Arcshield MR 250 Ballast Tank and Underwater Hull Epoxy
A light-coloured, pure epoxy anti-corrosive for water ballast tanks, void spaces and the underwater hull, applied in two coats with stripe coats to edges, welds and fabrication details. The light shade helps inspection find breakdown early in a confined space.
Grade Arcshield MR 250 | Range Protective and Marine Coatings | Technology Two-pack pure epoxy anti-corrosive, light-coloured
Technical Data Sheet
Arcshield MR 250
Issue 2026.09
1. Product description
A light-coloured, pure epoxy anti-corrosive for water ballast tanks, void spaces and the underwater hull, applied in two coats with stripe coats to edges, welds and fabrication details. The light shade is there so that inspection can find breakdown early in a confined space. Where a specification calls for compliance with the IMO Performance Standard for Protective Coatings, that is a regime covering preparation grade, soluble salt limit, nominal thickness, stripe coating and inspection, and it requires a type approval or statement of compliance issued by a recognised body for the individual product, which is confirmed at enquiry rather than claimed here.
2. Features
- Light shade to aid inspection in confined spaces
- Two-coat scheme with brush stripe coats before and after each spray coat
- Applied to blast-cleaned steel or over assessed shop primer in newbuild
- Takes the tie coat specified for an antifouling or foul-release topcoat on the underwater hull
3. Recommended uses
Water ballast tanks, void spaces and underwater hulls in newbuild and repair. Where a specification calls for the IMO Performance Standard for Protective Coatings, the type approval or statement of compliance for the individual product is confirmed at enquiry.
Substrates. Abrasive blast cleaned steel to Sa 2½ for newbuild, and mechanically prepared steel with sound aged coating for drydock repair where the surface-tolerant grade is used instead. Shop primed plate is overcoated after assessment of the primer condition and any welding and burning damage.
4. Typical properties
| Property | Typical value | Method |
|---|---|---|
| Technology | Two-pack pure epoxy anti-corrosive, light-coloured | Formulation |
| Colour | Light shades chosen for inspection in confined spaces | ISO 3668 |
| Volume solids | Typically 65 to 80 per cent | ISO 3233-1 |
| Density, mixed product | Typically 1.3 to 1.6 kg/L | ISO 2811-1 |
| Dry film thickness per coat | Typically 125 to 200 µm, two coats | ISO 19840 |
| Surface drying | Typically 2 to 6 h at 20 °C, slower at lower temperature | ISO 9117-3 |
| Pull-off adhesion | Typically 5 to 8 MPa on blast-cleaned steel, against an acceptance level commonly set at a minimum of 5 to 7 MPa for immersion service | ISO 4624, ASTM D4541 |
| Resistance to water, laboratory immersion | Immersion at service temperature, typically 28 to 90 days, followed by adhesion and blistering assessment; ballast tank qualification to the IMO Performance Standard for Protective Coatings is by that standard's test regime and is confirmed at enquiry | ISO 2812-2, blistering rated to ISO 4628-2 |
Typical values, not a specification. Values for each batch are given on its Certificate of Analysis.
5. Application
| Parameter | Guidance |
|---|---|
| Method | Airless spray, with brush-applied stripe coats to edges, welds and fabrication details before and after each spray coat. |
| Surface preparation | Newbuild: abrasive blast cleaning to Sa 2½ (ISO 8501-1), profile typically 50 to 75 µm Rz (ISO 8503-2, ASTM D4417), inside the 30 to 75 µm set by the IMO Performance Standard for Protective Coatings where that standard governs, soluble salts typically 20 mg/m² or less as chloride or the limit in the governing specification (ISO 8502-6 with ISO 8502-9). Shop primed plate overcoated after assessment of primer condition and of welding and burning damage. Drydock repair on mechanically prepared steel uses the surface-tolerant grade instead. |
| Thinning | Thinner as stated on the product data, added only as needed for the application conditions. |
| Applied film thickness | Typically 125 to 200 µm dry per coat in two coats, verified to ISO 19840. |
| Application conditions | Steel temperature at least 3 °C above dew point (ISO 8502-4) and relative humidity normally 85 per cent or less during application and cure. |
| Topcoat | On the underwater hull, the tie coat specified for the antifouling or foul-release topcoat is applied within the overcoating window stated on the product data. |
Process. Airless spray with brush-applied stripe coats before and after each spray coat. Steel temperature is held at least 3 °C above dew point during application and cure, and dry film thickness is verified to ISO 19840 for the blast-cleaned steel surface. Under an antifouling or foul-release topcoat the hull scheme takes the tie coat specified for that topcoat.
6. Storage and handling
Store base and curing agent in their original closed containers in a dry, covered store, typically between 5 and 35 °C and out of direct sunlight. Shelf life is stated on the label and the Certificate of Analysis. Handle and use the product in line with its Safety Data Sheet.
7. Safety and regulatory information
Read the Safety Data Sheet before use. Safety Data Sheets and regulatory declarations are issued by our technical centre against the product and batch supplied, so they are sent on request rather than published. Request a Safety Data Sheet or declaration.
This Technical Data Sheet is published for on-screen reference. The information is given in good faith from laboratory and application experience and describes typical values; it is not a specification and does not replace a trial on your own substrate and line. Arctic Materials may revise this sheet without notice. Issue 2026.09.
Technical Data Sheets on this site are for on-screen viewing. For a controlled copy, write to tech@arcticmaterials.com.
Other grades in this range
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