Ex Parte Yamadera et al - Page 8

                Appeal 2007-2242                                                                                 
                Application 10/352,997                                                                           
                examples is 6.64% (Lee, p. 9, Table 1, steel #13).  Lee provides little, if any,                 
                motivation to try at least 7.3% Ni.                                                              
                       With respect to Cr, Lee discloses (Lee, p. 4, ll. 41-44; emphasis                         
                added):                                                                                          
                             The Cr is an important element for improving the corrosion                          
                       resistance.  If the content of Cr is less than 22%, the duplex stainless                  
                       steel cannot have the required corrosion resistance.  On the other                        
                       hand, if it exceeds 27%, the precipitation rate of intermetallic                          
                       compounds becomes faster, with the result that the corrosion                              
                       resistance and the impact toughness are decreased.  Therefore, the                        
                       content of Cr should be preferably limited to 22-27%.                                     

                       Applicants claim steel containing “26% or more, but less than 28%”                        
                of Cr (Br. app. A).  None of Lee’s 48 examples contains Cr in an amount of                       
                at least 26% (Lee, pp. 9-11).  In fact, the highest Cr percentage in any                         
                example is 25.55% (Lee, pp. 9-10, Table 1, steel #19, 32, and 42).  Again,                       
                Lee points to a mass percentage different than Applicants’ 26-28%.                               
                       Finally, with respect to N, Lee discloses (Lee, p. 4, ll. 55-59; emphasis                 
                added):                                                                                          
                             The N is a strong austenite stabilizing element, and improves                       
                       the corrosion resistance.  If the content of N is less than 0.13%, the                    
                       duplex stainless steel cannot have the required corrosion resistance,                     
                       and promotes the precipitation of the intermetallic compounds.  On                        
                       the other hand, if the content of N exceeds 0.27%, then the austenite                     
                       phase is too much reinforced, with the result that the hot ductility is                   
                       decreased.  Therefore, the content of N should be preferably limited to                   
                       0.13-0.27%.  However, if the content of S is less than 0.002%, the                        
                       content of N can be increased up to 0.3%.                                                 
                       Applicants claim steel containing “more than 0.3%, but no more than                       
                0.4%” of N (Br. app. A).  Lee teaches that the content of N should be                            
                preferably below 0.27% (Lee, p. 4, ll. 58-59).  If the content of N exceeds                      

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