Positively chargeable liq. electrophotographic developer - based on non-aq. resin dispersion stabilised with copolymer of macro:monomer and unsatd. monomer

摘要

Positively chargeable liq. developer for electrophotography contains a non-aq. solvent (I) with a specific resistance of at least 10 power 9 ohm.cm, and dispersed synthetic resin particles (II) contg. a dispersion-stabilising resin (III), which is dissolved or colloidally dispersed in (I). (III) consists mainly of a graft copolymer of (1) macromonomer(s) with Mw = 1 x 10 power 3 to 1 x 10 power 5, obtd. by binding a terminal COOH gp. on the main chain of a polymer, contg. polymer component(s) of formula (IV), to an epoxide cpd. with polymerisable double bond(s), using a quat. ammonium salt as reaction catalyst, and (2) monomer(s) of formula (V): XO and X1 = -COO-, -OCO-, -(CH2)k-OCO-, -(CH2)k-OCO-, -(CH2)k-COO-, -CO-, -CONHCOO-, -CONHCO-, -SO2-, -CO-, -CON(Z1)- or -SO2N(Z1)- or X1 = Phe (Phe = 1,2-, 1,3- or 1,4-phenylene); Z1 = H or hydrocarbyl; k = 1,2 or 3; a1-2 and b1-2 independently = H, halogen, CN, hydrocarbyl, -COO-Z2 or hydrocarbyl--COO-Z2; Z2 = H or (substd.) hydrocarbyl; QO = a 4-22C aliphatic gp.; Q1 = H or a 1-22C aliphatic or 6-12C aromatic gp. USE/ADVANTAGE - Charge control is better than usual. The developer is suitable for developing printing plates. It has good chargeability, dispersion stability, redispersibility and fixability.