Color flop

The thickness of the Ti02 layer is decisive for the brilliance or interference effect under regular viewing conditions whereas the transparent colorant dominates at all other viewing angles. A deep, rich color with a luster flop at all angles can be attained. If interference color and masstone of the colorant are different, a color flop (two-tone pigments) is seen in addition to the luster flop. 

Acrylic core-shell polymers have been used as principal pxjlymers for aqueous metallic basecoat paints [37—40]. The anionic shell allows pseudoplastic flow behavior which ensures parallel orientation of the aluminium pigments in the wet paint film. This orientation and the low solids content are responsible for the metallic gloss and high color flop (change in color observed on varying the viewing angle) of the basecoats. 

This isoindoline nickel complex pigment is mainly recommended for the coloration of metallics and effect coatings, especially for water based systems. P.R.271 affords yellowish to medium red shades, providing a bright flop in metallics. Alkyd/melamine resin systems may safely be overcoated and withstand exposure of 140°C for 30 minutes. The flow properties of P.R.271 in these systems and in polyester cellulose acetobutyrate base coat systems are good, but there is a certain tendency to flocculate. 

Iron(III) oxide crystallizes independently of the synthesis route in the a-modification (hematite) after calcination. Brilliant, intense colors are obtained with 50-250 nm layers of Fe203. Absorption and interference colors are formed simultaneously and vary with layer thickness of iron oxide. Especially, the red shades are extremely intensive because interference and absorption enhance each other (Fig. 79). It is possible to produce an intense green-red flop with different viewing angles at a layer thickness similar to a green interference [5.228]. 

Nacreous and interference pigments are used as colorants or part of color formulations for all applications where traditional pigments are used, but where additional color depth, brilliance, iridescence, color shift (flop), and other spectacular effects are desired [5.253]. Mica-based pigments dominate their combination of pearl and interference effects, brilliance, stability, and weather resistance is unsurpassed. Furthermore, they are non-toxic [5.221],... 

Pearl luster pigments are used to obtain pearl, iridescent (rainbow), or metaUic effects, and in transparent color formulations to obtain briUiance or two-tone color, luster flops, and color travel effects (changing with viewing angle). The most important appUcations are plastics, industrial coatings, printing inks, cosmetics, and automotive paints. 

Figure 12.6 Stereo view of the Raptor surrogate for the thyroid receptor p with the largest ligand of the training set depicted. The front section has been clipped to display inner (wireframe) and outer shells (smooth surface). Areas colored in brown represent hydrophobic properties areas in red correspond to H-bond acceptors, areas in blue to H-bond donors and green reflects H-bond flip-flops. See color plates.

Figure 12.7 AhR surrogate with a bound aza-PAH as generated by Quasar. For clarity, the front section has been clipped. Areas colored in gray/brown represent hydrophobic properties areas in green H-bond donor functions areas in yellow indicate H-bond acceptors and purple domains correspond to H-bond flip-flops. No salt bridges are observed in this model as the ligands lack any charged groups. See color plates.

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