Dielectric Belt Plasma Treatment for Uniform Web Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional atmospheric plasma treatment processes for web materials face challenges such as short coating zones and inhomogeneous treatments due to the shape of roll electrodes, leading to inefficient and non-uniform plasma treatment.
Innovation Solution
A continuous non-thermal plasma treatment process using dielectric barrier discharge (DBD) plasma at pressures of 100 Pa to 1 MPa, employing pairs of elongated or roller electrodes with endless dielectric belts to support and transport web materials, allowing for two passes through a plasma treatment zone with controlled atmosphere and reduced contamination.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If roll electrodes with short coating zones are used, then the device complexity is reduced, but the manufacturing precision and treatment uniformity deteriorate
Solution Approach 1:
The treatment process is segmented into two separate passes through the plasma treatment zone. The web material is treated on one side during the first pass, then flipped and treated on the opposite side during the second pass. This segmentation allows each pass to focus on treating one surface uniformly, resolving the contradiction between simple electrode configuration and treatment uniformity.
Solution Approach 2:
The invention adds the dimension of time and process sequence by implementing two passes through the treatment zone. Instead of attempting to treat both sides simultaneously in one pass, the process unfolds sequentially in two dimensions of treatment application, achieving uniformity without requiring complex multi-electrode arrangements.
2Stress or pressure
If conventional atmospheric plasma treatment is used, then the process can be performed at atmospheric pressure, but the treatment speed and productivity are low
Solution Approach 1:
The web material continuously moves through the plasma treatment zone in a continuous manner without interruption. The two-pass treatment is integrated into a continuous process where the material is treated on one side, flipped, and immediately treated on the other side, maintaining continuous productive action throughout the process.
Solution Approach 2:
The web material is pre-positioned and guided through the treatment zone in a controlled manner before treatment begins. The flipping mechanism is pre-arranged to ensure smooth transition between passes, and the atmospheric pressure environment is pre-established, allowing the treatment to proceed at high speed without preparation delays.
3Productivity
If the web material is treated on both sides simultaneously, then the productivity increases, but the back side of the material may be damaged
Solution Approach 1:
The treatment process is divided into two separate sequential passes rather than one simultaneous dual-sided treatment. The material receives focused treatment on one side during the first pass, is then flipped, and receives treatment on the opposite side during the second pass. This segmentation prevents the harmful effects of simultaneous treatment while maintaining high productivity through continuous operation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly increases treatment speed and homogeneity, reduces contamination, and minimizes the risk of damaging the back side of the film web material, providing a longer and more uniform plasma discharge zone for enhanced surface modification and coating.
Implementation Method 1
a continuous non-thermal plasma treatment process using dielectric barrier discharge (DBD) plasma at pressures of 100 Pa to 1 MPa
Implementation Method 2
generating plasma by applying an electric field between said electrodes
Implementation Method 3
transporting said web material using said endless dielectric belts in frictional contact with said electrodes
Implementation Method 4
the side of said web material not in contact with said endless dielectric belts is treated in two passes through said at least one plasma treatment zone
Implementation Method 5
cleaning said parts of said endless dielectric belts treated with said plasma using a cleaning station outside said plasma treatment zone
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A continuous plasma treatment process, said process comprising the steps of: providing a plasma treatment apparatus, said apparatus comprising at least one plasma treatment zone, said plasma treatment zone comprising a pair of electrodes with endless dielectric belts each having a first and a second side and each covering an electrode of said pair of electrodes; producing a non-thermal plasma in a process gas at a pressure of 100 Pa to 1 MPa in the space between said pair of endless dielectric belt-covered electrodes by applying a voltage between said electrode pair; providing a web material to be treated such that it can be transported by said two endless dielectric belts in such a way that there is an area in the plane of said belt at least about 5 mm on either side of said web material on the side of said endless dielectric belts with no part thereof facing one electrode of said pair of electrodes; transporting said web material using said endless dielectric belts in frictional contact with said electrodes such that the side of said web material not in contact with said endless dielectric belts is treated in two passes through said at least one plasma treatment zone while at the same time the exposed parts of the endless dielectric belts transporting said web material are also treated; and cleaning said parts of said endless dielectric belts treated with said plasma using a cleaning station outside said plasma treatment zone prior to said endless dielectric belts re-entering said plasma treatment zone, wherein said electrodes have a length in the transport direction of said endless dielectric belts of at least 10 mm; and an apparatus comprising: at least one plasma treatment zone, said plasma treatment zone comprising a pair of electrodes with endless dielectric belts each having a first and a second side and each covering an electrode of said pair of electrodes; a voltage power supply for each plasma treatment zone connected to said pair of electrodes such that a non-thermal plasma can be produced upon applying a voltage to said electrode pairs in a process gas in the space between each pair of endless dielectric belt-covered electrodes; each of said electrodes in said plasma treatment zone having a discharge surface and said discharge surface being in contact with a first side of said endless dielectric belts thereby shielding said discharge surfaces and the respective sides of the endless dielectric belts in contact with said electrodes from products of said non-thermal plasma; a means of transporting a web material to be treated comprising said endless dielectric belts; a process gas supply; rollers for driving/guiding said endless dielectric belts; and a cleaning station capable of cleaning products of said plasma treatment on the second sides of said endless dielectric belts therefrom.