How must aluminium be pretreated?

Depending on the quality requirements (indoor or outdoor) and geometry (profile or sheet metal), there are different possibilities depending on the paint finish.
For liquid paint, for example, dust blasting can be far-reaching.
For powder coating we recommend a wet-chemical pre-treatment. The basis is a stain degreasing where the anodic layer is removed. The clean surface is then covered by a passivation. This forms the optimal adhesion base and protects effectively against various types of corrosion.
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What's Qualicoat?

For more than 30 years, QUALICOAT has been defining, monitoring and testing the quality of pre-treatment, coating, coating technology and the correct application of coating materials for the processing of aluminium in architecture with strict standards and guidelines. The strict quality requirements of the clients are measurably implemented and costly consequential damage caused by incorrectly applied coatings is avoided from the outset.
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What's GSB?

The GSB is an international quality community for surface finishing in architecture and industry for the benefit of society.
It draws up quality guidelines and monitors their application. This is documented by the award of quality seals.