Halogen-Free Shielding Gaskets for EMC Sealing

Würth Elektronik has introduced a halogen-free variant of its WE-LT conductive textile gaskets, targeting electromagnetic compatibility (EMC) sealing in electronic assemblies and industrial enclosures. The new product aligns with environmental compliance standards while providing measurable shielding performance for control cabinets, displays, and metal housings.

Materials and Compliance in EMC Gaskets
Conductive gaskets serve as both mechanical seals and electrical jumpers between enclosure parts to mitigate EMI and maintain ingress protection. The halogen-free WE-LT gasket family is engineered from a metallized textile bonded to a urethane foam core with pressure-sensitive adhesive backing. This material choice supports a typical surface resistance below 0.08 Ω and shielding attenuation exceeding 80 dB at 100 MHz, indicative of effective suppression of radiated emissions in the VHF band. Flammability performance meets UL 94 V-0, and the design achieves IP54 protection against dust and splashed water when correctly compressed in enclosure joints.

Halogen-free certification follows the IEC-61249-2-21 standard, reflecting industry requirements to reduce halogenated flame retardants in electronic assemblies. Compliance with the RoHS Directive and EU Ecodesign regulations further positions these gaskets for use in regions with stringent material restrictions. Reducing halogens also supports broader sustainability objectives in the electronics supply chain and product lifecycle management.

Construction and Profile Options
The conductive core comprises a woven polyester fabric with nickel-plated copper threads for corrosion resistance and wear durability; alternative configurations with an aluminum metallization layer are also available. Urethane foam cores are offered in densities ranging from 45 kg/m³ to 150 kg/m³ to match compression and mechanical resilience requirements of specific applications. A target compression ratio of approximately 30 % of the gasket’s original height is recommended to balance sealing and electrical contact continuity.

Standard profiles — including square, L-, M-, C-, D-, P-, and knife-edge shapes — enable designers to select geometries suited to different flanges, chassis edges, and enclosure interfaces. In addition to stock forms, custom shapes and cut-to-size formats are offered without additional tooling costs, facilitating integration into diverse mechanical designs.

Applications and Technical Benefits
Halogen-free conductive gaskets address EMC sealing needs in industrial control cabinets, displays, telecommunications gear, and metal housings where electrical continuity and ingress protection are required. Their dual function — providing both EMI shielding and environmental sealing — supports compliance with electromagnetic emission regulations and mechanical enclosure requirements. Designers can leverage the products to simplify assembly processes while meeting performance criteria for EMC and environmental protection.

By integrating halogen-free materials with established shielding performance, these gaskets contribute to environmentally aligned designs without compromising the electrical characteristics critical to maintaining signal integrity and regulatory compliance in complex systems.

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