Paint carrier foil is a thin, hard, smooth — usually white — foil pressed onto a sheet material at high pressure and temperature in the factory, serving as a base for the lacquer coat. In practice the substrate is almost always MDF; the board is sold as “lacquer-ready MDF” or “foiled MDF”.
Why the foil?
Bare MDF is a pressed fibreboard that absorbs paint unevenly. The flat face absorbs differently from the sanded and routed areas, and the fibres stand up after the first wet coat. Several primer coats and sanding passes are needed before the surface is even.
The foil seals that surface off. The result: less paint used, a more even and smoother finish, and no priming required. The foil is also reasonably wear- and impact-resistant, which helps during transport and installation.
Application
Paint carrier foil is intended for dry interior use. Common applications: joinery, furniture and shopfitting, cupboard walls, radiator casings, sliding doors, partitions, skirting and wainscoting.
Common dimensions: thicknesses of roughly 8 to 32 mm (18 mm is the interior standard), sheet widths of about 1220 to 2070 mm and lengths of about 2440 to 3050 mm.
Points to watch:
- Sawn and routed edges are plain MDF. This is the classic mistake. Treat every cut edge separately with an edge sealer or filling primer, two coats with sanding in between. Skip it and the edge drinks the lacquer, leaving a dark, rough border beside a mirror-smooth face.
- Key the surface lightly. The foil is smooth; matt it with 240 to 320 grit, then dust off or degrease thoroughly.
- Choice of lacquer. Waterborne acrylic, high-solid and PU lacquers all work. Rolling with a short-pile roller or spraying gives the cleanest result.
- Not for wet rooms. Use moisture-resistant MDF there if you must, but bear in mind that it is still not an exterior product.
- Fixings. Fill screw holes with a fine filler and treat those spots as bare MDF.
Related terms
- MDF
- Plywood
- HPL laminate
- Laminating
- Wainscoting
- Veneer
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