A powder made from a finished polymer such as nylon, polyethylene, PVC or polyolefin blends. Nothing reacts in the oven: the plastic melts onto a hot part and hardens as it cools. Films usually run thick, often 10 to 30 mils, and are applied mostly by dipping preheated parts in a fluidized bed. Typical uses are dishwasher racks, wire shelving, playground equipment and anything that needs a soft, impact-tough skin.
Those fence fittings get preheated and dipped in the PE thermoplastic, that fluid-bed grade is too coarse for the guns.
Thermoplastic coatings need heat before and after the dip, and an underheated part gives a lumpy, orange-peeled skin.
Also heard as
- thermoplastic coating
Related terms
Thermoset powder
Coating powder that melts, flows and then chemically crosslinks in the oven, so it cannot be remelted.
Fluidized bed
A tank of powder kept airborne by air blown up through a porous floor, used to dip preheated parts.
Hot flocking
Spraying powder onto a part that is already hot, so the powder melts on contact and builds a thick film.
Film build
The thickness of the cured coating, usually given in mils or microns.