Ex parte CHIENG et al. - Page 6

          Appeal No. 94-2414                                                           
          Application 07/911,504                                                       

          quantity of organochlorosilane to bond organochlorosilane to the             
          dry gel thus forming a bonded silica gel structure.  Thus, it is             
          questionable whether the claim language “having essentially one              
          form of silanol moiety” which decribes an intermediate structure             
          of an unreacted dry gel constitutes a structural limitation of               
          the claimed gel, which is a bonded gel.  In this regard, see                 
          Colin at page 298 which describes the structure of silica gel                
          after bonding with a monochlorosilane.                                       
               Even assuming that an unreacted dry gel structure “having               
          essentially one form of silanol moiety” survives the bonding step            
          when the silica gel is reacted and bonded with monochlorosilane,             
          it is not apparent that the claimed bonded silica gel product is             
          distinguished from prior art bonded silica gel products as                   
          described or suggested by Colin.  In this regard, in describing              
          prior art techniques appellants explain in their specification at            
          page 13, lines 1-4 that                                                      
                    [D]ilute hydrofluoric acid wash typically is used                  
               to condition silica before bonding stationary phases                    
               thereto.  Such conditioning improves separation                         
               efficiency and sample recovery because the surface                      
               silanols are fully hydroxylated, i.e., form individual                  
               silanol groups (emphasis added).                                        
          Moreover, Colin teaches at page 297 that maximum coverage density            
          of the bonded phase is obtained when a maximum number of “free               
          silanols” are available on the surface of the silica gel.                    

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