With the sol-gel coating system Saphiral EPG has developed a possibility to protect the aluminium surfaces against corrosion and mechanical stress even without anodising. Depending on the alloy and manufacturing process, the aluminium surface often shows an uneven, changed appearance after anodising, which is not visually pleasing. EPG has developed Saphiral, a coating solution that eliminates the optical disadvantages of the anodizing process. Either with the help of a topcoat adapted to the customer's colour requirements and functionalities, or the sol-gel coating can be applied directly to an uncoated surface without prior anodising. Due to the very thin layer thickness - in the range of 5 to 15 micrometers - the feel of the metal is retained. Abrasion resistance, scratch hardness and also resistance to hand perspiration, for example, can be individually adapted.