. Actual quantities required vary with hull shape and application method.
FAQ — Frequently Asked Questions
Press the “+” on each item to open its answer. For anything not covered here, please use the contact form.
About the Products & Performance
The mechanism is fundamentally different. Typical hull coatings are the “leaching type”: the film dissolves and releases antifouling agents, and because the film decreases, recoating is a given. AQ SHIELD is the “non-leaching type”: a glass-like film that does not dissolve barriers the surface and suppresses attachment without using antifouling agents.
“More than 10 years without recoating” is a guideline published by the manufacturer, AQ Co., Ltd., and is not a guaranteed figure. Actual durability depends on the sea area, frequency of use, mooring environment and quality of application. We present this figure not as a guarantee, but as a guideline that shows how its design philosophy differs from conventional coatings.
The main ingredient is inorganic silica, and the coating contains no antifouling agents. Because the film itself is not designed to dissolve, no harmful substances leach into the water. And because it uses no petroleum-derived synthetic resins, its composition produces no toxic gases when burned.
Application & Coverage
Its strength is adhesion to a wide range of substrates — FRP, metal, wood and more. However, depending on the condition of the existing coating and the material, surface preparation may be required. If you are unsure, we recommend confirming with a small test application first.
It is designed so that a single coat (one-coat application) needs no primer, so the barrier to applying it is relatively low. That said, for a hull, the quality of surface preparation greatly affects the finish and durability. If it is your first time, we can help with application advice, or introduce you to an applicator.
No. AQ SHIELD can be recoated (an additional coat applied over the existing film), so scratches and local deterioration can be repaired just in that area. This is one of the factors that keeps long-term maintenance costs down.
Yes — the product is designed for coating propellers as well as hulls. Please use the dedicated propeller primer.
Choosing a Product & Prices
“MARINE” is the balanced antifouling and rust-prevention type; because its gloss and color can be adjusted, it also suits visible areas. “MARINEα” is the antifouling specialist, formulated with special functional nanoparticles, mainly for underwater areas such as the hull. If you are unsure, tell us about your mooring environment and what matters most to you — we will propose the right choice.
Product cost depends on the area. With the quick simulator above, just enter the area and it shows the most economical combination of can sizes and an estimated amount. Application costs depend on the condition of the vessel, and are quoted separately.
Yes. If you will apply it yourself or through a contractor you know, we sell the product and the dedicated thinner on their own. We will explain the application precautions at the time of purchase, so please let us know when you contact us.
Company — Company Profile
Company Name
AQ Co., Ltd.
Address
GIRAC GINZA 8F, 6-13-9 Ginza, Chuo-ku, Tokyo 104-0061, Japan
