An electrostatographic developer mixture comprising finely-divided positively charging toner particles electrostatically clinging to negatively charging carrier particles. The toner particles comprise a resin, a colorant, and a charge inducing material selected from (1) a long chain hydrazinium compound and (2) an alkyl pyridinium compound. The carrier particles comprise core particles having a coating of fused thermoplastic resin particles wherein the carrier particles are prepared by dry-mixing the core particles with thermoplastic resin particles until the resin particles adhere to the core particles. The mixture of core and resin particles are heated to between 320 DEG F. and 650 DEG F. for between 20 and 120 minutes so that the resin particles melt and fuse to the core particles. The developer mixture is employed to develop electrostatic latent images.
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