Printable magnetic media is used for changeable retail displays, shelf-edge graphics, vehicle signs, whiteboard planners and educational materials. It is usually a flexible magnetic sheet with a printable face, either built in or laminated on. Because these graphics are designed to be peeled off, moved and reapplied, they take far more handling than a print that is mounted once and left alone.
That handling is the main reason to coat. Scuffing at edges and corners, fingermarks, and rubbing against other graphics in storage all wear the printed face. A coating adds a layer that takes that wear instead of the ink.
What to test
Flex
Magnetic sheet bends every time it is lifted off a surface. A coating that is fine on a flat board may crack along a repeated bend line. Peel a coated test piece off a steel surface many times and look along the bend.
Stacking
Magnetic graphics are often stored face to back. A coating that has not fully dried, or that stays slightly soft, can mark or stick to the next sheet. Allow full drying, then stack test pieces under some weight and check them.
The printable face
Printable faces vary: some are paper, some vinyl or polymer, each made for particular ink types. A solvent coating may react with some face materials. Check for curling, lifting at the edges where face meets magnet, and any softening.
Vehicle magnets
For magnets used on vehicles, the coating faces sun, rain, road grime and car washes, so UV inhibitors and water resistance both matter. Make sure the coating stays on the print face. Any coating on the magnetic back could stop it lying perfectly flat against the panel, which affects how well it holds.
Good practice
- Coat flat. Magnetic sheet is heavy and holds its shape, which makes it fairly easy to coat evenly on a flatbed or machine.
- Keep the sheet clean. Magnetic media attracts metallic dust and filings in workshops, and these will show under a coat.
- Coat before cutting where possible, then check that cut edges stay clean.
- Keep the finish practical. A satin or semi-gloss coat usually hides handling marks better than a high gloss. See choosing a finish.
Signs for shops and vehicles are a core market for many of our customers, and our retail POS and sign makers pages show how coated graphics fit into that work.
For a view on a particular magnetic sheet, send us a printed and coated offcut, or phone 01252 624 411 before you start.