BYK Additives & Instruments

Automotive Coatings

Please tell me any additive to improve wetting and dipersing of aluminum pigment.

Generally speaking, you could choose one of the following additives for this issue. If you're talking about a solvent-based system, which I presume you are, you can try either our DISPERBYK-162 and/or DISPERBYK-110 at a dosage between 2.0-2.5 (solid on pigment). Another important thing is the orientation of the aluminum flakes to achieve a uniform appearance (avoiding cloudiness). For this, we could propose the following additives: CERAFAK-103, CERAFAK-106, CERAFAK-110, CERATIX-8461, CERATIX-8483 or CERATIX-8466. If you're talking about water-based systems, our recommendation is our DISPERBYK-180 and/or DISPERBYK-192 or DISPERYK-2060 and, for the orientation, our AQUATIX-8421 in combination with Laponite-RD.

We develop acrylic polyurethane 2K for the automotive and plastics industry. Our biggest problem is scratch resistance. We already tried 4% of 1291 CERAFLOUR 996, and it was good but not as good as we wish. First, there are still scratches, and secondly, it impairs the metallic effect and the gloss level. Any suggestion?

To improve scratch resistance, try our NANOBYK-3650, NANOBYK-3652 and NANOBYK-3610 with a dosage of 4% delivery form. Please test these additives first without any other surface active addditives. Addition of surface active additive according further tests.

I have been asked to recommend a dispersion agent for a high surface area carbon black in a solvent-based automotive top coat. Have you any recommendations to pass on?

The additive type is highly depending on the type of pigment used. Our first recommendation would be  DISPERBYK-2200, DISPERBYK®-2000, DISPERBYK®-2001. In base coat systems with a level of 70% additive solid on pigment. For top coats we recommend DISPERBYK-2013, DISPERBYK-2200 or DISPERBYK®-161 with the same level of addition. Also commercially available laboratory products (LP-products) are available, please get in contact with us in case these suggestions would be helpful.

I have problems with my water-borne pigment concentrates especially with carbon black. For certain reasons I have to add some thickener and cosolvent.

DISPERBYK-2012 is our first choice for resin-containing pigment grinds for both waterreducibles and emulsions. Slurry grind allows presence of amine, thickener, surfactant and co-solvent. DISPERBYK-2012 provides good stabilization of a wide range of pigments, mainly transparent and opaque organic pigments. With carbon blacks high jetness can be achieved. There is no negative impact on stability of pH-sensitive systems.

How can we avoid seeding when using LAPONITE-RD in waterborne base coat?

First LAPONITE has to be added slowly into demineralized water while stiring. This avoids the formation of gel particles. Also it is importatant only to add the LAPONITE solution as long as it is liquid. Postaddition of polypropylene glycole increases the using time of the LAPONITE solution drastically.

Is there any possability to improve the overcoatability of my primer surfacer?

BYK-3560 is able to increase the surface energy of the curred paint when it is able to oriented to the interface. The effect is depending on dosage and curing temperature. It can work in solventborne and waterborne systems and have no influcence onto the surface tension of the liquid paint.