Arcmotive EX 320 Exterior Trim Basecoat and Topcoat
A two-component aliphatic polyurethane finish for mirror housings, grilles, pillar covers and body-side mouldings, supplied as a solid colour topcoat or as a basecoat under Arcmotive EX 370 clearcoat. It is ultraviolet stabilised for extended xenon arc exposure and built to hold colour and gloss against an adjacent painted metal panel.
Grade Arcmotive EX 320 | Range Automotive Coatings | Technology Two-component aliphatic polyurethane, ultraviolet stabilised
Technical Data Sheet
Arcmotive EX 320
Issue 2026.09
1. Product description
A two-component exterior finish for mirror housings, grilles, pillar covers and body-side mouldings, supplied as a solid colour topcoat or as a basecoat for use under EX 370 clearcoat. It carries aliphatic polyurethane chemistry and ultraviolet stabilisation for extended xenon arc exposure, and it is built to hold colour and gloss against an adjacent painted metal panel. Effect and metallic colours are set to a master panel during development so that flake orientation is reproducible batch to batch.
2. Features
- Used as a solid colour topcoat or as the basecoat of the EX 320 and EX 370 system
- Aliphatic polyurethane with ultraviolet stabilisation for extended xenon arc exposure
- Colour and gloss held against an adjacent painted metal panel
- Effect and metallic colours set to a master panel so that flake orientation is reproducible batch to batch
- Electrostatic application where a conductive primer or conductive moulding provides the earth path
3. Recommended uses
Mirror housings, grilles, pillar covers and body-side mouldings in ASA, PC/ABS, polyamide and treated polypropylene, in solid colours as a topcoat, and in metallic and effect colours as a basecoat under Arcmotive EX 370 clearcoat.
Substrates. ASA, PC/ABS, polyamide and polypropylene. Polypropylene requires flame or plasma treatment, or an adhesion promoter, inside the agreed hold time before coating.
4. Typical properties
| Property | Typical value | Method |
|---|---|---|
| Technology | Two-component aliphatic polyurethane, ultraviolet stabilised | Formulation |
| Appearance and finish | Solid colours as a single-coat topcoat; metallic and effect colours as a basecoat under Arcmotive EX 370 clearcoat, matched to the approved master panel | Customer or supplier protocol, visual assessment against the master panel |
| Dry film thickness | 20 to 30 micrometres as a basecoat, 30 to 40 micrometres as a solid colour topcoat | ISO 2808 |
| Specular gloss at 60 degrees, solid colour topcoat | Held to the approved master panel, typically within plus or minus 3 units on gloss finishes | ISO 2813 |
| Cross-cut adhesion, initial and after ageing | Classification 0 to 1 with no flaking at the cut intersections, held after humidity, thermal cycling and chemical exposure | ISO 2409 |
| Pencil hardness, solid colour topcoat | F to 2H | ISO 15184 |
| Accelerated weathering, xenon arc with filtered daylight | 1000 to 2500 hours depending on the customer protocol, with gloss and colour within the agreed limit; the upper end of this window is met by the EX 320 and EX 370 system, and EX 370 is specified where the protocol calls for the longest hours | ISO 16474-2, or ISO 4892-2 where the protocol is written against the moulding |
| Colour difference after weathering | Delta E star ab typically below 1.5 against the approved master panel | ASTM D2244 |
| Multi-impact stone chip resistance | Characteristic value 0.5 to 2, tested at 23 degrees Celsius and after conditioning at minus 20 degrees Celsius | ISO 20567-1 |
| Temperature cycling | 10 cycles between minus 40 and 90 degrees Celsius with adhesion held and no blistering, cracking or flaking | Customer protocol cycle, assessed to ISO 2409 and ISO 4628-1 to ISO 4628-5 |
Typical values, not a specification. Values for each batch are given on its Certificate of Analysis.
5. Application
| Parameter | Guidance |
|---|---|
| Application method | Spray, by robot bell, reciprocator or hand gun. Electrostatic application only where a conductive primer or a conductive moulding provides the earth path. |
| Surface preparation | Clean, dry and destaticise the moulding. Polypropylene is flame or plasma treated to a wetting tension of 38 to 46 millinewtons per metre, or given an adhesion promoter, and coated inside the agreed hold time. |
| Mixing | Mix at the stated ratio, allow the stated induction time and use inside the pot life stated for the batch. Never return mixed material to the pot. |
| Dry film thickness | 20 to 30 micrometres as a basecoat, 30 to 40 micrometres as a solid colour topcoat. |
| As a basecoat | Flash off 8 to 12 minutes, then apply Arcmotive EX 370 clearcoat wet on wet with no intermediate bake. |
| As a solid colour topcoat | Flash off 8 to 12 minutes, then cure typically 30 minutes at 80 degrees Celsius part temperature, measured with a data logger travelling with the part. |
| Safety and handling | Refer to the Safety Data Sheet, issued on request against the product supplied. |
Process. Spray applied by robot bell, reciprocator or hand gun. Electrostatic application only where a conductive primer or a conductive moulding provides the earth path. 20 to 30 micrometres dry as a basecoat, 30 to 40 micrometres as a solid colour topcoat. As a basecoat, flash off 8 to 12 minutes and apply EX 370 wet on wet with no intermediate bake. As a solid colour topcoat, flash off 8 to 12 minutes and cure 30 minutes at 80 degrees Celsius part temperature.
6. Storage and handling
Store base and hardener in their original closed containers in a cool, dry, well-ventilated store, out of direct sunlight and away from sources of heat, and keep the hardener tightly sealed because it reacts with atmospheric moisture. 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
Need a Safety Data Sheet, a regulatory declaration or a grade specified to your line? Contact our technical centre.