Since water evaporates much more slowly, the mechanism of metal orientation in water-based systems is significantly different. This means that the rheology of the coating is the key mechanism influencing pigment orientation. Therefore, you need to use additives that provide pseudoplasticity through certain elastic components to keep the foil flakes oriented in the coating; we strongly recommend that you test Tech-8421.

As long as the intermediate coat is sanded properly, a small amount of reactive silicone, such as Tech-2778, can be used in the intermediate coat to improve substrate wetting and resistance to crating. In wet-on-wet (non-sandable) applications, reactive silicone will reduce the surface energy of the drying intermediate coat, which can lead to scuff marks. For such applications, it is best to use Tech-2550, which reduces surface tension without significantly affecting surface energy.

In most cases, optimal leveling in two-component polyaspartic clear coats can be achieved by using highly polar modified silicones. Among active ingredients, Tech-2306 provides good wetting properties and resistance to pinholes.

For the grinding of resin-containing pigments in water-dilutable coatings and emulsions, Tech-6076, Tech-6774, and Tech-6208 are our top choices. These slurry grinding agents allow for the use of amines, thickeners, surfactants, and co-solvents. Both products provide good stability for a wide range of pigments (primarily transparent and opaque organic pigments). They can provide ideal blackness for carbon black. There is no adverse effect on the stability of pH-sensitive systems.

Generally speaking, you can choose one of the following additives to address this issue. If you are referring to a solvent-based system, you can try our Tech-58687 and/or Tech-5011 at an addition rate of 2.0–2.5% (based on pigment solids). If you are referring to a water-based system, we recommend using Tech-6208, Tech-6300, and Tech-580 in combination with Tech-9421 for aluminum foil orientation.

Start by trying Tech-6076, Tech-670, and Tech-690. We recommend using an active ingredient content of 20–30% of the phthalocyanine pigment as a wetting and dispersing agent. If you are co-milling (grinding all pigments together), we recommend calculating the amount for each pigment separately and then adding the corresponding wetting and dispersing additive.

The phenomenon you described often occurs in pigmented paint systems, and CAB is the primary culprit; the problem persists even when the pigment dispersion is stable. First, try Tech-5863, Tech-5563, Tech-5861, Tech-55561, and Tech-58687. These additives help improve the stability of general-purpose color pastes and reduce the impact of CAB. Additionally, we recommend adding CAB under high shear conditions. Deflocculation is often caused by uneven mixing. If the viscosity of the pigment concentrate is very high before adding CAB, this can also help create high shear conditions. You will need to verify these recommendations through your own experiments.