At this year’s Tokyo Motor Show an initial concept car with a cellulose nanofibre (CNF) body was on display, which under a thin layer of paint contained both exterior and interior CNF components. These possess the same characteristics as standard sheet metal, but are markedly lighter. The two-door vehicle therefore weighs a mere 1,050 kg and is thus some 150 kg lighter than a car of conventional design. In terms of fuel consumption, this would provide savings of up to half a litre per 100 km.
Expressed simply, the new nanofibres represent a type of paper, which at least with respect to the basic raw material consists of cellulose wood fibres. However, the tiny particles that in the tree trunk have an entirely random structure are rendered parallel in a so-called hydrodynamic focusing process and thus combined to form a thread. This is reported to be more stable than steel or spun silk, which to date has enjoyed the reputation of being the strongest biological material. Nonetheless, like glass or carbon fibre reinforced plastics, for use in bodywork parts these fibres must be woven and cast in special resins, and it is estimated that at least five years will elapse before this process and its products can reach the maturity needed for serial automotive production.