Ex parte TSUBUKO et al. - Page 3




          Appeal No. 94-2441                                                          
          Application 07/821,314                                                      


               The subject matter on appeal is directed to a liquid                   
          developer for use in electrophotography comprising a toner which            
          is dispersed into an aliphatic hydrocarbon carrier liquid.  The             
          toner is comprised of a colorant and a polyolefin resin.                    
          Importantly, the polyolefin resin is defined as having an acid              
          value of from 5 to 50 and a melt viscosity at 200EC of from 100             
          to 15,000 cps.  When the polyolefin resin component of the toner            
          has an acid value of less than 5, allegedly the toner does not              
          exhibit sufficient adhesiveness.  When the toner component has an           
          acid value of greater than 50, it is said that the toner                    
          particles tend to coagulate and thereby affect the storage                  
          stability (the “preservability”) of the composition.  With                  
          respect to the melt viscosity parameter of the claimed polyolefin           
          resin, appellants indicate (Specification, pages 5 and 6) that              
          when a polyolefin having a melt viscosity of below 100 cps is               
          used, the toner layer permeates through a transfer sheet to the             
          reverse side upon application of heat, thus resulting in images             
          which are fixed to both sides of the transfer sheet.  Further, it           
          is stated that when a polyolefin having a melt viscosity of more            
          than 15,000 cps is employed, the toner cannot be easily melted              
          upon application of heat.  Therefore, it is difficult to fix the            
          toner image to a transfer sheet at a low temperature.  See the              

                                          3                                           





Page:  Previous  1  2  3  4  5  6  7  8  9  Next 

Last modified: November 3, 2007