11. Jan 2023
Protective helmets made from scallop shells
Scallops are the shellfish that Japanese people eat the most. And most discarded shellfish shells are from these Scallops. Could these shells, which used to protect the animals from outside enemies, be transformed into something that protects people's lives? As a result of this question, Koushi Chemical Industry and Sarufutsu Village together developed Shellmet, a hard hat made from discarded scallop shells and recycled plastic.
Sarufutsu Village is a fishing community that generates approximately 40,000 tonnes of waste scallop shells every year. Most of the shells end up just sitting around in smelly heaps for long periods of time, as a press release states, despite some potential uses for that waste.
In a process developed by Osaka University Professor Hiroshi Uyama, the shells are first boiled and sterilized, then pulverized and processed into calcium carbonate powder. The end product are pellets of CaCO3 mixed with recycled plastic. Those 「カラスチック® (Karastic®) bioplastic pellets are subsequently given into a helmet mould and heated, causing them to melt (presumably a rotomoulding process).
After cooling the plastic melt has solidified and as a result a helmet with a scallop-shell-inspired ribbed design can be demoulded. The special design, in combination with the CaCO3 filler makes the helmet about 33% stronger than without, the press release says. In addition, the production process is claimed to generate approximately 36% fewer greenhouse gas emissions than if 100% conventional virgin plastic were used.
The first field of application for the Shellmet is the use by fisheries workers. But the helmet could also be used in disaster scenarios, such as earth quakes, or other situations in which hard hats are required. The inventors are currently applying for the necessary safety standard certification.
The Shellmet can be preordered and will be available from March 2023 in five colours: sunset pink, ocean blue, sand cream, coral white or deep black. The announced sales price is about 4,800 yen (about EUR34).