Abstract: A process for preparing membrane layers employing an apparatus suitable for plasma surface treating (e.g. forming a membrane layer on a substrate) which comprises a plasma generation section which is operable at least at substantially atmospheric pressure and is in communication via at least one plasma inlet (e.g. a nozzle) with an enclosed plasma treating section which is operable at a lower pressure than the plasma generation section, and wherein the plasma treating-section is in communication with an inlet for a fluid (e.g. polymerizable) reactant. A plasma beam generated in the apparatus and containing at least one fluid reactant impinges on the surface of a substrate to form a membrane layer.

Abstract: An apparatus suitable for plasma surface treating (e.g., forming a membrane layer on a substrate surface) comprises a plasma generation section which is operable at least at substantially atmospheric pressure and is in communication via at least one plasma inlet (e.g., a nozzle) with an enclosed plasma treating section which is operable at a lower pressure than the plasma generation section, and wherein the plasma treating-section is in communication with an inlet for a fluid (e.g., polymerizable) reactant used to form a layer on the substrate surface.

Abstract: A method of treating substrate surfaces with the aid of a plasma such as etching, deposition etc. In the practice of the method, the plasma flows from its place of generation to the treatment-chamber, and in which method the plasma-generator is flushed through with a flushing gas. Preferably, and firstly after the flushing gas has passed the cathodes, the reactant is fed to the plasma-generator. The invention includes the reactor necessary for carrying out the method.