Fuser members overcoated with fluorocarbon elastomer containing aluminum oxide

Abstract

A fuser member useful for heat-fixing an electrographic toner to a substrate. The fuser member has a core and a layer overlying the core. That layer includes a cured fluorocarbon random copolymer having subunits with the general structures: where x is from 30 to 90 mole percent, y is from 10 to 70 mole percent, and z is from 0 to 34 mole percent. The layer incorporates particulate filler. The filler includes aluminum oxide and a material selected from the group consisting of alkaline earth metal oxides, alkaline earth metal hydroxides, and combinations thereof. The filler has a total concentration in the layer of from about 25 to 50 percent of the total volume of the layer. The aluminum oxide has a concentration of from 20 to 40 percent of the total volume of the layer.

What is claimed is:  
     
       1. A fuser member comprising a core and a layer overlying said core, said layer comprising: a cured fluorocarbon random copolymer comprising subunits having the general structures:                    
       wherein 
       x is from 30 to 90 mole percent,  
       y is from 10 to 70 mole percent, and  
       z is from 0 to 34 mole percent;  
       said layer further comprising particulate filler, said particulate filler including aluminum oxide and a material selected from the group consisting of alkaline earth metal oxides, alkaline earth metal hydroxides, and combinations thereof; said particulate filler having a total concentration in said layer of from about 25 to 50 percent of the total volume of said layer, said aluminum oxide having a concentration of from 20 to 40 percent of the total volume of said layer. 
     
     
       2. The fuser member of  claim 1  wherein said alkaline earth metal hydroxide comprises calcium hydroxide and said alkaline earth metal oxide comprises magnesium oxide. 
     
     
       3. The fuser member of  claim 1  wherein said polymer is nucleophilic addition cured. 
     
     
       4. The fuser member of  claim 1  wherein said polymer is crosslinked by biphenolic residues. 
     
     
       5. The fuser member of  claim 1  wherein x is from 40 to 80 mole percent, y is from 10 to 60 mole percent, and z is from 0 to 34 mole percent. 
     
     
       6. The fuser member of  claim 1  wherein x is from 42 to 75 mole percent, y is from 14 to 58 mole percent, and z is 0. 
     
     
       7. The fuser member of  claim 1  wherein z is 0. 
     
     
       8. The fuser member of  claim 1  wherein x is greater than 40 mole percent. 
     
     
       9. A fuser member useful for heat-fixing an electrographic toner to a substrate, said fuser member comprising: a core, a base cushion superimposed on said core and an outer layer superimposed on said base cushion, said outer layer comprising a bisphenol cured fluorocarbon random copolymer comprising subunits having the general structures:                    
       wherein 
       x, y, and z are selected such that fluorine atoms represent at least 70 percent of the total formula weight of said subunits;  
       said outer layer having filler particles dispersed therein, said filler particles further comprising:  
       particles selected from the group consisting of alkaline earth metal oxides and alkaline earth metal hydroxides in a concentration of from about 5 to 20 percent of the total volume of said outer layer; and  
       aluminum oxide particles in a concentration of from 20 to 40 percent of the total volume of said outer layer.  
     
     
       10. The fuser member of  claim 9 , wherein the concentration of aluminum oxide particles is from 30 to 40 percent of the total volume of said outer layer. 
     
     
       11. The fuser member of  claim 9  wherein said base cushion layer is resistant to cyclic stress induced deformation and hardening. 
     
     
       12. A fuser member useful for heat-fixing an electrographic toner to a substrate, wherein the roll comprises a core, a base cushion layer overlying said core, and an outer layer superimposed on said base cushion, said outer layer comprising a cured fluorocarbon random copolymer comprising subunits having the general structures:                    
       wherein 
       x is from 10 to 90 mole percent,  
       y is from 10 to 70 mole percent, and  
       z is from 0 to 34 mole percent;  
       said outer layer further comprising particulate filler, said particulate filler including aluminum oxide and a material selected from the group consisting of alkaline earth metal oxides, alkaline earth metal hydroxides, and combinations thereof; said particulate filler having a total concentration in said outer layer of from about 25 to 50 percent of the total volume of said outer layer, said aluminum oxide having a concentration of from 20 to 40 percent of the total volume of said outer layer. 
     
     
       13. The fuser member of  claim 12  wherein said base cushion layer is resistant to cyclic stress induced deformation and hardening. 
     
     
       14. A fuser member comprising a core and a layer overlaying said core, said layer comprising: a cured fluorocarbon random copolymer comprising subunits having the general structures:                    
       
         wherein  
       
       
         x is from  30  to  90  mole percent,  
       
       
         y is from  10  to  70  mole percent, and  
       
       
         z is from  0  to  34  mole percent,  
       
       
         said layer further comprising particulate filler, said particulate filler including aluminum oxide and a material selected from the group consisting of alkaline earth metal oxides, alkaline earth metal hydroxides, and combinations thereof; said layer having a thermal conductivity in the range of about  0 . 15  to  0 . 40  BTU/hr·ft·°F.  
       
     
     
       15. The fuser member of  claim 14  wherein said alkaline earth metal hydroxide comprises calcium hydroxide and said alkaline earth metal oxide comprises magnesium oxide.  
     
     
       16. The fuser member of  claim 14  wherein said polymer is nucleophilic addition cured.  
     
     
       17. The fuser member of  claim 14  wherein said polymer is crosslinked by biphenolic residues.  
     
     
       18. The fuser member of  claim 14  wherein x is from  40  to  80  mole percent, y is from  10  to  60  mole percent, and z is from  0  to  34  mole percent.  
     
     
       19. The fuser member of  claim 14  wherein x is from  42  to  75  mole percent, y is from  14  to  58  mole percent, and z is  0 .  
     
     
       20. The fuser member of  claim 14  wherein z is  0 .  
     
     
       21. The fuser member of  claim 14  wherein x is greater than  40  mole percent.  
     
     
       22. A fuser member useful for heat- fixing an electrographic toner to a substrate, said fuser member comprising: a core, a base cushion superimposed on said core and an outer layer superimposed on said base cushion, said outer layer comprising a bisphenol cured fluorocarbon random copolymer comprising subunits having the general structures:                      
       
         wherein  
       
       
         x, y, and z are selected such that fluorine atoms represent at least  70  percent of the total formula weight of said subunits;  
       
       
         said outer layer having filler particles dispersed therein, said filler particles further comprising:  
       
       
         particles selected from the group consisting of alkaline earth metal oxides and alkaline earth metal hydroxides; and  
       
       
         aluminum oxide particles;  
       
       
         said outer layer having a thermal conductivity in the range of about  0 . 15  to  0 . 40  BTU/hr·ft·°F.  
       
     
     
       23. The fuser member of  claim 22  wherein said base cushion layer is resistant to cyclic stress induced deformation and hardening.  
     
     
       24. A fuser member useful for heat- fixing an electrographic toner to a substrate, wherein the roll comprises a core, a base cushion layer overlying said core, and an outer layer superimposed on said base cushion, said outer layer comprising a cured fluorocarbon random copolymer comprising subunits having the general structures: subunits having the general structures:                      
       
         wherein  
       
       
         x is from  10  to  90  mole percent,  
       
       
         y is from  10  to  70  mole percent, and  
       
       
         z is from  0  to  34  mole percent;  
       
       
         said outer layer further comprising particulate filler, said particulate filler including aluminum oxide and a material selected from the group consisting of alkaline earth metal oxides, alkaline earth metal hydroxides, and combinations thereof; and said outer layer having a thermal conductivity in the range of about  0 . 15  to  0 . 40  BTU/hr·ft·°F.  
       
     
     
       25. The fuser member of  claim 24  wherein said base cushion layer is resistant to cyclic stress induced deformation and hardening.  
     
     
       26. A method which comprises using a fuser member according to  claim 1  for heat- fixing a heat - softenable toner material to a substrate.    
     
     
       27. A method which comprises using a fuser member according to  claim 9  for heat- fixing a heat - softenable toner material to a substrate.    
     
     
       28. A method which comprises using a fuser member according to  claim 12  for heat- fixing a heat - softenable toner material to a substrate.    
     
     
       29. A method which comprises using a fuser member according to  claim 14  for heat- fixing a heat - softenable toner material to a substrate.    
     
     
       30. A method which comprises using a fuser member according to  claim 22  for heat- fixing a heat - softenable toner material to a substrate.    
     
     
       31. A method which comprises using a fuser member according to  claim 24  for heat- fixing a heat - softenable toner material to a substrate.