Atmospheric Plasma and Helium
What is plasma?
Plasma is created by the electrical or thermal ionization of a gas. In the case of low-temperature plasma at atmospheric pressure, optimization of the ionization process produces a continuous and homogeneous plasma cloud (see image). Helium (He) from Praxair, due its unique inertness, high thermal conductivity and other unique physical properties, allows for the most stable low temperature atmospheric plasma to be formed. Adding small amounts of oxygen (O2) to the He carrier gas enables the
rapid oxidation of surface chemical groups and contaminants. By utilizing hydrogen (H2) containing gases, the plasma can reduce the surface of materials.

Why is helium key to the process?
A plasma is a partially or fully ionized gas consisting of electrons, ions, neutral species, and photons. Overall, the gas is electrically neutral. Helium provides a more uniform plasma at ambient pressure and near ambient temperatures than other inert gases.

How is the atmospheric plasma used?
Because plasma chemistry can be tailored for specific applications, plasmas can be used to modify chemical groups on surfaces, add coatings to materials, clean surfaces and much more.

Applications
Plasma surface modification dramatically improves the printability of plastic films or webs for the converting industry. Surface cleaning of aluminum and steel with atmosheric plasma greatly enhances productivity and product quality. For woven materials, atmospheric plasma treatment improves dye properties of textile fibers. Efficient reduction of metal powders is also easily achieved.

Markets
The broad range of markets that benefit from improved product surfaces and increased productivity include:
»aluminum»printing
»automotive»steel
»electronics»textiles
»packaging

Additional benefits
Surface treatments based on plasma can have lower operating costs than alternative technologies. In addition, a low temperature plasma process does not produce a waste stream or any other by-product, which makes the process environmentally friendly.

Equipment
Enercon Industries' proprietary Plasma3™ system is the world's first Atmospheric Plasma Treatment system for the optimal treatment and functionalization of web surfaces.

Helium carrier gas plus a reactive gas pass through high voltage electrodes at radio frequency excitation. The electrodes ionize the gas mixture into a plasma. The electrode configuration depends on the topography (i.e., roughness and shape) of the surface to be treated. A flat surface would use an electrode that hovers only one millimeter or more over the surface.

» Learn more about Enercon Industries
» Read more about the Praxair and Enercon arrangement


Plasma-web interface (photo courtesy of Enercon Industries)