Issues and Technical Resolutions in Water-based Steel Drum Paint

1. Contraction

During the painting or drying process of the paint film, the surface of the topcoat may exhibit wrinkles, shrinkage, and deformation. This particular defect is most commonly observed in alkyd paint repair operations.

Cause:

Improper drying methods result in uneven drying of the paint surface. If the newly applied paint layer is dried too quickly or subjected to forced drying, or if the temperature within the paint shop is excessively high, the surface paint dries rapidly and contracts. This, in turn, delays the drying process of the underlying paint layer. When the inner coating eventually dries, it causes the surface coating to shrink. To avoid this, refrain from painting in workshops with unsuitable temperatures or those experiencing significant temperature fluctuations.

2. Elevation

Elevations, also known as wrinkles, manifest as protrusions during the spraying or drying process of the paint film. These bumps can assume various shapes due to the expansion of the paint surface.

Cause:

1. Inadequate cleaning of the underlying layer. For instance, if grease or wax on the bottom surface is not thoroughly removed, the subsequently applied paint fails to adhere properly due to the interlayer effect.

2. Insufficient interval time between the first and second sprayings, depriving the primer of ample drying time. Consequently, the moisture present in the wet paint surface corrodes the primer or topcoat, rendering it soft.

Correction method:

Smooth out the defective area through careful polishing, ensuring not to wear through the surface, and proceed with repainting.