As OEM’s and electronics assembly firms look to comply with various market-based environmental compliance requirements, many have begun to specify that the individual components used to construct the final assembly be “Halogen Free”. While the debate regarding the scientific soundness and potential over-reach of many of the standards, the fact that they are intended to provide for both consumer safety and environmental protection remains true. The purpose of this article is to provide a better understanding of chemistry behind the materials used by Rubadue Wire to manufacture our various Winding Wires products and how they can be part of an overall program to manufacture both safe and environmentally sound products to meet a variety of end uses.
What is a Halogen?
Halogens are a specific group of elements containing Astatine, Bromine, Chlorine, Iodine, Fluorine and Tennessine. These reactive, nonmetallic elements can form highly acidic compounds when combined with hydrogen. While Iodine has a variety of uses, it is not intentionally used in electronic applications or wire and cable insulation materials. Astatine and Tennessine are extremely rare elements that have no known commercial uses. The remaining three elements that are widely found in various dielectric materials and wire insulations are Bromine, Chlorine and Fluorine.
Why are Halogens a concern?
When regulations or safety standards such as IEC 61249-2-21 and others refer to being halogen free or “low halogen”, they focus on Bromine and Chlorine.
Bromine has historically been widely used in the production of a variety of flame retardant additives found in many different plastics and wire insulations. Chlorine is a key component in the production of PVC, one of the most common wire and cable insulations used on everything from power cords, to appliance wiring and hook up wires, to the jackets of USB-type and other computer interconnect cables. The risk to the consumer and environment comes when electrical insulations or other plastic containing Bromine and Chlorine are exposed to low-temperature fires such as in a building fire or in situations where the insulation is being burned off in order to recover the underlying copper or other more valuable materials. These elements combine with hydrogen and other elements to form incredibly corrosive gases that pose great risks to both personal safety and the environment in general. As such, these elements are typically limited to concentrations not to exceed 900 ppm.
Fluorine, while a halogen as noted above, is a critical element in the production of high-temperature, high-dielectric strength insulations such as pTFE, FEP, PFA, ETFE and Rubadue Wire’s TCA insulation material. While specific application standards require true halogen-free insulation material, fluorine based insulation materials or fluoropolymers, remain incredible valuable to the electronics industries. No other class of insulations have been proven to provide the dielectric strength, temperature resistance, and chemical resistance exhibited by fluoropolymers.
Halogen-Free Winding Wires
Just as Rubadue Wire works with each of our insulation suppliers to ensure compliance with REACH, RoHS and other environmental directives, we ensure that our materials also comply with the maximum allowed concentration levels for Bromine and Chlorine. IEC 61249 established a definition of Halogen Free that allows for the continued use of the high performance, high reliability insulation materials that form the basis of each of Rubadue Wire’s multi-layered winding wires while continuing to ensure consumer and environmental safety.
Be sure to contact us to discuss how Rubadue Wire can support your environmental and safety compliance programs.