Free flow agent for powder coatings – TEGO® Powder Aid F05 with balanced flowability and leveling performance

Free flow agents are indispensable additives in the production and application of powder coatings, providing excellent flowability and application performance. The flowability of the powder refers to the degree to which the powder coating is fluidized by airflow in fluidization equipment, and it is also an important indicator for improving the application performance of powder coatings. Currently, Free flow agents on the market are fumed alumina or fumed silica, as well as their surface-modified products.

Good powder coating flowability is crucial in the production and application of powder coatings. Firstly, excellent powder flowability significantly enhances the efficiency during grinding and sieving stages of powder coating. Secondly, during electrostatic spraying process, powders with good flowability are very fluffy under the action of airflow, allowing for smooth transfer from the powder supply container to spraying gun, achieving excellent atomization. This helps to overcome issues such as gun blockage or powder spitting caused by poor flowability. Additionally, good powder flowability effectively reduces the clumping of powder coatings during storage and transportation, especially in high temperature or high humidity environments.

Currently, hydrophilic fumed alumina and silica offer acceptable overall performance and are widely used in powder coatings. However, due to its hydrophilic property, it tends to absorb moisture from the environment in high-temperature and high-humidity conditions. This can lead to issues if the package is not used after opening, as moisture absorption can degrade the dispersibility and flow-promoting properties of the free flow agents. Additionally, when added to powder coatings, they may not effectively enhance the anti-caking property of the powder coating.

Therefore, more and more customers prefer to use hydrophobic free flow agents because they have better storage stability and are less likely to cause bridging and clogging in pipes during the feeding process due to the good flowability of free flow agent itself. Hydrophobic fumed alumina and silica can offer good flow-promoting and anti-caking effects. However, due to their hydrophobic surface modification, they have poor compatibility with powder particles. It can negatively impact the leveling and gloss of the coating surface, which are the pain points and usage limitation of most hydrophobic free flow agents.

TEGO® Powder Aid F05 is the latest and most innovative free flow agent based on fumed silica. It is modified by hydrophobic matters, not sensitive to moisture and has excellent storage stability itself. In addition, it significantly enhances the flowability, fluidization, and anti-caking properties of powder coatings during transportation, storage and application, especially valuable for some low-bake powder coatings, powder coating with low pigment and filler loading which are easy to cake during high temperature and high humidity environment. Importantly, it has a limited impact on surface leveling and gloss, making it noticeably superior to conventional hydrophobic fumed silica and alumina.

Anti-caking (storage condition: 40°C, 60% humidity)

Levelling