What is the hollow filament?
Customers might confused about the what is the hollow filament, Hollow filament have two kinds, one is big hollow, one is small hollow.
Big hollow, generally long size and cut them and flaggable and then make paint brush
Small hollow, generally is chemical tapered and good painting holding and release and also softer than big hollow
Big hollow is just PET material with few PBT, The advantage is cheaper and lighter
Small hollow is PET mixture PBT, More PBT , more softer, the advantage is more lighter than solid, but more painting holding and release.
The following are the inner chart of big hollow and small hollow: