Arcmetal WB 270 Water-Based Two-Component Polyurethane Finish
A waterborne two-component polyurethane finish applied at 40 to 60 microns dry over an Arcmetal PR primer, bringing the hardness, chemical resistance and exterior gloss retention of the 2K range to shops that must keep solvent content down. It cures by both water loss and crosslinking.
Grade Arcmetal WB 270 | Range General Metal Finishing | Technology Water-based two-component polyurethane, polyisocyanate cured
Technical Data Sheet
Arcmetal WB 270
Issue 2026.09
1. Product description
A waterborne two-component polyurethane finish that brings the hardness, chemical resistance and exterior gloss retention of the 2K range to a shop that has to keep solvent content down. It is applied at 40 to 60 microns dry over an Arcmetal PR primer and cures by both water loss and crosslinking. The polyisocyanate reacts with water as well as with the resin and that side reaction releases carbon dioxide, so film build per coat is held to the stated range and pot life ends without the viscosity rise that signals it in a solvent-borne product, which is why mixed material is timed rather than judged by eye.
2. Features
- Waterborne two-component polyurethane with a VOC content of 50 to 150 g/l ready for use
- Hardness and chemical resistance in line with the Arcmetal 2K range
- Tack free in 1 to 3 hours and full cure in 7 days at 30 degrees C
- Force dries in 40 minutes at 60 degrees C after flash-off
- Pot life of 1 to 3 hours at 25 degrees C, timed by the clock
3. Recommended uses
Topcoat for fabricated metal in exterior or wash-down service, over Arcmetal PR primers, in shops constrained by ventilation, solvent storage or odour where the drying conditions can be controlled.
Substrates. Arcmetal PR 210 and PR 340 primed steel, PR 210 primed zinc coated steel and aluminium, and sound abraded two-component films.
4. Typical properties
| Property | Typical value | Method |
|---|---|---|
| Technology | Water-based two-component polyurethane, polyisocyanate cured | Formulation |
| Appearance and colour | Smooth, even film; colour to the reference ordered (RAL, BS 381C, BS 4800, an IS reference or a customer panel) | Visual, against the colour reference named |
| Carrier | Water; the polyisocyanate hardener is emulsified into the base by stirring | Formulation |
| Volume solids, mixed | 35 to 45 per cent | ISO 3233-1 |
| Dry film thickness per coat | 40 to 60 microns | ISO 2808 |
| Pot life | 1 to 3 hours at 25 degrees C, roughly halving for each 10 degrees C rise; no viscosity rise marks the end of pot life | ISO 9514 |
| Drying and cure, air dry at 30 degrees C | Tack free in 1 to 3 hours; hard dry in 16 to 24 hours; allow at least 7 days for full cure, longer below 30 degrees C | ISO 9117-3 for surface drying, ISO 9117-1 for through drying |
| Specular gloss | For the sheen ordered: below 10 units matt, 20 to 45 units satin, 80 to 95 units full gloss | ISO 2813, 60 degree geometry; 85 degree geometry for matt films reading below 10 units at 60 degrees |
| Adhesion | Cross-cut classification 0 to 1 on correctly prepared substrate | ISO 2409 cross-cut |
| VOC content, ready for use | 50 to 150 g/l | ISO 11890-2, gas-chromatographic method, with the basis (including or excluding water) stated with the result |
Typical values, not a specification. Values for each batch are given on its Certificate of Analysis.
5. Application
| Parameter | Guidance |
|---|---|
| Mixing | Add the hardener to the base at the ratio stated on the labels and stir vigorously to emulsify it. Time the pot from the moment of mixing: the end of pot life shows no viscosity rise, so mixed material is timed rather than judged by eye. |
| Application method | Conventional, HVLP or air-assisted airless spray, with corrosion resistant wetted parts. |
| Substrate | Steel primed with Arcmetal PR 210 or PR 340, zinc coated steel and aluminium primed with PR 210, or sound abraded two-component films. Apply with the substrate at least 3 degrees C above the dew point. |
| Film build | 40 to 60 microns dry per coat, held within this range because the reaction of the hardener with water releases carbon dioxide; check wet film with a comb gauge to ISO 2808. |
| Drying and cure | Air dry at 30 degrees C: tack free in 1 to 3 hours, hard dry in 16 to 24 hours, full cure in 7 days. Force dry: flash-off at shop temperature long enough to release the bulk of the water, then 40 minutes at 60 degrees C; water or carbon dioxide trapped under a skinned film shows as blisters and pinholes. Air movement and relative humidity govern the drying rate. |
Process. Mix to the stated ratio with vigorous stirring to emulsify the hardener, then apply by conventional, HVLP or air-assisted airless spray; air dry, tack free in 1 to 3 hours, hard dry in 16 to 24 hours, full cure in 7 days at 30 degrees C, or force dry 40 minutes at 60 degrees C after flash-off.
6. Storage and handling
Store base and hardener in their original containers, tightly closed, in a cool, dry, covered store, protected from frost and direct sun; reclose the hardener immediately after use because it reacts with moisture. Shelf life is stated on the label and 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
Need a Safety Data Sheet, a regulatory declaration or a grade specified to your line? Contact our technical centre.