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Reduction of substances with an adverse impact on the environment (restrictions on the use of four substances)

Initiatives to reduce substances with an adverse impact on the environment

Since July 2003, the EU directive on end-of-life vehicles has gradually begun to impose restrictions on the use of four substances: lead, mercury, hexavalent chromium, and cadmium. Furthermore, domestically the Japan Automobile Manufacturers Association has announced its voluntary initiative to reduce these four substances.
MMC has been working on initiatives to reduce substances with an adverse impact on the environment in order to reduce the impact of landfills of shredder dust, etc. on the environment. We will continue to actively research and develop alternative technologies and employ alternative materials.

(1) Lead-Free Fuel Tanks

Steel sheets with a molten lead-tin alloy coating were widely used as the steel sheets for fuel tanks, but these sheets contained about 200 grams of lead per vehicle. After making a comprehensive assessment of corrosion resistance, workability, costs, etc., MMC carried out development based on steel sheets with a zinc coating and developed two kinds of lead-free materials with a corrosion resistance performance at least as good as conventional coatings. We have now switched most of our current production models to these materials.
Moreover, in our new models since the Colt, we have introduced a material that eliminates the hexavalent chromium contained in the chromate layer of the coating and we are continuing to expand use of this material.

Development of Lead-Free Steel Sheets for Fuel Tanks

Development of Lead-Free Steel Sheets for Fuel Tanks

(2) Mercury-Free Combination Meters

The Delica D:5 keeps the use of mercury and cadmium in the fluorescent lights for illumination, etc. down to trace amounts, and has made the illumination of the combination meters mercury-free by employing an LED (light-emitting diode) for the backlight.

mercury-free combination meters

mercury-free combination meters

(3) Hexavalent Chromium-Free Surface Finishing

Hexavalent chromium is used as a protective film for components with a zinc coating such as metal components, bolts and nuts, etc. MMC is promoting the use of alternative material for such components, starting from those with good corrosion resistance and tightening torque, etc. that have no problem in usability. We will continue to work toward the complete elimination of hexavalent chromium from our vehicles.

Development of Hexavalent Chromium-Free Surface Finishing

Development of Hexavalent Chromium-Free Surface Finishing

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