Printing on rigid materials

Dibond (aluminium composite, ACM)

Two thin aluminium sheets with a polyethylene core in between. Dibond is a brand name that has become generic; you'll also see it called aluminium composite panel or ACM. The usual thickness is 3 mm, which covers almost every plaque and panel, and large formats get a rear frame for support. It works just as well indoors as outdoors: it doesn't absorb water, doesn't corrode and stays flat in the heat. With a UV laminate it lasts several years outside, although sun exposure is what decides most.

We print it directly with UV ink, or with printed, laminated vinyl when the piece faces a harsh outdoor setting or has to be folded. It takes contour cutting, drilling with standoffs, V-groove routing to fold edges and make boxes, and mounting on a frame. It's the material for company plaques, facades, outdoor wayfinding and large wall panels. Don't choose it for an indoor campaign lasting a few weeks, where PVC does the job for less, or for pieces that get assembled and taken down many times: a knock on a corner dents the aluminium.

Full guide: printing on Dibond →

Foam PVC (Forex)

A closed-cell PVC sheet: light, white, matt and very easy to cut. Forex is another brand name turned generic; in the workshop it's also called expanded PVC. Standard thicknesses are 3 mm for hanging or stuck-on signs, 5 mm for wall panels and freestanding pieces, and 10 mm when you need body or a visible edge. Indoors it lasts for years. Outdoors it works for temporary use in sheltered spots: in direct sun, especially in dark colours and large formats, it tends to bow.

It's printed directly with UV ink, with very good colour on the white surface, or with laminated vinyl if the piece will be handled a lot. It takes contour cutting, drilling, slot-in feet so it stands on its own, and fixing with double-sided tape. It's the material for indoor signage, POS, campaign posters and cut-out silhouettes. Don't choose it for permanent outdoor use in full sun, for a large panel that has to stay perfectly flat, or for a piece that needs to look high-end.

Full guide: printing on foam PVC →

Acrylic (PMMA)

A rigid, clear plastic, also called methacrylate or PMMA, that looks like glass but is lighter and less fragile. It comes clear, opal (the one that diffuses light in light boxes and backlit letters), coloured, black and mirrored. For signage the usual range is 3 to 10 mm: thinner sheets for small plaques and sign faces, thicker ones when you want an edge with presence. It works indoors and outdoors, is light-stable and lasts more than ten years; what ages first is the graphic if it's exposed on the front.

The most common approach is reverse printing on the back face, mirrored and with a white backing layer, so the graphic shows through the material and stays protected. Vinyl can also be applied to the back, or the front can be printed. It takes contour cutting, polished edges, metal standoffs and heat bending for lecterns and displays. It's the material for reception plaques, directories and sign faces. Don't choose it for a short campaign, for a large outdoor panel, where Dibond is more practical, or for stages with lights and cameras, because it reflects.

Full guide: printing on acrylic →

Foam board

A polystyrene foam core between two faces of card or coated paper. It's the lightest and cheapest of everything we print on, and it's mostly used in 5 and 10 mm, with 3 mm for small pieces. It's an indoor, short-life material, meant for days or weeks: damp makes it ripple, sun warps it, and a knock on the edge or face leaves a mark that won't come out.

It's printed directly with UV ink and cut straight or to shape. Adhesive hangers or cord are enough to hang it, and an easel back lets it stand. It doesn't take drilling or screws well, because the foam crumbles. We use it for presentations, talks, one-day event signage, welcome boards and short window campaigns. Don't choose it if the piece will pass through many hands, be set up at several events or sit in a busy area: foam PVC is worth it there.

Fluted polypropylene

A plastic sheet with two faces joined by internal channels, like corrugated cardboard but made of polypropylene; it's also known as corrugated plastic or Correx. It weighs very little, water doesn't affect it and it takes knocks and bending without snapping. The usual thickness is 3.5 or 5 mm. It works outdoors for temporary use, in the order of months: with prolonged sun exposure the material turns brittle and the colour fades.

It's printed directly with UV ink. It takes contour cutting, drilling and eyelets for cable-tying to fences and lampposts, and it can be folded along the flutes to make simple boxes and displays. It's the go-to board for construction-site and estate-agent signs, temporary signage at outdoor events and street campaigns. Don't choose it when the surface has to look flawless up close, because the flutes show against the light, or for a permanent piece: that calls for Dibond or PVC.

Polycarbonate

A clear plastic like acrylic, but with far higher impact resistance: it's the material that doesn't crack. For signage it's normally used between 2 and 5 mm. It handles indoor and outdoor use, and good outdoor grades carry UV protection so they don't yellow over the years. On the other hand, it scratches more easily than acrylic and its edge can't be polished to the same finish.

It's printed directly with UV ink, on the front or on the back face so the graphic is protected from scuffing. It takes contour cutting, drilling and cold bending in thin gauges. We use it in high-traffic areas, industry and logistics, plaques in places at risk of vandalism, machine guards and signage that could take a serious knock. Don't choose it if you're after the most refined finish, with a polished edge and gloss, because that's what acrylic gives you, or for everyday indoor signage, where foam PVC costs considerably less.