This paper presents rheological investigations of pigmented and non-pi
gmented powder coatings with the oscillation technique. The measured v
iscosity-temperature behaviour of the powder coatings exhibits a chara
cteristic viscosity minimum which strongly depends on the selected hea
ting rate. Here, the viscosity level decreases as the heating rare inc
reases, while the temperature at which the minimum occurs is shifted t
o higher temperature values. The rheological results are compared with
surface structure measurements of the final powder coating film. We f
ound that the long waviness of the surface increases at higher viscosi
ty levels. (C) 1998 Elsevier Science S.A.