Large liquid silicone components developed for innovative 3D printing
“One of our strengths is our role as a co-designer, supporting our partner company from the original prototypes of a new component right through to series production”, explains Karl Großalber, VP Marketing & Sales at starlim in Marchtrenk, Austria. The most recent example of a development partnership of this type is a transparent silicone tray which W2P Engineering GmbH in Vienna uses in 3D printers.
W2P Engineering is a development and engineering enterprise which specialises in 3D printers for medical applications. The auxiliary medical devices market is currently crying out for 3D printing solutions which need to be individually created for each patient. Few other processes can replicate the speed, cost-effectiveness and precision with which, for example, parts for hearing aids and dental prostheses can be produced. “We have sold a total of 250 3D printer worldwide in the past three years, including for dentistry”, says Dr. Simon Gruber, Technical Director at W2P, describing a market that continues to offer enormous growth potential. Intraoral scanners used in modern dentistry to generate an image of the jaw and tooth position provide digital data that a 3D printer can effectively use to create the required component. This can involve temporary crowns, splints or drilling templates used when fitting dental implants. The 3D printer uses light-curable photopolymers to manufacture components. These are contained in a transparent tray in which they can be exposed to light from below and cured in layers. The desired component is created layer by layer on the construction platform above the tray. Speedily and accurately.
It was exactly this tray for photopolymers that starlim developed together with its customer W2P from a highly transparent silicone approved for medical applications. “The tray, which weighs about 400 g, is one of the largest components we have ever manufactured”, says Karl Großalber. “As a recognised specialist for the production of silicone injection mouldings, we were once again able to demonstrate our market leadership in the configuration of a process for a component with a shot volume of 500 ml”. “starlim is currently the only company in the world producing the tray for our 3D printers. We’re extremely happy about this successful partnership”, stresses Dr. Gruber. A new highly transparent silicone type developed for optical applications is used in the tray and is ideal for photopolymerisation. The non-stick properties of the silicone are also exploited to the full in this application. They facilitate cleaning and have enabled the achievement of considerably longer service lives for trays, due to the lower process forces employed.
