Loading
Component parts to be surface finished are known as substrates. During the painting process, the substrate is placed onto a fixture to hold it in place, and, if required, to mask areas not intended for painting. Loading and unloading take place outside the painting unit. During unloading, components and materials which fail to meet quality requirements are removed.
Manual painting
AMB carries out painting manually, yet highly rationally, using single-component lacquer. These lacquers, which contain no curing-components, are cured in different furnaces at temperatures ranging from 50ºC to over 200ºC. During manual painting, an additional surface-smoothing lacquer is applied, improving the surface of plastic components intended for metallisation. Following metallisation, a protective clear lacquer is applied in varying degrees of gloss.
Automated painting
AMB operates a dedicated line specialising in painting metallised reflectors with silicon resin coating. The lacquer, which is applied by robots, is then baked at 120ºC.
In ourother tworobot-equipped painting units, we work almost exclusively with multi-component lacquers. In these units, the lacquer component is mixed with a setting agent, causing a chemical reaction which starts cross linking, resulting in the formation of polyurethane. We can paint up to three layers immediately one after another, making possible different combinations, such as primer, colour, top lacquer, or alternatively colour 1, colour 2, clear lacquer depending on the desired effect. We can also combine lacquering with metallisation. The possibilities areendless.
Betweenevery stage in the painting process, components pass through a so-called flash-off, during which the solvent is evaporated before the application of the next layer of lacquer.
Quality
Our automated painting lines adhere to strict quality requirements. During painting, all components are treated in cleanrooms under constant overpressure. To prevent dust entering the premises, all personnel and components are required to pass through an airlock. A well-trained eye and excellent colour vision are essential in order to work in our quality control department, and we inspect quality both before and after the painting procedure. In addition, we undergo continual evaluation of the lacquer's gloss, adhesion, and layer-thickness.
The environment
Lacquer which does not attach itself to the substrate is captured in a water curtain. The dye material is then separated and incinerated together with domestic waste. No heavy metals are used. Solvents are channelled to our incineration unit, which has a 96% degree of efficiency practically all materials are incinerated, and emissions are minimal.
For a more thorough process description, contact Jörg Hinz.