Seven-component toothbrush mold reportedly is a world first

A German moldmaker has built what it calls the world's first seven-component mold. Designed and machined by Zahoransky Formenbau GmbH (Freiburg), the mold has been delivered to Schiffer (Neustadt/Wied, Germany) to mold toothbrushes.

The system incorporates two injection molding cells and a loading and parts removal station. The first cell processes two similarly colored materials while the second one processes thermoplastic elastomers (TPEs) in four different colors. Compared with conventional systems, productivity is significantly improved because the multicomponent architecture eliminates time-consuming color changes.

Previously, color changes meant as much as two hours of downtime in the production cycle, says Zahoransky. In addition to improving productivity, the seven-component molding technology also has a cost advantage as the absence of color changeovers means that there is no material waste.

The challenges in designing a seven-component mold included dealing with overall space constraints as well as the tight fit of the nozzles and mold cavity, and managing several material feeds at various processing temperatures.

Hot-runner technology from Mold-Masters is used in this application, primarily because of the company's two-part soldering process. Not limited to straight channels, Mold-Master hot runners can have as many as three melt levels with gentle curves and turns. Natural balancing, a uniform thermal profile, and a comparatively low construction height provide absolute design freedom, according to Zahoransky. Two or more channels can be integrated in a runner, and six or more materials and colours can be accommodated.

Seven component molding technology has allowed Schiffer to accelerate the production of toothbrushes, such that products molded and packaged on site can be on store shelves the next day.

Zahoransky supplies injection molds for a range of industries including the medical sector, as well as packaging machines, automation systems, and brush production equipment.

Schiffer produces more than one million toothbrushes daily at its dental care products facility near Köln, Germany. The company's origins date back to 1887 as a brush manufacturer.