Liquid electrophotographic developing compositions

摘要

An electrostatic liquid developer for the development of electrostatic charge patterns is provided wherein the said developer comprises an electrically insulating carrier liquid having a dielectric constant of less than 3 and a volume resistivity in excess of 109 Ohm.cm, resin-coated toner particles suspended in said carrier liquid and an alkylated polymer of a heterocyclic N-vinyl monomer. By the presence of the said polymer excellent developers of positive polarity can be obtained.