Designing a sustainable plastic container based on terahertz spectroscopy

As the transition toward a circular economy accelerates, improving the identifiability of transparent post-consumer plastic packaging has become increasingly important. In this context, incorporating material identifiability into product design is an important requirement, particularly from the perspective of automated sorting systems after disposal. This study proposes a design framework for sustainable plastic packaging that explicitly incorporates material identifiability using terahertz (THz) waves. The framework integrates geometric design, consumer requirements, environmental considerations, and material identifiability as a central design objective. Through a case study on transparent soba noodle containers, we developed a proposed container based on this framework and confirmed that it exhibits stable transmittance characteristics, which are expected to contribute to more reliable material identification. In addition, the proposed container maintains usability and transportation efficiency, indicating that improved identifiability may be achieved without sacrificing practical design requirements.