Patent ID: 7611812

Claim:
A process for controlling the charge of an electrophotographic toner, electrophotographic developer, powder coating material, electret material or a chargeable material in an electrostatic separation process comprising the step of adding at least one charge control agent to the electrophotographic toner, electrophotographic developer, powder coating material electric material or chargeable material, wherein the at least one charge control agent is a layered double hydroxide salt comprising a combination of trivalent and divalent and optionally monovalent metal cations having hydroxyl groups wherein the number of hydroxyl groups in the layered double hydroxide salt is from 1.8 to 2.2 times the sum of all the metal cations wherein the layered double hydroxide salt contains Mg 2+ and Al 3+ , and one or more organic anions A selected from the group consisting of benzilic acid, naphthalenedisulfonic acid, naphthalenedicarboxylic acid, hydroxynaphthoic acid, octanedicarboxylic acid, decanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, hexadecanedicarboxylic acid, octadecanedicarboxylic acid, naphthalenetetracarboxylic acid, sulfosuccinic acid (C 6 -C 20 )-alkyl monoester, sulfosuccinic acid (C 6 -C 22 )-fluoroalkyl monoester, and an anion of a C 12 -C 44 fatty acid.