“Opened a box of powder and found caking? Don’t blame the quality yet.

In most cases, the real causes come from external conditions — five points explain everything.

1. High Temperature.

The glass transition temperature of common powder coatings is around 40°C.

Once the environment exceeds this threshold, particles soften and stick together.

High-temperature exposure during transport or a hot warehouse can easily trigger caking.

2. Compression.

Bumping during transport or stacking pressure causes friction and heat, breaking the loose structure of the powder and forming clumps.

3. Humidity.

High humidity makes the powder absorb moisture, increasing surface tackiness.

Low temperatures + humidity can also cause condensation, especially in humid regions.

4. Overstorage.

Powder coatings have a shelf life (typically 12–24 months).

Beyond this period, their physical stability decreases, and caking becomes more likely.

5. Key Point: Caking ≠ Poor Quality.

These are external factors and not quality defects.

Most caking can be fixed through drying (e.g., removing moisture with a dryer) and sieving (breaking up the clumps).

Don’t panic — just handle it properly.”