How-to · Nº 17
How to make labels stick to metal
Bare metal is easy to stick to — aluminium is very high surface energy (~840 dyne/cm), so almost any permanent adhesive grips. The catch is what is on the metal: oil and machining residue are the usual reason a label fails, not the metal itself. Clean it off with isopropyl alcohol, use a permanent acrylic, and for heat or chemical exposure step up to a PET or metallized film.
Metal is the easiest surface in this whole guide to bond to. Bare aluminium’s surface energy runs to around 840 dyne/cm — far above the ~36 an adhesive needs to wet a surface, and nearly thirty times the polypropylene that defeats ordinary glues — so on clean metal almost any permanent acrylic grips on contact. The catch is that clean, bare metal is rarer than it sounds. A label meets whatever sits on the metal — an oxide skin, an oil film, a coat of paint — and that thin layer, not the metal, is where nearly every failure begins.
You'll need
- ▪70%+ isopropyl alcohol + lint-free cloth
- ▪Permanent acrylic label (film face for demanding use)
Step by step
- 01
Clean off oil and grease
Metal parts often carry machining oil or fingerprints. Wipe with 70%+ isopropyl alcohol and let it flash off — oil, not the metal, is the main cause of a label failing on metal.
- 02
Use a permanent acrylic adhesive
Bare aluminium and steel are very high surface energy (~840 dyne/cm), so a standard permanent acrylic bonds well with no special grade needed.
- 03
Match the film to heat and chemicals
For hot-fill, engine-bay or chemical exposure, use PET (−40 to +150 °C) or metallized film — not paper or BOPP, which distort with heat.
- 04
Mind coatings and paint
Powder-coated or painted metal behaves like its coating, not bare metal. A primer or a high-tack grade helps on a difficult coating.
- 05
Press firm and let it cure
Press the label evenly and let the bond cure about 24 hours before stressing it.
Bare metal is easy; the coating and the heat are the job
Two thin things stand between an easy bond and a failed one. The first is contamination: machining oil, cutting fluid or a single fingerprint leaves a microscopic film, and the adhesive grabs that film instead of the metal, then lets go weeks later. A wipe of isopropyl alcohol removes it, and skipping that wipe is the most common reason a label lifts off metal. The second is coating: a painted or powder-coated part is not metal as far as the label is concerned — it behaves like its coating, often lower-energy than raw steel, so a stubborn powder coat can need a high-tack grade or a primer.
Heat is the other axis, and it is the label that has to survive it, not the metal. An engine bay, a hot-fill line or a steam-cleaned drum calls for a PET or metallized film rated to around +150 °C, where paper and BOPP blister and curl. And where metal drums travel by sea, the marking itself is regulated: a BS 5609 system for shipped chemicals, UL 969 for safety nameplates.
Good to know
- →For chemical drums shipped by sea, use a BS5609 system; for nameplates and safety labels on listed products, UL 969.
- →Metallized film gives the silver metallic look plus hot-fill tolerance.
- →Cold metal (refrigerated or winter-outdoor) needs a warm surface or a low-temperature adhesive to bond.
Common questions
Do labels stick to metal?
Yes, easily — bare metal is very high surface energy (aluminium ~840 dyne/cm), so a standard permanent acrylic bonds well. The usual failure is oil or grease on the surface; clean it off first.
What label survives a hot metal surface?
A PET or metallized film with a heat-resistant adhesive. PET runs to about +150 °C and metallized film handles hot-fill at 85–95 °C, where paper and BOPP distort.
Not sure it'll hold?
Tell us your surface and job and we’ll spec the right material and adhesive — and ship a free sample to test.