Future Resins from Grain - Otsu City, Shiga Prefecture, 1996

Future Resins from Grain - Otsu City, Shiga Prefecture, 1996

In the mid-1990s, Japan was going through a period of rapid economic growth followed by the bursting of the bubble economy, and the need to balance a sustainable economy with environmental preservation was coming to the forefront as a social issue. The mass-production, mass-disposal lifestyle was being reconsidered, and the environmental burden caused by waste plastics, the tightness of final disposal sites, and the toxic gases emitted during incineration became apparent. Internationally, after the Rio Earth Summit in 1992, there were calls for a shift to a resource-recycling society, and in Europe and the United States, competition to develop plant-derived bioplastics was progressing.

Against this backdrop, Shimadzu Corporation established a plant in Otsu City, Shiga Prefecture, Japan, with an annual production capacity of 100 tons of Lacty® polylactic acid plastic. The raw material is lactic acid extracted from corn and other grains, which does not depend on petroleum resources and is decomposed into water and carbon dioxide by microorganisms and enzymes after use. With its excellent transparency and safety, it was expected to be applied to medical sutures, drug delivery systems, and food packaging materials.

Related key technologies are the improvement of lactic acid fermentation efficiency, removal of impurities in the purification process, and polymerization technology through polycondensation. In addition, copolymerization and blending technologies to compensate for the brittleness of polylactic acid, as well as optimization of molding processes, were also advanced. At the time, PHA resins derived from microbial fermentation and aliphatic polyester biodegradable resins were also being developed, and Shimadzu's efforts were a pioneering example in Japan.

The plant, located in Otsu City, Shiga Prefecture, which is home to Lake Biwa and has a high awareness of water environment conservation, is a symbol of the combination of regional characteristics and corporate environmental technology, and was the first step in the spread of plant-derived plastics in Japan.