Motor vehicle component comprising sol-gel coating

CA 02625751 2014-05-20

Motor Vehicle Component Comprising Sol-Gel Coating

The invention relates to a motor vehicle component, particularly a motor vehicle attachment part, preferably a motor vehicle exterior component, particularly preferred a motor vehicle trim component, made of anodized aluminum or an anodized aluminum alloy.

Conventional motor vehicle components made of aluminum are brushed or anodized. These components are exposed to mechanical and chemical stress. Components of this type, for example, come in contact with cleaning agents when the motor vehicle is washed. If the cleaning agents used have corrosive effects, this results in a visible impairment of the surfaces of the motor vehicle components.

It is therefore the object of the invention to create a motor vehicle component, whose surface has high resistance to ambient influences and other stresses, particularly acids, lyes, and solvents.

This object is achieved according to the invention in that the component is provided - at least partially - with a sol-gel coating, particularly after anodization. A sol-gel coating particularly shall be interpreted as a colloidal solution (sol) of inorganic, catalytic silicon oxide particles, wherein the solution is converted into a gel by gelation and used as a coating for especially an anodized motor vehicle component made of aluminum or an aluminum alloy. Consequently, the sol-gel coating forms a coating film on the motor vehicle component.

Due to the inventive sol-gel coating, the motor vehicle component, which is made of anodized aluminum or an anodized aluminum alloy, is provided with excellent inherent UV protection, which is to say it has high UV resistance. Furthermore, the surface is extremely resistant, particularly scratch-resistant, as a result of the coating.

CA 02625751 2014-05-20

According to a further development of the invention, it is provided that the sol-gel coating is a siliceous sol-gel coating.

Furthermore, it is advantageous to ensure that the sol-gel coating is also a hybrid coating made of organic and inorganic ingredients.

In particular, it is provided that the ingredients are additives. Depending on the organic and/or inorganic ingredients that are used, additional surface effects of the motor vehicle components can be varied such that, for example, an easy-to-clean surface all the way to a moisture-repelling surface (lotus effect) can be achieved.

Advantageously, the organic ingredients comprised additionally in the sol-gel 10 coating and/or the organic ingredients comprised in the hybrid coating are substances of the following groups: phenyl groups and/or methacrylate groups.

Advantageously, the inorganic ingredients comprised additionally in the sol-gel coating and/or the inorganic ingredients comprised in the hybrid coating are substances of the following groups: PU silanes and/or EP silanes, wherein PU is polyurethane and EP is epoxy.

According to a further development of the invention, it is provided that the sol-gel coating has a thickness of 0.5 pm to 5 pm.

Furthermore, the sol-gel coating advantageously is configured as a colorless, transparent sol-gel coating. Alternatively, it is also possible to add colored additives, particularly pigments, in order to achieve a colored configuration of the surface.

The invention further relates to a motor vehicle having a motor vehicle component, which comprises a sol-gel coating according to the above description. The motor vehicle attachment, for example, is a window shaft cover, a roof rail, or a trim molding of a motor vehicle, wherein the motor vehicle component is made of aluminum or an aluminum alloy. The surface of the motor vehicle component is anodized. The motor vehicle component is provided, at least partially, with a sol2

CA 02625751 2014-05-20 gel coating, particularly from the outside. As a result of this coating, the component has high chemical resistance to most acids, lyes, and solvents. The sol-gel coating has a closed-pored surface and is not only resistant to corrosion, weathering, and light, but additionally may also be characterized by additional features, such as particularly high dirt repellent and easy-to-clean properties. It is also possible to implement the sol-gel coating as a glossy or matt coating. A satin effect is also possible.

According to a preferred example, the motor vehicle is provided with a sol-gel coating by immersion. Alternatively, and as a function of the coated component geometry, it is also possible to spray on the sol-gel coating or apply the sol-gel coating by cylindrical rolling. This type of application achieves a particularly constant layer thickness.

Furthermore it is advantageous to apply the sol-gel coating in a thickness of 0.5 pm to 5 pm, so that only relatively little coating material is required and at the same time the above-mentioned excellent results are achieved.

Figure 1 illustrates the invention by way of an exemplary embodiment. Figure 1 shows the cross-section of a motor vehicle component, for example a trim molding 1, which is made of aluminum. The surface of the trim molding 1 is anodized. Colorless or colored anodization may be provided. In particular, it is provided that a certain roughness of the surface is adjusted with the type and duration of the anodization step. After anodization, a sol-gel coating is applied to the trim molding 1 by spraying, cylindrical rolling, immersion, doctoring, and/or flat rolling and cured by means of a tempering process. The sol-gel coating 2 is incombustible and heat and fire resistant. In the event of a fire, no gases develop from the coating 2. The coating material preferably comprises exclusively inorganic components. Alternatively, however, it is also possible that organic components are present. A combination of organic and inorganic components is also conceivable.