Organosol including amphipathic copolymeric binder made with soluble high tg monomer and liquid toners for electrographic applications

摘要

The invention provides liquid toner compositions in which the polymeric binder is chemically grown in the form of copolymeric binder particles dispersed in a liquid carrier. The polymeric binder includes one amphipathic copolymer that comprises the residue of a Soluble High T_g Monomer. The toners described herein exhibit surprisingly low fusion temperatures, yet are surprisingly resistant to blocking, are non-tacky and are resistant to marring and undesired erasure.;Specifically, the present invention provides a liquid electrophotographic toner composition comprising:a) a liquid carrier having a Kauri-Butanol number less than about 30 mL; andb) a plurality of toner particles dispersed in the liquid carrier, wherein the toner particles comprise polymeric binder comprising at least one amphipathic copolymer comprising one or more S material portions and one or more D material portions, wherein one or more of the S or D material portions comprises the residue of a Soluble High T_g Monomer having a T_g at least about 20°C, wherein:the absolute difference in Hildebrand solubility parameters between the Soluble High Tg Monomer and the liquid carrier is less than about 3 MPa^1/2; andthe D portions of the amphipathic copolymer each have a T_g at least about 30°C,    a method of making a liquid electrophotographic toner composition comprising steps of:a) providing a dispersion of amphipathic copolymer in a liquid carrier having a Kauri-Butanol number less than about 30 mL, wherein said amphipathic copolymer comprises one or more S material portions and one or more D material portions, wherein one or more of the S or D material portions comprises the residue of a Soluble High T_g Monomer having a T_g at least about 20°C, wherein:the absolute difference in Hildebrand solubility parameters between theSoluble High T_g Monomer and the liquid carrier is less than about3 MPa^1/2; andthe D portions of the amphipathic copolymer each have a T_g at least about 30°C; andb) mixing the dispersion with one or more ingredients comprising at least one visual enhancement additive under conditions effective to form a plurality of toner particles,    and a method of electrophotographically forming an image on a substrate surface comprising steps of:a) providing a liquid toner composition as hereinbefore defined;b) causing an image comprising the toner particles to be formed on the substrate surface;c) fusing said image on the substrate surface.