Identical volumes are marked by squares and the particles are evaluated with respect to inclination
d and thickness. Due to the fact that TEM analysis need thin electron transparent sections of the
volume (prepared from both sides of the lamella) a continuous transversal shift of the interface was
followed by SEM imaging and correlated with X-ray CT images for a large volume. The Xray CT
– SEM - TEM correlation in fig. 8a, b, c was carried out only at the final stage, having a thin
lamellar residue suitable for TEM. The usage of X-ray CT evaluation of particle inclinations in
correspondence to measured goniometric lightness distributions (here light incidence is 45° and the
detection angle varies from +75° to -75°, corresponding to an aspecular angle φ from 30° to -120°)
is demonstrated in fig. 9a – for a series of different effect pigment concentrations, where the
lightness curves are shifted to higher values and fig. 9b – for a series of effect coatings with rising
disorienter concentration, with a “rotation” of the lightness curves: less lightness in direction close
to the specular and more lightness in strong aspecular directions. The behavior of log(L*)=f(φ) in
both cases fits well with the Xray CT data of particle inclinations as given in the captures.
Therefore the gonio-spectrophotometric approach and the X-ray CT data are best suited to study
the effect particle orientation distribution in a sufficient large coatings volume and SEM /TEM
analysis can be used to investigate detectability of the pigments, resolution and local peculiarities
of the methods.