Low-pressure (0,1-10 torr) plasma technique provides surface modification of the very topmost layers of materials without affecting the bulk properties. A wide range of applications can be transferred to different kinds of materials, natural fibres and polymers, as well as non-woven fabrics, but also metals, ceramic, etc., without having any effect on their internal structures. For example, plasma processing makes it possible to impart hydrophilic or hydrophobic properties to the surface of a fabric, or reduce its flammability. It is possible to modify materials’ surfaces by means of thin coating of tuneable composition and properties from volatile compounds. Other techniques include the grafting of chemical groups at the surface of polymers, and the etching of materials.
Particularly, properly designed plasma reactors allow the deposition of transparent gas-vapour (water) barrier films on PET (polyethylene terephthalate) and other polymers. They are made of SiOx, obtained by plasma deposition of organo-silicon precursors. When these thin, high-density thin films (100-1500 Å) are applied on suitable plastic substrates such as packaging materials, they ensure very low gas permeability (e.g.: to O2, CO2, water vapour and aromas). For example, in the case of 12-micron PET, the gas transmission rate of O2 can be reduced up to three orders of magnitude. The application of these films is compatible with industrial systems for the continuous treatment of webs (even wider than a meter) of PET, PE (polyethylene), PP (polypropylene), nylon, etc.
The technology could be useful to preserve fluids in plastic containers (gas and vapour reservoir) or packaging (bottles, packaging), preventing the loss of gas or aroma, and eventually materials release.
A wide range of polymers for food packaging can be coated with barrier films, replacing the expensive materials commonly used to keep the properties of the substances inside the packaging. A roll-to-roll plasma/sputtering reactor can be developed, able to deposit SiOx coatings on polymers (plastics) in webs (width and length of the web to be decided).
The process is quite inexpensive compared with traditional coating processes, apart from the initial investment required to build the plasma reactor and to optimise the process.
· Easy customisation
· Almost independence from the substrate
· Easy integration in production lines
PLASMA SOLUTION offers customized plasma processes and reactors for the following industrial fields:
$11. Project, design and assembly of plasmo-chemical lab-scale reactor for National and International customers;
$12. PECVD of nano-structured coating for selected adhesion of cells, bacteria and proteins for a private European research institute;
$13. Improvement of dyeability for fabrics and polymers for food and pharmaceutical packaging;
$14. detaching coatings for moulds (footwear production and automotive industries);
$15. improvement of surface properties of paper, paperboard, polymers and powders for cigarettes production (tobacco multinational company);
$16. improvement of surface properties of polymers for automotive industries.