The manufacture of technical filters employs almost exclusively nonwoven mono-filament/multi-filament filter material, which is made of plastic such as polypropylene, polyamide or polyester and/or polymer impregnated papers. This material is processed to make filter membranes, which must then be sealed to filter end caps. However, the hydrophobic properties of these plastics make secure bonding without leakage difficult. Leakage indicates puncture in the membrane, making it unusable.
Openair® plasma offers a highly efficient solution to this problem. Both the membranes and the polymer filter end caps are pretreated through an integrated, inline plasma process before they are connected using the filter sealing compound. Plasma pretreatment effectively increases the adhesion capacity of the polymer filter material for a trouble-free, secure bonding during sealing. The result is a high-quality filter.
Kunststoffe international (01/2020)
YEARBOOK OF SEALING AND GASKET TECHNOLOGIES 2020