替换城市 Principle and influencing factors of special ink defoamer agents for paints(3)

and

dioxide

anti-scratch

wetting

Most surfactants used in coatings tend to be functionally incompatible with ink defoamer. In particular, emulsifiers, wetting and dispersing agents, leveling agents, thickeners, etc. can have an impact on the effectiveness of defoamers. Therefore, when coordinating various additives, it is necessary to pay attention to the relationship between different additives and select a good balance point.

Baking temperature

additive

Polyether polyester modified organosiloxane
An organic polysiloxane with a comb like structure. N+m is about 50-250, and the molecular weight is controlled between 1000-150000. Its compatibility is adjusted by polyethers and polyesters, and the longer the chain, the better the phase compatibility. Polyether modifications are the most common in this category, typically using ethylene oxide and propylene oxide. With the increase of the content of ethoxy groups, their compatibility with water also improves, so it is also possible to synthesize water-soluble siloxane type leveling agents. Ethylene oxide and propylene oxide can be used alone or mixed to control hydrophilicity and lipophilicity. If both ethoxy and propoxy groups are contained, a silicone based leveling agent for both water and oil use is prepared,

When the paint is baked at high temperature at room temperature, its viscosity will drop at the beginning, and bubbles can move to the surface. However, because of the volatilization of solvent, the curing of paint, and the increase of surface viscosity, the foam will become more stable and retain on the surface, resulting in shrinkage and pinholes. Therefore, the baking temperature, fixing speed, and solvent volatilization rate also have an impact on the effect of defoamer.