MARK I 4450 is recommended for formulations where air-entrainment cause operational difficulties or impairs the quality of the product. It has also very rapid foam knock-down properties.
From 0.25 to 0.5% of defoamer on the weight of the coating solids is usually sufficient to suppress air-entrainment. The optimum amount for individual formulations can readily be determined by trial.
For adhesives, 1 to 2% of MARK DC 1450 based on the weight of the latex solids is more than sufficient.
As the product is very effective antifoam agent, a very small quantity like 200 gms to 500 gms can effectively defoam 100 Ltrs of paint. It is advisable to split the addition of defoamer by adding half the normal quantity to the pigment mix prior to grinding to suppress the formation of foam & the balance to the let down portion of the paint.