Most flat printed signs are made on one of a handful of rigid boards, and the two names buyers hear most often are Dibond and foamex. They look similar once printed, but they behave very differently outdoors, so the choice affects how long a sign keeps looking right. This guide explains what Dibond is, how it compares with foamex (PVC foam board), and which to ask for. Suppliers of both are listed on our rigid substrates and sheet page.
What is Dibond?
DIBOND is a brand of aluminium composite sheet made by 3A Composites in Singen, Germany, which describes it as “the original aluminium composite sheet”. Each panel is a sandwich: two aluminium cover layers 0.3 mm thick bonded to a core of polyethylene, or a mineral core in the fire-rated version. The maker describes it as lightweight, extremely rigid and strong, suitable for indoor and outdoor use, with a long service life.
Other manufacturers make aluminium composite panel (often shortened to ACM or ACP) under their own brands, for example ALPOLIC in the US and the sign panels made by Laminators Inc. in Pennsylvania. In everyday UK sign-trade language “Dibond” is often used for any aluminium composite board, so if the brand matters to you, name it on the order.
3A Composites lists several DIBOND variants that matter to buyers:
- DIBOND digital, with a lacquer system designed for direct-to-substrate digital printing.
- DIBOND FR, with a mineral core for applications with stricter fire safety requirements.
- Decorative surfaces such as anodised, brushed (butlerfinish), wood-effect (decor) and super-matte (artenara) finishes, used for interior signs and shopfitting.
What is foamex?
“Foamex” is the name widely used in the UK for expanded rigid PVC foam board. 3A Composites makes it under the FOREX brand and describes FOREX as a lightweight expanded rigid PVC sheet for indoor and outdoor use. FOREX classic comes in the widest range of thicknesses, from 1 to 19 mm, and the maker lists good UV and weathering resistance, high impact strength, low water absorption and long-term exterior use of up to five years. Its fire classification is EN 13501-1 C-s3, d0 (1 to 19 mm) and BS 476-7 Class 1 (3 to 19 mm).
The maker lists the uses as signage and display panels, point-of-sale displays, screen-printed and digitally printed panels, shopfitting, wall cladding and interior design. It is easy to cut and rout, which is why it is common for shaped displays and indoor signs.
Dibond and foamex compared
| Dibond (aluminium composite) | Foamex (PVC foam board) | |
|---|---|---|
| Construction | Two 0.3 mm aluminium skins on a polyethylene or mineral core | Expanded rigid PVC sheet |
| Thickness range | Varies by product; check the product finder | 1 to 19 mm (FOREX classic) |
| Outdoor use | Indoor and outdoor, long service life | Long-term exterior use up to 5 years (FOREX classic) |
| Rigidity | Extremely rigid and strong for its weight | Lightweight, high impact strength |
| Fire-rated option | DIBOND FR with mineral core | EN 13501-1 C-s3, d0; BS 476-7 Class 1 (3 to 19 mm) |
| Typical uses | External fascia panels, wall signs, sign trays, long-term outdoor signs, shopfitting | Indoor signs, POS displays, printed panels, shaped displays, short to medium-term outdoor signs |
Which should you choose?
A practical rule of thumb: for a sign that will be outside for years, especially a large panel exposed to sun and wind, choose aluminium composite; for indoor signs, displays and shorter-term outdoor use, PVC foam board is lighter and usually cheaper. Within that rule, a few questions narrow it down.
How long does it need to last?
The manufacturer’s own guidance puts FOREX classic at up to five years of long-term exterior use. If you need a sign to last longer than that outdoors, aluminium composite is the safer specification.
Does fire performance matter?
For signs inside public buildings, on escape routes or on building facades, ask your sign maker which fire classification the specified board carries and whether a fire-rated grade such as DIBOND FR is needed. Your building’s fire strategy, not the sign maker, decides what is required.
Will it be printed directly?
Both boards are printed directly on UV flatbed printers. DIBOND digital has a lacquer designed for direct-to-substrate printing; for foam board, 3A lists FOREX print as a dedicated variant. Ask your printer which grade it uses.
What about correx?
Correx is the common UK name for fluted (corrugated) polypropylene board. It is very light and cheap and is widely used for temporary signs such as site boards, property boards and election signs. It is not a substitute for Dibond on a permanent fascia. Plastics distributors such as Laird Plastics list corrugated board alongside aluminium composite and foam board.
Fixing and finishing
The board is only part of the sign. How a panel is fixed and finished decides how it looks up close and how well it copes with weather. Flat panels can be screwed through, fixed on stand-off locators so they sit away from the wall, slid into rail or frame systems, or folded into trays with returned edges that hide the fixings. Aluminium composite can be routed and folded into a tray, which is how many fascia signs are made; foam board is usually used flat or shaped by routing. Sign fixing systems are sold by trade suppliers listed on our sign fixings, frames and hardware page, such as Sign Trade Supplies and Ashby Trade Sign Supplies in the UK.
Getting the specification right
- State the board type, brand if it matters, thickness and finish on the quote.
- Say whether the sign is indoor or outdoor and how long it needs to last.
- Ask how edges will be finished and how the panel will be fixed: stand-off locators, rails, tray returns or adhesive.
- For outdoor printed panels, ask whether a protective laminate or UV-resistant ink is included.
- For buildings with fire requirements, ask for the material’s fire classification in writing.
Sign makers buy these boards through trade distributors. Our sign materials and trade supplies page lists distributors such as Antalis UK, Pyramid Display Materials and Spicers Canada, and manufacturers such as 3A Composites and Plaskolite.
Sources
- 3A Composites, DIBOND product information.
- 3A Composites, FOREX product range and FOREX classic specifications.
- Supplier websites linked above, checked 26 October 2026.
- Search demand: Signage Resource keyword research (Google Ads data via DataForSEO), October 2026.