Polyrise has set up a technical team and a laboratory specialized in the deposition of thin film sol gel coating. Its goal is to support our customers in the integration and the transfer of new processes of sol gel coatings. In order to meet this key-objective, Polyrise has at its disposal a platform of machines capable of implementing important industrial wet coating processes.

Dip-coating

Pilot dip coating unit with cleaning stations

Samples are immersed in a liquid varnish bath and lifted out at controlled speed. The thickness of the coating is proportional to the lift out speed. By modifying the viscosity or the dry extract of the varnish, the dipping allows for the obtention of optical precision coatings with thickness ranging from 50 nm to 50 µm.

Spin-coating

Laboratory spin coater

Polyrise is equipped as well with an industrial spin coater.

A drop of liquid varnish is deposited at the center of a part attached to a rotary disc. The rotation (at a speed of approximately 2000-3000 Rpm) induces the spreading of the varnish until obtention of a uniform film. The thickness is inversely proportional to the rotation speed but depends also on the intrinsic properties of the varnish as well as on rotation time.

Flow-coating

a YXZ flow coater system

A stream of coating material is poured over the surface of the part. The thickness of the coating depends on the slope of the surface, the viscosity of the varnish, the quantity and evaporation rate of the solvent. The excess of varnish is reused after being collected.

Spray-coating

an automatic HVLP system

A mixture of varnish and air leads to the formation of an atomized stream through a spray nozzle. The HVLP technique requires a higher air volume and a lower pressure and enable to limit the overspray and to improve the homogeneity of the coating.

Coating Processes