Patent ID: 7632620

Claim:
A carrier comprised of a core, and thereover a first polymer coating; wherein the first polymer coating comprises a silicone resin dispersed in a copolymer of polymethyl methacrylate and polyurethane, the silicone resin possessing an average diameter of from about 300 to about 3,000 nanometers and having the formula wherein R is alkyl; and over the first polymer coating a second polymer coating selected from the group consisting of polymethyl methacrylate, sodium lauryl sulfate polymethyl methacrylate, a copolymer of methylmethacrylate/dimethyl aminoethyl methacrylate, a copolymer of methylmethacrylate and tertiarybutylaminoethyl methacrylate, a copolymer of methylmethacrylate and diethylaminoethyl methacrylate, a copolymer of methylmethacrylate and diisopropylaminoethyl methacrylate, and a copolymer of methylmethacrylate and an alkylaminoethyl methacrylate; wherein the carrier possesses a triboelectric charge of from about 22 to about 38 microcoulombs per gram and a conductivity of from about 10 −6 to about 10 −11 (ohm-cm) −1 .