Coatings and Thin Films
Source: Pacific Northwest Laboratory
Date: 8/1/95    Record No.: 10188
Contact: John Affinito, 509-375-6942

Coatings and Thin Films
PNL has developed new processes for rapid vacuum deposition of multilayer polymer and metal films, and is pursuing applications in Li batteries, solar thermal reflector films, magnetic shielding, electrochromic films, supercapacitors, and non-linear optical devices. They achieve higher quality and production rates hundreds of times higher than other methods.

In the Polymer Multi-Layer (PML), monomer fluids are vacuum flash evaporated on the substrate. The fluid condenses as a liquid film and then is radiation cross linked to form a solid polymer film. In a second process, called Liquid Multi-Layer (LML), the liquid is directly coated onto the substrate by extrusion, rollers, spraying or other means, and then is radiation cross linked. Both of these processes are novel, fast, and compatible with simultaneous high rate in-line deposition of other layers by conventional vacuum coating processes (evaporation, sputtering, or plasma-enhanced chemical vapor). Several licenses have already been granted.

The supercapacitor consists of thousands of thin alternating layers of polymer and aluminum, and can go to very high voltage. The PML/LML processes inherently eliminate pinholes and other micro defects that can have a significant effect on the properties of the film. There is a license: AVX in South Carolina.

The solar reflector film has higher reflectivity and is cheaper than other alternatives, using acrylic/silver/acrylic layers on a polyester substrate.

Optical coatings have been done on elements 2 meters in diameter.

Electrochromic heat mirror film can become cost effective due to the high rate of production.