What is metallising?
Vacuum metallising, or PVD (Physical Vapour Deposition), is the process of physically plating a metal material onto a plastic part in a vacuum chamber. Another term that is used is Plating on Plastic (POP).
The evaporation of the metal occurs by metal wire being in contact with a heat source (electrically charged tungsten filament) in a closed chamber under high vacuum.
The lack of pressure lowers the boiling point of the metal which causes the liquid metal to change to a gaseous phase. The metal vapour encounters the oxygen in the air forming a stable oxide layer on the surface of the components.
This gives the component an environmentally friendly, decorative metallic coating (check out our Gallery to see finished products). Metallised plastic components can be recycled and is a great alternative to traditional metal shrouds or over-shelled options which can’t be easily separated for recycling.
Preparation and jigging up
Preparation for decoration is crucial in making sure that the end result is as high quality as possible. To begin with, your products are fixed to a jig — this will carry them and avoid component-to-component contact throughout the process.
For new products, jigs will be manufactured in our tool room.
The components will then be prepared for the next phase, including processes to make sure that they are free of dust or any particles. A flame treatment may also be used, depending on the material of the component.
Some materials may also require a primer to be applied at this stage which will be done on our dedicated primer spray booth.
Base lacquer
The final stage before your products are metallised is the pre-coat and base lacquer. This is applied by automated spray guns, to ensure consistency across the products.
This base lacquer is applied so to create a consistent and quality surface finish to the component so that the metallisation process can be as glossy as possible.
The lacquered components are then placed in an oven to cure.
Metallisation
Your products are now prepared for the metallisation process.
The components (still on the jigs) are put into the vacuum metalliser, where an electrical charge is applied to aluminium.
The process reaches a stage where the metal evaporates in the chamber and adheres to the surface of the components.
In order to get a consistent covering of the vaporised metal, the components on the jigs are rotated around the chamber, giving them the chrome-like finish.
Top lacquer
To finish off the products, a top coat of lacquer is required. This coating can be a clear coat to preserve the natural gloss silver finish.
Alternatively, for a tinted finish (e.g. gold, rose gold or any other colour you desire), additives are introduced.
Minimum order quantities apply for custom colours and we can match to target samples or Pantone colours.
The final lacquer is key in protecting the metallic coating and ensuring that the metallised finish is durable.