Koken Ltd., together with its subsidiaries, produces and sells occupational personal protective and environment quality improvement equipment in Japan. It operates in Mask-Related Business, Environmental- Related Businesses, and Other Businesses segments. The company offers clean air solutions, including KOACH, a clean zone creator; KOKENLAMINAR, a push-pull ventilation system; and LAMIKOACH, an air ventilation system as contamination source control. It also provides IMADEZE, a copper-based lactate antibacterial agent; masks for medical facilities and general consumers; and functional water production systems, such as electrolyzed water generators, endoscope washers/disinfectors, blood stain washer kits, and portable showers, as well as magnetically treated water. In addition, the company offers respirators for industrial use, including particulate respirators, powered air-purifying respirators, supplied air respirators, chemical cartridge respirators, and gas masks; respirators for general consumers; equipment for accident and disaster countermeasures; and protective clothes, ear plugs, face shields, etc. The company was founded in 1943 and is headquartered in Tokyo, Japan.