As they are produced from petroleum and contribute to emissions of carbon dioxide (CO2) on a large scale, conventional plastic materials pose many environmental challenges, such as resource depletion and global warming. Because of this, non-petroleum resources are attracting attention; one of these is bio-based plastic, which is made from plants and thus slashes CO2 emissions considerably since photosynthesis takes place while the plants used as materials are being grown and offsets the gas emissions. Fuji Xerox is currently working on the research and development of technology for substituting the petroleum-based plastics used in multifunction devices with bio-based plastics. Since the performance of bio-based plastics is significantly lower compared to that of conventional petro-based plastics, it is necessary to develop new technology in order to allow these materials to be used in practice.
Fuji Xerox started the full-scale research and development of bio-based plastics in 2004, and we succeeded in introducing a part made from a plastic material of which 30% or more by weight is of plant origin (maize for animal feed) in 2007. Then, after further research, we developed a new bio-based plastic material containing 50% or more by weight of a plant-derived constituent. Although our previous bio-based plastic containing 30% or more by weight of a plant-derived constituent was made from a composite resin of polylactic acid (plant-derived material) and polycarbonate (petro-based material), our newly developed bio-based plastic only uses polylactic acid. Moreover, we were able to reduce the ratio of petro-derived constituents to less than 10% by minimizing the use of them in the new additives that are used to improve the physical properties of the plastic.
Fig. 1: Comparison of flexibility before and after adding the new additives
In general, when the amount of polylactic acid used in a plastic is increased in order to raise the ratio of plant-derived constituents, both the flame resistance and the flexibility of parts deteriorate, and hydrolysis becomes more likely to occur. In order to address these shortcomings, we created improved fire-retardant additives and used a low-hygroscopic material for our new bio-based plastic, which resulted in enhancing the flame resistance and preventing hydrolysis of polylactic acid from occurring. In addition to this, we studied new additives in order to achieve higher flexibility and further strengthen the material's shock resistance (Fig. 1).
Parts made from this newly developed bio-based plastic are already being used in our products and are labeled with the BiomassPla50 mark, which is given to plastic parts containing 50% or more by weight of plant-derived constituents.
Fig. 2: A part used in our multifunction device that has been accredited with the BiomassPla50 mark