NKK Corporation today strongly refuted a claim of patent infringement and/or breach of contract as filed in the Tokyo District Court by Nippon Steel Corporation (NSC) earlier today.

   The dispute involves NKK's proprietary duplex galvanized steel sheet, called PZB. NKK, which pioneered the development and application of key technologies and concepts of duplex galvanized steel sheet, filed a patent for it more than a year before NSC applied for its own patent.

   Based on NKK's own technical analysis, the company is confident that its manufacture and sale of PZB in no way infringes on NSC's patent.

   NKK's PZB has a surface layer of iron-zinc alloys containing less than 60 wt% iron. Moreover, its structure and composition are totally different from the continuous surface layers of iron-zinc alloys described in the NSC's patent, which contains 60 wt% or more iron. NKK has supplied PZB to several automobile companies in Japan and in other countries for several years, earning acclaim from its customers for the product's high quality.

   NSC's claim that PZB's surface layer contains 60 wt% or more iron is based on the company's own unique method of analysis. In the opinion of NKK, however, this unique method is not an accurate means of quantitatively analyzing PZB's surface layer. NKK has already notified NSC of this fact. According to NKK's own analysis, which uses the Electron Probe Micro Analysis (EPMA) method, a widely acknowledged method of quantitative analysis, the surface layer of PZB contains less than 60 wt% iron.

   NKK has responded sincerely and consistently to NSC since it first received notice of alleged infringement and/or breach of contract this past February. NKK has explained the facts to NSC based on its operational and experimental data and information. NSC, however, rather than producing any objective material or data supporting its contention or refuting NKK's position, has merely repeated its allegations and refused to further clarify its position any further through mutual discussion.

   NKK, which maintains NSC was wrong to file its suit without paying due consideration to the facts, is determined to vigorously defend its position and establish its innocence in the courts.