公开(公告)号：US4798778A

公开(公告)日：1989-01-17

申请号：US80669

申请日：1987-08-03

Applicant: El-Sayed Lyla M. ,  Steven P. Schmidt ,  Torence J. Trout ,  Robert D. Mitchell

Inventor： El-Sayed Lyla M. ,  Steven P. Schmidt ,  Torence J. Trout ,  Robert D. Mitchell

IPC: G03G9/13 ,  G03G9/12

CPC classification number: G03G9/131

Abstract: A positive-working liquid electrostatic developer consisting essentially of(A) nonpolar liquid having a Kauri-butanol value of less than 30, present in major amount;(B) thermoplastic resin of an ethylene homopolymer or copolymer of ethylene and at least one other monomer, the resin having as a substituent thereon an ester, ester having substitutents, e.g., hydroxyl, carboxyl, amine, alkyl; an amide, amide having substituents, e.g., hydroxyl, carboxyl, amine, alkyl; or acid halide of a carboxylic acid, the resin being in particulate form having an average particle size by area of less than 10 .mu.m; and(C) nonpolar liquid soluble ionic or zwitterionic compound.Several procedures can be used to prepare the developer, e.g., using toner concentrate, modifying a thermoplastic resin before developer is prepared. Pigments and adjuvants can be present in the developer which is useful in copying, making proofs including digital proofs, lithographic printing plates and resists.