Kunststoff Helmbrechts wins three TecPart awards

Kunststoff Helmbrechts AG received three GKV/TecPart technical plastic part innovation awards at K 2019.

The Helmbrechts, Germany-based molder won the first for a 3D printed part in ABS, ABS/polycarbonate and PC with a three-layer painted chrome effect.

The application replaces Chrome 6 oxide chemicals that are now restricted or even banned.

The first paint layer provides an adhesive. The second layer has metallic effect pigments and also prepares for subsequent plasma vapor deposition, followed by a 1-micron-thick protective layer, followed by a transparent lacquer layer.

Unlike plated chrome optics, the KH painted solution enables slight color changes to meet fashion trends. The entire surface also can be back illuminated.

KH Sales Director Christoph Ernst said he will go into more details in a presentation at the Dec. 4-5 Automotive Surfaces Conference in Berlin, organized by Plastics News Europe.

The company won a second award for a capacitive touch demonstrator, with symbols that remain hidden until illuminated. The polycarbonate part is decorated with a combination of in-mold labels and silkscreen printing.

Rated by KH as particularly innovative, the application uses several layers of specially colored film.

The third award is for a light conductor and its cover in the form of a seat belt lock cover — "one of the last areas in automotive interiors to be illuminated," according to the company. It uses a three-component twin-turn tool with mold halves rotating on both sides to first mold the ABS/PC inner frame with some assembly elements on the nozzle side, then it overmolds the ABS/PV outer frame on the ejector side of the mold.

As the part is finished with a polyurethane/acrylate scratch-resistant lacquer, it has to be completely free of stress, microcracks or gaps, despite different shrinkage characteristics of the ABS/PC and PC.