Patent ID: 6180310
Filing Date: 2001-01-30
Classification: B05C,G03G

Abstract:
A process for fabricating an electrophotographic imaging member comprisingproviding a cylindrical member,depositing on the cylindrical member a coating of a first charge transport layer coating solution by dip coating the cylindrical member in a bath of the first charge transport layer coating solution in a dip coating vessel, the first charge transport layer coating solution comprisinga film forming polymer,a charge transport material, andat least one volatile solvent,the first charge transport layer coating solution having a first predetermined viscosity and the solvent having a viscosity less than the first predetermined viscosity,recirculating undeposited first charge transport layer coating solution from the dip coating vessel to a charge transport layer coating solution vessel and back to the dip coating vessel,repeatedly and sequentially depositing on fresh cylindrical members a coating of the recirculating undeposited first charge transport layer coating solution by dip coating the fresh cylindrical members in a bath of the recirculating undeposited first charge transport layer coating solution in the dip coating vessel, recirculating undeposited first charge transport layer coating solution from the dip coating vessel to the charge transport layer coating solution vessel until the first charge transport layer coating solution reaches a second predetermined viscosity that is greater than the first predetermined viscosity,adding a replenishment solvent from a solvent vessel to the recirculating undeposited first charge transport layer coating solution with continuous mixing to form a second charge transport layer coating solution having a viscosity less than the second predetermined viscosity and substantially equal to the first predetermined viscosity,flowing the second charge transport layer coating solution along a tortuous path in a static mixer to form a homogeneous second charge transport layer coating solution,flowing the homogeneous second charge transport layer coating solution from the static mixer into the dip coating vessel while maintaining laminar flow in the homogeneous second charge transport layer coating solution flowing into the dip coating vessel, andrepeatedly and sequentially depositing the stirred second charge transport layer coating solution on additional fresh cylindrical members in the dip coating vessel.