Aerogen flame treatment video.
Flame treatment involves the application of a precisely defined and carefully controlled gas flame to the surface of the plastic.
The treatment is quickly applied to the material surface and changes the surface properties, significantly enhancing the material's ability to bond with a coating, UK company Aerogen reports.
For example, long glass fibre filled polypropylene (PP) is accepted within the automotive industry as a medium for the injection moulded sub structure of the car instrument panel (dashboard). It offers good structural rigidity and is cost effective, but the material has poor natural adhesion characteristics, so directly applying a durable coating to the complex shaped instrument panel proves difficult. To solve this problem flame treatment is widely accepted, effectively improving the glass fibre PP surface adhesion characteristic at low cost.
According to Eddie Grant, Global Sales Manager, Aerogen, many prestige vehicles see the instrument panel sub structure moulding flame treated prior to leather finish being bonded to the surface. Flame treatment facilitates excellent adhesion, so the leather laminate finish precisely bonds to the glass fibre PP contours for the lifetime of the vehicle. Without the flame treatment, the leather finish would de-laminate and blisters would appear, particularly around deep curves and contours.
Flame treatment of the instrument panel sub structure is also used when coating an instrument panel with alternatives to leather, such as soft touch paint or with a slushing application of a foam filler and laminate finish.
Flame treatment is typically used in place of expensive primers and as flame treatment is comparatively economical, the overall cost of a production process is reduced. Eliminating primers has the added benefit of eliminating the associated solvent emissions.