Toner and developer compositions with high surface additive loadings

Abstract

An imaging process which comprises the formation of an image on an imaging member, development of the image with a toner comprised of resin, pigment, and surface additives, and wherein the toner surface area coverage is from about 30 to about 80 percent; transferring the image developed to a substrate; and optionally fixing the image thereto.

What is claimed is: 
     
       1. An imaging process which comprises the formation of an image on an imaging member, development of the image with a toner comprised of resin, pigment, and surface additives, and wherein the toner surface area coverage is from about 30 to about 80 percent; transferring the image developed to a substrate; and optionally fixing the image thereto. 
     
     
       2. A process in accordance with claim 1 wherein the surface area coverage is from about 32 to about 40 percent. 
     
     
       3. A process in accordance with claim 1 wherein the developed toner image possesses excellent transfer efficiency to the substrate. 
     
     
       4. A process in accordance with claim 1 wherein the developed toner image possesses excellent transfer efficiency of from about 75 to about 95 percent to the substrate. 
     
     
       5. A process in accordance with claim 1 wherein the developed toner image possesses excellent transfer efficiency to the substrate as a function of the spacing between the imaging member and the substrate. 
     
     
       6. A process in accordance with claim 5 wherein the spacing, or gap is from about 0 to about 100 microns, and image transfer is accomplished by a corotron. 
     
     
       7. A process in accordance with claim 1 wherein the toner size is from about 5 to about 8 microns in average volume diameter, and the spacing, or gap between the imaging member and the substrate is from about 0 to about 25 microns. 
     
     
       8. A process in accordance with claim 1 wherein the toner size is from about 5 to about 8 microns in average volume diameter, the spacing, or gap between the imaging member and the substrate is about 0 microns, and substantially no image deletions result. 
     
     
       9. A process in accordance with claim 6 wherein the average volume diameter of the toner is from about 7 to about 10 microns. 
     
     
       10. A process in accordance with claim 6 wherein the average volume diameter of the toner is 7 microns. 
     
     
       11. A process in accordance with claim 1 wherein the average volume diameter of the toner is 7 microns. 
     
     
       12. A process in accordance with claim 1 wherein the image transferred is substantially free of deletions. 
     
     
       13. A process in accordance with claim 5 wherein the image transferred is substantially free of deletions. 
     
     
       14. A process in accordance with claim 13 wherein the transfer efficiency is from about 75 to about 95 percent, the toner tribo is from about 15 to about 30 microcoulombs per gram, transfer is accomplished by a corotron, and the average volume diameter of the toner is from about 7 to about 10 microns. 
     
     
       15. A process in accordance with claim 1 wherein the resin is selected from the qroup consistinq of styrene acrylates, styrene methacrylates, styrene butadienes, and polyesters. 
     
     
       16. A process in accordance with claim 1 wherein the pigment is selected from the group consisting of carbon black, cyan, magenta, yellow, red, and mixtures thereof. 
     
     
       17. A process in accordance with claim 1 wherein the surface additives are selected from the group consistinq of colloidal silica, metal oxides, and mixtures thereof. 
     
     
       18. A process in accordance with claim 17 wherein the metal oxides are titanium dioxide or tin oxide. 
     
     
       19. A process in accordance with claim 17 wherein the colloidal silica is present in an amount of from about 0.1 to about 3 weight percent. 
     
     
       20. A process in accordance with claim 17 wherein the metal oxide is present in an amount of from about 0.1 to about 0.5 weight. 
     
     
       21. A process in accordance with claim 17 wherein the colloidal silica is present in an amount of about 0.3 weight percent. 
     
     
       22. A process in accordance with claim 17 wherein the metal oxide is present in an amount of about 1.3 weight percent. 
     
     
       23. A process in accordance with claim 17 wherein the silica is present in an amount of about 1.4 weight percent, and the surface area coverage is about 32 percent; the silica is present in an amount of about 0.63 weight percent, and the surface area coverage is about 36 percent; or the metal oxide is titanium present in an amount of about 1.6 weight percent, and wherein the surface area coverage is about 40 percent. 
     
     
       24. A process in accordance with claim 23 wherein image transfer is accomplished by a corotron. 
     
     
       25. A process in accordance with claim 1 wherein the toner further includes a charge additive. 
     
     
       26. A process in accordance with claim 1 wherein the toner further includes a charge additive of distearyl dimethyl ammonium methyl sulfate. 
     
     
       27. A toner comprised of resin, pigment, and surface additives, and wherein the toner surface area coverage is from about 30 to about 80 percent. 
     
     
       28. A toner in accordance with claim 27 wherein the resin is selected from the group consistinq of styrene acrylates, styrene methacrylates, styrene butadienes, and polyesters. 
     
     
       29. A toner in accordance with claim 27 wherein the pigment is selected from the group consisting of carbon black, cyan, magenta, yellow, red, and mixtures thereof. 
     
     
       30. A toner in accordance with claim 27 wherein the surface additives are selected from the group consisting of colloidal silica, metal oxides, and mixtures thereof. 
     
     
       31. A toner in accordance with claim 30 wherein the metal oxides are titanium dioxide or tin oxide present in an amount of from about 0.1 to about 3 weight percent. 
     
     
       32. A developer comprised of the toner of claim 27 and carrier particles. 
     
     
       33. An imaging process which comprises the formation of an image on an organic layered photoconductive imaging member; development of the image with a toner comprised of resin, pigment, and surface additives, and wherein the toner surface area coverage is from about 30 to about 80 percent; transferring the image developed to a substrate with a corotron and fixing the image thereto, the spacing between the imaging member and the substrate is from about 0 to about 25 microns, the toner tribo is from about 15 to about 30 microcoulombs per gram, the average volume diameter of the toner is from about 6 to about 8 microns, and wherein there results excellent transfer efficiency of from about 75 to about 95 percent to the substrate.