weight of distearyl dimethyl ammonium methyl sulfate the toner and carrier particles were mixed in a high intensity lodige blender for about 10 minutes to result in a developer composition comprising about 4 percent by weight of the toner particles and about 96 percent by weight of the carrier particles and exhibiting a tribo product of about 132 both of the above prepared developers were treated according to the paint shaker tone detone surrogate aging method a method designed to simulate the aging process that occurs for developers during normal use in an electrophotographic imaging device specifically the developers were introduced into two separate bottles and the bottles placed in a paint shaker for a ten minute cycle after the ten minute cycle the toner particles were removed from the bottles and new toner particles were mixed with the carrier particles in the bottles the first or control developer was replenished with toner particles identical in composition to those initially present the second or experimental developer was replenished with a mixture of toner particles identical to those initially present in the second developer and toner particles identical to those initially present in the first developer both developers were subjected to a repeated number of ten minute cycles in the paint shaker each developer being detoned and replenished with.