Toyota Develops Cleaner Auto-Body Surface Treatment Agent

Toyota Develops Cleaner Auto-Body Surface Treatment Agent

Toyota Motor Corp. and Nihon Parkerizing Co., a Japanese manufacturer of surface treatment chemicals, have jointly developed an environmentally preferable surface treatment agent for automobile exteriors. According to the companies, the new agent is the world's first of its kind and can significantly reduce the use of harmful metals and eliminate sludge generated from the surface treatment process.

In the vehicle painting process, manufacturers usually use a zinc phosphate pre-treatment agent to ensure good paint adhesion and corrosion resistance. However, zinc phosphate surface treatment agents contain several kinds of metals that are discharged into wastewater when the vehicle parts are rinsed with water after the treatment. Manufacturers are thus required to treat this wastewater at factory sites. In addition, iron phosphate sludge is generated as a by-product and needs to be disposed of in landfills. These requirements are a significant burden to carmakers.

Unlike conventional zinc phosphate agents, the newly-developed pre-treatment agent is completely free from phosphorus, nickel and manganese. Sludge is not generated in the surface treatment process using this innovative agent. Consisting of zirconium compounds, several other less harmful metals and special organic substances, the new agent has successfully achieved the same level of corrosion resistance as zinc phosphate agents. It also exhibits equivalent or better performance in ensuring the adhesion, durability and finish of paints.

Toyota expects this new agent to become the mainstream for surface treatment in the near future, and introduced it into the painting line at its Takaoka Plant in Toyota City, Aichi Prefecture in early January 2006.