Toppan Printing developed a technology to mix tungsten with paper in high density for the first time in the world in cooperation with Kyoto University’s Masahiro Hiraoka. It successfully made paper that can shield radioactivity. Tungsten has the nature to shield radioactivity. The new paper has the same degree of cutoff performance as lead. Unlike lead, it is easy to process and unharmful to human health. The company has already established a mass production system and started to ship samples. It plans to apply the new paper to radiotherapy treatment and working uniforms for decontamination activities.
The company successfully mixed powder tungsten with paper uniformly in papermaking. It increased the ratio of tungsten from 10-20% to 80%. The standard paper size is about 500 mm square and about 0.3 mm thick. A sheet of the new paper can shield 50% of X-ray used in the medical field, and three sheets combined can shield as much X-ray as 0.25 mm thick lead can shield. With the help of Professor Hiraoka, the company confirmed the performance of the new paper. It is priced at 7,000-8,000 yen per 500 mm square.
Toppan Printing's newly-developed paper cable of shielding radioactivity