BYK Additives & Instruments

Wood & Furniture Coatings

What additives can be used to improve the sandability in acid catalyzed systems?

To achieve improved sandability in your acid catalyzed system, I would recommend our micronized amide product CERAFLOUR 994. Dosage should be between 0.5 up to 2 on total formulation.

Please can you suggest an additive to prevent pinholing in acid catalyzed wood finishes? Currently using BYK-307, BYK-390 and BYK-141.

We obtain excellent results in acid catalyzed wood finishes with the following combinations: For defoaming action, we use BYK-065. Dosage should be around 0.5 and can be increased up to 1.0, if necessary. To avoid air draft sensitivity, we propose our BYK-330 (around 0.1 on total). To obtain good leveling and orientation of some matting agents, we use BYK-378 at a dosage of 0.05 on total formulation.

I'm looking for an additive to make a pseudoplastic rheology. At the moment I have an NC laquer combined with mica. This gets high vicos if I have fast application velocity.

To achieve a pseudoplastic rheology effect in solvent-based systems, we can offer you two products: BYK-430 and/or BYK-431. The effect is always solvent-dependent (works quite well with MPA, diacetonealcohol). To control whether this works in your system, I recommend the incorporation of 4 on total formulation. If this is successful, then you can figure out the real demand of your system in detail. For BYK-430, we recommend the addition of 0.1-1.5 on total formulation for anti-settling and 1.0-3.0 on total formulation for anti-sagging. For BYK-431, we recommend the addition of 0.1-2.0 on total formulation for anti-settling and 1.0-4.0 on total formulation for anti-sagging.
Technical Service Support

Would you be so kind as to recommend the product which would reduce the penetration of the waterborne pigmented stain into the wood substrate? The reason for this is the dimensional instability of the product due to the water absorption. We have to use the waterborne system because of the VOC reduction.

There are different ways, to reduce penetration of the stain into the wooden substrate: usage of 15-20% of an acryilic or PU binder in the stain, usage of 2-3%cosolvenst which are partially mixable with water, e.G Dowanol DPM, DPnB.A quicker drying time (if possible), using 5-10% of ethanol or IPA is also possible.The binder should be compatible with the alcohol.

I need your advice concerning dispersing agents which can be used in long oil alkyd enamel.

 DISPERBYK-108, ANTI-TERRA-U, ANTI-TERRA-205; 1-2% on titanium dioxide, 1-5% on inorganic and 2-10% on organic pigments.

I have a floating problem in the solvent-based PU 2K wood primer after applying the first coat by spray. I use talc and Zn-stearic as the filler. Would you please suggest which additive will solve the problem?

We have had good experience with BYK-P104 for fillers. We suggest you try approx. 2% calculated on filler.

Having created a huge market for art in benchtops, we are now seeking to radically increase the scratch resistance and increase the slip effect which to me increases the deflection of kitchen utensils which I hope would stop things denting (to a degree) the surface of our high-gloss 2-part clear wooden benchtops. Could you help us in this quest? I have been studying nanodiamonds and found them very interesting. Do you have tungsten nanotubes or could you recommend any nanotechnolgy to assist us and that we could purchase? We need a product that won't cloud our clear coats.

In our tests we could improve scratch resistance and the slip of solvent-based wood coating systems by using NANOBYK-3650. This product is a modified silica nano dispersion. The appropriate datasheet can be found in our Additive Guide on our website

Would you be so kind as to suggest some additives from your product range for 2K PU high-gloss parquet lacquer, solvent-based, application by hand roller? Lacquer must have perfect leveling and there should be no bubbles on the film of dry lacquer.

To defoam a solvent-based 2K PU parquet lacquer, try 0.3-0.5% of BYK-066 N.To improve leveling, 0.05-0.1% BYK-331 for glossy and BYK-325 for mat systems is recommended.

Can you suggest an adequate anti-settling agent which does not impair flow?

All anti-settling additives influence flow and leveling to a greater or lesser extent. BYK-P 104(1-2%) is a wetting and dispersing additive which also shows anti-sedimentation properties. BYK-410 or BYK-420 rheological additives with very good anti-settling properties already at low dosages: 0,1-0,2%. For testing, you can stir BYK-410 or BYK-420 into the final paint. To have less influence on rheology/levelling, it is better to use BYK-410 or BYK-420 during the grinding process.

I use NeoCryl XK 98 in a formulation of waterborne coating for joinery, but I have problems with *craters* when I use BYK-024 as a defoamer. I get good results with BYK-022, but from time to time I get film with craters. Please explain to me the best way to incorporate these additives. I prefer using dissolvers with 800-1,000 rpm.

We recommend the following defoamers, in function of the PVC; 0-20% PVC: BYK-024 or BYK-028, 0,3-0,8%; 20-40%PVC: BYK-022 (0,3%)+ BYK-024 (0,2-0,5%). This additive combination is mostly recommended for high viscose lacquer. For lower viscosity 0,5-0,8% BYK-028 is recommended. If  lower shear force, the stronger defoamer: BYK-022 (0,3%); BYK-024 should be added at the beginning to the formulation.Longer stirring time helps againts crater, too.

I am working at Sigma Paints SAUDI ARABIA Ltd. I am working on a project of epoxy mastic + polyamide system with bright aluminum color where I am facing color storage stability of aluminum pigments which changes its color to dark grey from silvery bright within three days of it keeping in the oven @ 60°. I am using stapa 4L grade of aluminum pigments. Is this a problem with particle size or surface treatment of aluminum pigment or is there any additive to improve the color stability of alu pigments? Does adding extenders to alu pigments decrease color stability? What grade of alu pigments do you recommend?
As you definitely know, the stability of the system depends on many parameters (e.g. resin, co-solvents, pigments, manufacturing process ...). Due to their high surface tension, the leafing pigments are not wetted by the binder and therefore float on the wet film. This effect is achieved by the use of e.g. stearic acid as lubricant. This lubricant could be oxidized and this then gives no protection of the aluminum part any more and therefore you will see the graying at the end. The leafing behavior depends on the solvents, resin polarity, acid value and at least on the water content in different substances. This is what you have to check in your entire formulation and change to the other direction, if necessary. In a paint system with strongly polar co-solvents, there is always the possibility that the leafing pigments will drop down (drown) through wetting and turn into non-leafing pigments which then gives you a worse visual appearance. The other possibility is to change the aluminum pigment from 4L to, e.g. STAPA LUXAL 4 VS. The STAPA LUXAL 4 VS is nearly the same (see attached datasheet) as the 4L, however, it has a better stabilized surface area which might help in your system as well. As a general information I've attached a guide formulation (CC Primer) just to give you a flavor of what kind of solvent, filler generally can be used. Does adding extenders to alu pigments decrease color stability? Generally not!
Technical Service Support
I'am using a water based Acrylic enamel and when it dries it pulls away from the edges of the wood, do you have a product that assists in this problem?

You could improve this phenomenon increasing the application viscosity and solid content of the paint. Beside this a reduction of the surface tension with BYK-346, BYK-331 (0,1-0,2%) and 1-2% Byketol-WS for better substrate wetting  is necessary.

We are producing matt top coats for dark wood. The appearance of the coating is very turbid and we have problems with encapsulated foam bubbles.

Our recommendation for your system is CERAFLOUR 1000. This product provides excellent matting properties combined with high transparency and additionally nice haptic. Even with higher dosages of CERAFLOUR 1000 the viscosity is quite stable and a newtonian flow behavior is observed.We applied a solventfree UV system containing up to 15% CERAFLOUR 1000 by using a curtain coater without problems regarding curtain stability. The product does not cause foam stabilization. CERAFLOUR 1000 is based on biodegradable polymer based on renewable resources with wax-like properties.

We are using a fluorine containing leveling additive in our waterborne wood coating. The product is no longer available. What is your recommedation for a substitution?

Due to environmental aspects a lot of fluorine containing products are withdrawn from the market and legislation restricts their use. To achieve substrate wetting and leveling performance at the same time additive combinations are common practice. BYK-3455 is a newly developed additive that combines excellent substrate wetting with good flow and leveling properties. In our tests we observed improved flow into wood pores, reduced picture framing and elimination of fish eyes.

We are looking for a defoamer which also works during winter time.

With BYK-093 we developed a versatile defoamer with excellent long-lasting efficiency at high and low storage temperature. BYK-093 is environmentally friendy and provides a broad application profile. Compatibility (less defects such as craters and turbidity), easy incorporation, and suitability for post addition complete the profile.

We have problems with aceton containing spraying coats. We need some slip and orientation of silica matting agents.

For such fast drying systems it is very important to avoid foam stabilization. BYK-378 is highly efficient and provides increased slip in very low dosage. Only 0.05% of BYK-378 leads to very good orientation of silica matting agents without causing foam problems. From case to case a defoamer for example 0.1% - 0.3% BYK-141 can be used in combination.

We have to eliminate aromatic solvents in the near future and are looking for a new dispersing additive for our pigment pastes.

DISPERBYK-2155 is a solvent-free wetting and dispersing additive with a unique hyperbranched structure. It has a broad compatibility with various grinding resins and let down systems as 2K, NC and AC without influence on potlife. It shows excellent viscosity reduction, deflocculation and stabilization of inorganic and organic pigments.

I am developing a new water-borne coating for parquet and need to improve the results in Taber test.

CERAFLOUR 929 is a micronized wax alloy which improves mechanical properties. Using dosages of 0.5 - 2% we achieve significantly better Taber abrasion test results without influence on surface slip.