Abstract

A process for plasma coating a surface in which an atomized surface treatment agent is incorporated in a non-equilibrium atmospheric pressure plasma generated in a noble process gas and the surface to be treated is placed in contact with the atmospheric pressure plasma containing the atomized surface treatment agent, characterized in that particle content of the coating formed on the surface is reduced by incorporating a minor proportion of nitrogen in the process gas.

IPC Classes  ?

• C23C 4/12 - Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
• B05D 5/08 - Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain an anti-friction or anti-adhesive surface
• B05D 7/24 - Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
• H05H 1/24 - Generating plasma

Abstract

An apparatus for treating a travelling porous web of material in a predetermined gaseous atmosphere comprising a process chamber (1) through which a moving web of porous material (2) is transported from an inlet at a first end of the process chamber (1) to an outlet at a second end of the process chamber (1) and a means for introducing and controlling required gas intended to provide said predetermined gaseous atmosphere in the chamber, (1). The inlet and outlet each comprise a sealing means (4a, 4b) designed to enable passage of the web of material therethrough whilst minimising the ingress of an external gas boundary layer around said material. The apparatus additionally comprises one or more intermediate chamber (s) (10) upstream of the process chamber (1) and/or one or more post-processing chamber (s) (18) downstream of the process chamber. Each intermediate chamber (s) (10) and/or post-processing chamber comprises a purging means (11) for purging the porous web (2) with a gas to replace fluid trapped in the porous web (2) a gas removing means (12) for extracting the fluids purged out of the porous web (2).

IPC Classes  ?

• D06B 23/16 - Containers, e.g. vats with means for introducing or removing textile materials without modifying container pressure
• D06B 23/18 - Sealing arrangements

Abstract

An apparatus for treating a travelling web of material in a predetermined gaseous atmosphere comprising a chamber (1) through which a moving web of material (2) is transported from an inlet at a first end of the chamber (1) to an outlet at a second end and a means for introducing and controlling gas (5) intended to provide said predetermined gaseous atmosphere within said chamber (1), wherein said inlet and outlet each comprise a sealing means (4a, 4b) designed to enable passage of said web of material (2) therethrough whilst minimising the ingress of an external gas boundary layer (3) around said web of material (2) characterised in that said apparatus also comprises one or more re-circulation channels (7, 8) adapted to re-circulate gases within said chamber (1) from the second end of the chamber to the first end of the chamber thereby negating or substantially negating any pressure difference within the chamber (1) between said inlet and outlet. Said apparatus is preferably s part of a non thermal equilibrium plasma generating apparatus or corona discharge assembly.

IPC Classes  ?

• D06B 23/16 - Containers, e.g. vats with means for introducing or removing textile materials without modifying container pressure
• F16J 15/16 - Sealings between relatively-moving surfaces