Decoration
UV vacuum metallizing on cosmetic packaging: when it works
By the Good Partner production and sourcing team. 9 min read.
What the process actually does
In vacuum metallizing, a very thin metal layer is deposited onto a plastic component under vacuum. The result reads as polished metal — a bright cap or collar — without the weight, cost or tooling of a metal part. It is standard practice across cosmetic closures and collars.
Where it works well
It works best on smooth, well-defined geometries where the layer can be uniform. Closures, caps, pump heads and collars are the usual applications. The effect is particularly effective where you want a consistent metallic band across a range of components.
Where it does not
Deep re-entrant geometries and areas that are hard to reach inside a chamber deposit unevenly. Very sharp edges can build up. And the honest limitation: a metallized plastic part will never fully match a solid metal one under close inspection. Set that expectation early rather than after approval.
Durability
A metallized layer is a surface coating, not a shell. It resists handling well but can mark under abrasion, and it can be affected by certain solvents and cleaning regimes. If a part is handled a great deal, or cleaned frequently, say so at the specification stage so the coating build can be specified accordingly.
Colour
Standard metallizing gives silver or gold tones through the deposited layer. For coloured effects, or to make a cap read as painted metal, the metallized layer can be over-coated. Both routes are normal; they differ in cost and in how they age.
How to specify it
Tell your supplier the part geometry, the effect you want, and how the part will be handled and cleaned. Then approve on physical samples rather than a render — metallized surfaces photograph differently in every light condition and a photograph is not a specification.