The Oxford web coater is able to deposit a wide variety of thin coatings (polymers, aluminium, other sputter-deposited layers such as oxides or metals) on a variety of substrates. Typically PET, PE or PP might be used but other polymers are possible as well as paper, textiles etc. The deposition takes place under vacuum (about 10-4torr), so the substrate and coatings (which may be as little as 10nm thick) are kept clean of debris, and solvents are not required.
Multiple layers may be deposited either simultaneously or sequentially; the web is designed to be able to rewind to allow multiple deposition in any combination without the need for the deposition sources to be sequentially arranged. The substrate may be plasma treated prior to the deposition of the coating in order to functionalize it and/or clean it.
The film width that may be handled is up to 350mm, and passes through the web at any speed within the range -1 - 5ms-1.
The deposition sources are: dual magnetron sputter deposition, resistive evaporation, monomer flash evaporation deposition with an e-beam cure to form a wide range of organic layers. Past work has focussed principally on acrylates. Mixtures of polymers have been deposited, and already the technology has been used for:
- Very high and very low surface energy layers
- Highly reflective coatings
- A variety of coloured layers and coatings with specific optical properties
- Conductive layers
- Creation of nanoparticles by incorporation of a release layer
- Adhesive layers
- Ultra high barrier films
The web coater is available for collaborative research projects with companies as well as for general hire on a daily rate. Enquiries about the facility can be made through Dr. Hazel Assender.