Electrical Insulation Systems

Coil Forms in an Electrical Device

UL-Approved, Performance Tested Coil Forms and Encapsulants

From coil forms to encapsulants, solenoids to switches, DuPont helps customers meet electrical insulation standards (EIS). We offer the industry’s largest number of materials pre-approved by Underwriters Laboratories (UL) and recognized to IEC standards.

Local Experts, Global Presence

DuPont offers more than 400 pre-tested, globally approved UL/IEC electrical insulation systems. These pre-approved systems, backed by application knowledge from DuPont material science experts, can deliver significant cost and time savings. Solutions that have recognition from UL are ready to be used for end-product registration testing.

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DuPont™ Rynite® PET For Coil Forms

Rynite® PET thermoplastic polyester resin offers an excellent combination of thermal stability, electrical properties, dimensional stability and stiffness, making it ideal for coil forms and electrical encapsulation.

Specifically, Rynite® PET meets the requirements of UL94-V-0 at 0.4 mm and IEC-60335 GWT of >775°C. With a relative thermal index (RTI) of 155°C and insulation ratings of class B (130°C) to class N (200°C), this polymer offers excellent thermal endurance.

With demonstrated performance in through-hole-mounted, lead-free soldering assemblies, Rynite® PET maintains a very high dielectric strength across a wide temperature range (23˚C to 150˚C).

The Advantages of Zytel®

Zytel® nylon offers numerous characteristics for electrical component designs and requirements,which include an inherent UL94-V2 flame rating @ 0.4mm, and high arc ignition resistance of HAI = PLC0, CTI > 600 V to prevent fire hazards that can be caused by conductor arcing. Zytel® also presents high flow, toughness, and high elongation that enables flexible and thin-wall part designs.

The Zytel® nylon family includes Zytel® HTN PPA, Zytel® PLUS, and Zytel® Renewably Sourced, all offering a wide range of reinforced and flame-retardant grades that meet your different industry and application needs.

Zytel® For High-Temperature Electrical Insulation Applications

Zytel® HTN PPA resins are a family of aromatic nylon copolymers that have excellent heat resistance, making them ideal for high-temperature electrical insulation. The HTNFR52G series offers grades with a high melting point used with surface mounting, or through-hole components that require lead-free soldering.

Zytel® HTN is an ideal insulation material for minimizing fire hazards, due to its high arc ignition resistance, plus high hot-wire ignition temperature. The resin offers superior resistance to reflow soldering conditions, even after moisture conditioning.

The non-halogen series can comply with industry and major OEMs hazardous substance control requirements (JEDEC, JPCA, IPC, IEC61249), and also attain excellent flame-resistance performance (UL94-V0 @ 0.4 mm). Zytel® HTN is easy to adopt, with no concerns of upgrading from FR-PBT, FR-PET, or FR-PA, as the shrinkage factor is similar.

DuPont™ Crastin® for Connectors, Relays and Switches

Coil forms made of Crastin® PBT feature excellent dielectric and electrical insulation properties. It’s available in high-arc-resistant grades, making it the ideal electrical plastic for connectors, relays and switches. 

With outstanding mechanical and physical properties, Crastin® delivers greater reliability, increased durability, and a cost advantage over many competitive materials used in electrical and electronic applications. 

For circuit breakers, relays, and connectors, Crastin® offers low embrittlement at high temperatures, dimensional stability, easy processing, and low out-gassing.