After the defoamer manufacturer produces the defoamer for coating, in order to ensure the quality of the product, it is necessary to check the performance. The following six test methods can be used:
1, the measuring cylinder method: add an appropriate amount of low-viscosity paint in the measuring cylinder, and then add defoamer, and observe the height of the foam at intervals after shaking.
2, high-speed stirring method: suitable for low-viscosity paint, high-speed stirring to measure the foam level.
3, the specific gravity cup method: suitable for high-viscosity coatings, coatings and defoamer are added to the homogenizer for high-speed stirring, and then the height and density of the foam are determined.
4, circulation method: the remaining paint will fall into the container after painting, and the height of the paint should be recorded at intervals.
5, bubbling method: suitable for low-viscosity paint, the air into the paint to produce foam, add defoamer after the timing to export the air, and timely record the height of the foam.
6, vibration method: repeated vibration, and then the foam density measurement.