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 the 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 reports to the relevant authorities as required by the REACH Regulation.
We stringently manage chemicals specified in the PRTR Law⁴ and are working to switch to products that do not contain such substances. As a result of the law’s amendment, which greatly changed the range of specified substances, the amount we used in 2023 came to 38,816 kg.

• 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

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

Mie Plant

Starting in April, the Mie plant gradually replaced Noritake Cool NK-88, the grinding fluid used in their grinding processes, with NK-81L. Changing the controlled substance that they used from diethanolamine (13%) to triazine (1.6%) reduced their use of PRTR substances by 820 kg per year.

THK NIIGATA

In March, THK NIIGATA replaced coolants containing PRTR substances in their grinding processes (diethanolamine/2,2’-iminodiethanol) and cutting processes (sulfarized 2,4,4-trimethylpentene) with products that either do not contain such substances or contain them in lower concentrations. This has resulted in a reduction in the amount of PRTR substances they handle from about 4.2 tons to about 0.2 tons.