1. Controlled compatibility,that is,to achieve the balance between defoaming and surface effects,both defoaming and prevention of defects such as shrinkage cavities and poor leveling.

Formulation design system for waterborne coatings - defoaming agent and defoaming agent 2

2019-07-11

Types of defoaming agents	Character	Application
Mineral oil	Strong anti-bubble ability Low price Poor system compatibility Easy migration	Primer Matte
Organic silicon class	Strong defoaming ability higher price Different product performance differences Large adjustment space Improper selection can cause film defects Influence gloss, flow equality	Various coatings
Non-silicone non-oil	Good security Low probability of defects Does not affect the gloss But the amount is slightly larger Insufficient bubble breaking ability higher cost	Various types of coatings, especially in high gloss finishes

There are many defoamers on the market, and the choices are very cautious and can be noted in several ways:

1. Controlled compatibility, that is, to achieve the balance between defoaming and surface effects, both defoaming and prevention of defects such as shrinkage cavities and poor leveling.

2. Defoaming according to the construction conditions and methods, such as brushing, spraying and roller coating, face different degrees of foaming, and also means different defoaming agents.

3. The balance between foam suppression and foam breaking can be reasonably matched according to different processing and construction methods.

4. Long-term defoaming performance. Many defoamers will gradually reduce their defoaming performance during storage of the paint, and the antifoaming agent content in the paint should be higher when designing the formula.

The amount of defoaming agent is 0.05% to 0.5% of the whole formulation, preferably about 0.1%. If the defoaming agent used exceeds 0.5% to have a good defoaming effect, the defoaming agent should be considered.Different resin systems are sensitive to defoamers. The type and amount of aqueous defoamer selected must be determined experimentally, depending on the system.