BYK Additives & Instruments

Powder Coatings

I am a chemist working on the development of various types of paint. I would like to introduce sharp creast without having pinhole structure in a powder coating paint of the 30/70 hybride type. The shade should be jet black. Please send me related formulations as well as the names of additives and related literature by e-mail.

For your purpose, I would recommend our product CERAFLOUR 967 combined with CERAFLOUR 961 or CERAFLOUR 990 (for better surface properties). With CERAFLOUR 967 you can achieve a structure finish powder coating. It is also no problem to use it in different resin systems. If you are looking for some textured effects I would like to recommend CERAFLOUR 965 or CERAFLOUR 969.

Can you give me a general recommendation which of your products are used as anti-crater and leveling additives in powder coatings (standard systems like hybrid, polyester/HAA or polyester/TGIC)?

We would recommend the following additives to you: our products BYK-360 P / BYK-368 P or BYK-3900 P are well known in the market as anti-crater and leveling additives for a broad range of formulations / dosage on total formulation is app. 1,0%. Beside these two standard additives we also have some special additives for applications like thin thickness powder coatings (BYK-3902 P), improved crater robustness (BYK-3931 P), slip properties (BYK3932 P) or better substrate wetting (BYK-364 P).

Can I use CERAFLOUR 967 to product hammer powder in polyester / TGIC system? The VISC of local polyester is higher than UCB and DSM.

Originally CERAFLOUR 967 was developed in hybrid powder coating. It also works in polyester / TGIC powder. It is important to do some tests to find the best extrusion conditions and the best dosage of the additive. We have some guideline formulations about hammertone finish (hybrid powder) on request available.

We powder-coat our product and to protect the inner surface we are looking for dip water based primer. After primer, the product needs to be powder-coated. Please let me know if the desired primer is available.

It's no problem to use a water-based primer combined with powder coat (e.g. radiators). If you are looking for additives in water-based primer you have to ask our expert of these products. If you would like to use the powder coat as primer, I would like to recommend BYK-3933 P. This new additive will improve the wetting of liquid paints on powder primers. With BYK-3933 P the surface tension will be higher than with a standard additive and due to this special effect you will have a better wetting of the liquid paint on a powder primer.

We are having a problem with corrosion due to weak substrates (galvanized steel with iron phosphate). We are trying to increase the ability of our powder to protect against corrosion and thought that maybe adhesion promoters or wetting agents could help. Any thoughts?

We recommend to use BYK-364 P. This additive is well known to improve substrate wetting due to the high polarity of the product (dosage approx. 1-1.5% on total formulation). Also on galvanized steel, I would like to recommend combining BYK-364 P with our degassing additive CERAFLOUR 961 or CERAFLOUR 962. Dosage 1% on total. These products are very efficient to avoid defects caused by escaped gas during the curing of powder coatings. There are also some other products in our product range to improve anti-corrosion properties - but to give the best recommendation we should discuss it more in detail.

I have a formulation with a high content of pigment and filler. Due to this the formulation shows a bad leveling and a strong orange peel. Do you have some additives to improve the dispering of pigments in powder coatings?"

As you know, there are several different kinds of pigments possible. Within our product range we have three Processing Additives to improve the acceptance of pigments and fillers in resins. It's not only an improved dispersing, the whole process will be improved - like throughput in the extruder, optical appearance and outgassing. BYK-3951 P has strong pigment affinic groups and is the best recommendation for titanium dioxide and fillers. BYK-3950 P has also pigment affinic groups but this additive works more in general. The third one is BYK-3955 P which is the best recommendation for carbon black pigments and also for some organic pigments. Typical dosage for all these additives is 1-2% on total formulation. Please note - you have to use these additives in combination with a leveling additive.

Do you have an additive to get a better compatibility between different powder coatings? We often have some problems of contaminations and this results in craters.

BYK-3900 P works as standard leveling additive in a broad range of formulations and gives an improved tolerance against contaminations. BYK-3931 P is used as synergist to improve the anti-crater effect of all standard leveling additives. BYK-3931 P is used in combination (dosage 0,2 - 0,4%) on total formulation. Please contact our technical service team to get the best recommendation regarding compatibility.