A sharp eye – color matching

The interior of the new Audi A3 integrates about 150 colored components; customers can choose from five color schemes. Whether it is pashmina beige or titanium gray – one requirement is always the same: All parts, from decorative trim strips to the carpeting, must be precisely matched and coordinated. Audi Quality Assurance coordinates them all and resolves any issues with suppliers.

The colored parts in the A3 interior are extremely diverse. They consist of 34 different types of semi-finished goods – such as fabrics, leathers and films – and ten types of plastic; they come from 45 suppliers across the globe. This broad variety of materials results in many difficult neighboring interactions. For example, when smooth plastic meets textured surfaces, such as in the area of the center console, the different reflectance values of the materials can generate different, undesirable colors as perceived by an observer.

Special pigments are necessary to dye parts with different material chemistries in the same color hue. All components are dyed through, and many are also painted – some with high-gloss paint. In the new A3, for example, high-gloss components include the control panel for the climate control system and the frame of the MMI monitor. UV-stabilizers in the plastics prevent colors from bleaching out over a period of years.

Quality Assurance coordinates colors in its light studio whose lighting system can be adjusted to produce three different light environments: clear daylight, warm evening light or artificial light as in a showroom. This is necessary, because individual materials give a different color impression under different lighting conditions. This effect – known as metamerism – must of course be avoided.

All employees participating in color matching efforts must first pass a special vision test, because the optical measuring instruments at Quality Assurance – such as the spectral photometer – can only provide objective measured values of the surfaces. Such instruments cannot measure the impression the color makes on a person, because only people can simultaneously detect and evaluate color, gloss level and surface texture. Therefore, if there is any doubt, in the end it is the subjective impression of trained employees that is the decisive factor in achieving perfect color harmony.

Color matching work is also performed in the finished, assembled interior, i.e. with components in their mounted positions and from the viewing perspective of the driver. This is done, because the appearance of certain components such as pillar trim changes due to the texture of the trim material.

The equipment, data, and prices specified refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.