BYK®-R 606 is increasing the hydrogen bondings between the fumed silica particles. This is giving a much stronger rheology effect which allows to reduce the overall amount of fumed silica. It also avoids the viscosity drift over time by a more complete wetting of the silica. The recommended dosage is 10% based on the amount of fumed silica. The BYK®-R 606 should be added before the fumed silica.

We recommend to test 0,5 % of BYK®-W 969 calculated on the amount of filler. This will significantly reduce the viscosity.

BYK®-9076 is a very strong wetting and dispersing additive. It significantly reduces the viscosity to be able to put more ATH into the system. It is recommended to add the BYK®-9076 before adding ATH.

Our rheology additive BYK®-430 is creating a pseudoplastic flow behaviour. The higher viscosity at low shear stress will prevent the settling of the particles.

First recommendation for this application is BYK®-016. It is a polymer defoamer which complies with FDA §175.300 and PIM 10/2011 regulation without restrictions. Recommended dosage is 0.3 -0.5 %.

We have seen 0.3 % of BYK®-1790 as a very efficient defoamer for UV curing acrylic adhesives. The defoamer BYK®-1790 is based on polymers and has no negative impact on adhesion properties.

You can use HORDAMER® PE 02 which is added into the cooling water system at a dosage of 1 to 4 % based on the amount of water in your system. HORDAMER® PE 02 is a stable dispersion of a primary polyethylene in water. Even at low dosages it will remain stable and not separate and float on the water surface. On the pellets it creates a very thin layer of product to avoid the blocking. The product complies with FDA §175.200. In most of the water cooling systems the HORDAMER® PE 02 will tend to stabilize foam. We recommend to add 0.05 to 0.2 % of a defoamer such as the polymer defoamer BYK®-014 or the modified silicone defoamer BYK®-022.

Main reasons for these difficulties are the differences in surface tension of your acrylic adhesive and the surface tension of the polyester film. Adding 0.3 % of BYK®-349 will significantly reduce the surface tension of the adhesive to achieve a homogeneous wetting of the polyester film. BYK®-349 is a modified silicone surfactant and according to our knowledge does not have a negative impact on adhesion properties. A silicone-free alternative would be 0.5 to 1 % of BYK®-3410 to achieve a good substrate wetting. This product tends to stabilize foam. When you have already got a defoamer in your system, this is often enough. If not, we recommend to add 0.2% BYK®-014.

We have seen an improved adhesion in this application when adding HORDAMER® PE 02 into the water based adhesive. HORDAMER® PE 02 is more seen as a part of the binder and therefore dosages of 20 to 40 % are necessary. HORDAMER® PE 02 is a very polar primary polyethylene dispersion in water.