Say no to halogens
22 Nov 2000
NEC Corporation researchers have developed a printed wiring board (PWB) free of halogen and phosphorous compounds. The new PWB is expected to be in use in the company's electronic products by the year 2002.
PWBs are one of the main components in a wide variety of electronic equipment and frequently use epoxy resin-glass fibre laminates containing halogen compounds as a flame retardant. The use of halogen compounds, however, is an environmental concern because they can emit dioxins and other pollutants as they burn. Thus other materials are being investigated in Europe and Japan as possible replacements, including phosphorous compounds. Unfortunately, these do not offer sufficient safety capabilities.
The printed wiring board developed by NEC uses a specialised epoxy resin with a fire retardant structure and a harmless metal hydroxide element that provide for greater flame retardance and all-round safety.
As the new PWB does not use either halogen or phosphorous compounds, the board is easy to process and thermally recycle, thanks to an almost total absence of pollutant materials. By also integrating flame retardance with the board, use of the metal hydroxide is minimised while offering good electrical properties, higher heat resistance to better handle any soldering on the board, together with improved moldability and processing characteristics.
For further information, visit the NEC home page at: http://www.nec-global.com
