Management and Reduction of Chemical Substances

Activities and Results

Hazardous Material Management Activities

Environmentally hazardous materials are defined as materials that may be harmful to the human body or ecosystems when contained in a product. In principle, we prohibit the use of such materials in our components and raw materials. For hazardous substances that may be present as impurities, we have established tolerances and handle such materials accordingly.
With regard to the Restriction of Hazardous Substances Directive (RoHS)1 and REACH Regulation2 in the EU and the Administrative Measure on the Control of Pollution Caused by Electronic Information Products3 in China, we have adopted our Green Procurement Guidelines at our production facilities in and outside of Japan and provide information necessary to meeting our customers’ requirements. In addition, we submit REACH reports to the relevant authorities as required.
We stringently manage chemicals specified in the PRTR Law4 and are working to switch to products that do not contain such substances. Our goal is to reduce our handling of these chemicals by 3% each year, and we achieved a reduction from last year, going from 37,962 kg in 2020 to 33,950 kg in 2021. Please visit our homepage for details about our initiatives at each production facility.

  • 1 RoHS Directive: Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment
  • 2 REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) Regulation: A regulation that requires almost all chemicals sold in the EU to be evaluated for safety and to be registered
  • 3 Administrative Measure on the Control of Pollution Caused by Electronic Information Products: A law, also called “China RoHS,” that requires disclosure when certain hazardous substances are present in electronic information products and components
  • 4 PRTR Law: The Act on Confirmation, etc. of Release Amounts of Specific Chemical Substances in the Environment and Promotion of Improvements to the Management Thereof
PRTR Substance Amount and Air Emissions
Substance Amount Air
Xylene 1,308 191
Toluene 2,525 458
Ethylbenzene 375 60
Benzene 120 28
Methylnapthalene 26,166 55
Other 3,456 172
Total 33,950 963
  • * Data includes 12 production facilities in Japan: Yamagata, Kofu, Gifu, Mie, Yamaguchi, THK NIIGATA, THK INTECHS (Sendai and Mishima), NIPPON SLIDE, and THK RHYTHM (Hamamatsu, Inasa, and Kyushu).

Efforts at Each Production Facility

Yamagata Plant

The LM Guide washing process in Factory 1 used to employ Asahiklin AK-225, which contains dichloropentafluoropropane (also known as HCFC-225). Due to a change in the law, the manufacture of products containing this substance was banned in 2019. The remaining inventory was used in 2020, but in January 2021, the plant switched to products not made with HCFC-225, thereby reducing the handling of that chemical by 575 kg per year.