Ex parte CHIENG et al. - Page 4




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


               (d) washing said silica gel until the pH of the gel is at               
          least above about 3.                                                         

               38. A silica gel having a specific surface area of between              
          about 200 and 600 m /g, average pore diameters in the range of2                                                         
          about 50 to about 200 Angstroms and a narrow pore diameter                   
          distribution wherein said distribution has a standard deviation              
          in pore diameter less than about 25 percent of the average pore              
          diameter,                                                                    
               wherein said silica gel is produced by a method comprising:             
               (a) mixing a solution of silicon tetrachloride and a water-             
          soluble, non-aqueous solvent with at least a stoichiometric                  
          quantity of water containing fluoride ion to form a reactant                 
          mixture and to hydrolyze the silicon tetrachloride to silica;                
               (b) permitting the silica to gel;                                       
               (c) aging the gel for about 4 hours;                                    
               (d) separately recovering the silica gel from the remainder             
          of the reactant mixture; and                                                 
               (e) washing said silica gel until the pH of the gel is at               
          least above about 3.                                                         


               The references of record relied upon by the examiner are:               
          Jacques et al. (Jacques)      4,504,595            Mar. 12, 1985             
          Hench et al. (Hench)          4,849,378            Jul. 18, 1989             
          Okamura et al. (Okamura)      4,975,405            Dec.  4, 1990             
          Colin et al. (Colin), “Introduction to Reversed-Phase High-                  
          Performance Liquid Chromatography,” Journal of Chromatography,               
          141 (1977), pp. 289-312.                                                     

               The appealed claims stand rejected under 35 U.S.C.  103                
          over Jacques or Okamura in view of Colin and Hench.                          
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