“DuPont continues to offer product innovations that deliver high value, cost effective solutions for our industry,” states Kevin Suino, Market Development Specialist for Polyester Films. “Customers continually challenge the performance limits of traditional polyester films, and these two new film types extend the limits for Design Engineers to VTM-0 certifications.”
There are other thermo engineered flame retardant products on the market, however most are higher priced. Polyimide (PI) film falls into that commercial category. And, while most polyester films have excellent resistance to heat, chemicals and water absorption, they typically are assigned a flame classification rating of VTM-2 or higher. This flame rating limits the applicable range of electronics and related applications.
Teijin® Tetoron® UF PET and Teonex® QF PEN films are both white and halogen-free films. Tekra has access to a range of thicknesses from 25 to 250 microns. Focus of product introduction has targeted insulating materials and labels for electronic products and batteries, in addition to flexible printed circuitry and lighting. These products provide more than 90% diffuse reflectance across the visible wavelength spectrum, in thicknesses of 125 or more, which is desired by many LED lighting applications. For more extreme temperature applications, Teonex® QF PEN film is capable of withstanding processing temperatures in excess of 180°C.
Other commercial film types offer inherent flame retardance, but often at a high price. Most commercial polyester films are inherently resistant to heat, chemicals and water absorption, however the typical flame classification rating is at the VTM-2 level or higher. Consequently PET polyester films have been used only in a limited range, or in some cases the PET’s flame retardance was achieved through the use of additives or coatings containing halogens, which are no longer permitted in many industries. This type of film is used in applications such as electrical insulation and flexible printed circuits and is characterised by excellent flame resistant properties. It has also good bonding strength achieveable with coatings, printings and adhesives. The films are of high mechanical strength with dimensional stability. Other applications include membrane touch switches, cables, protective clothing and overlays.