Dry toners for use in electrostatic copiers and printers are normally free-flowing powders at room temperatures. They are often formulated to fuse at elevated temperatures as part of the electrostatic printing and copying process. The specific temperature at which fusing takes place has implications of premature change in the physical characteristics of a given toner, defined as blocking or caking. This is undesirable, but can result when the dry toner is subjected to temperatures in the range of its fusing point during conditions of transport, storage, or local handling; as well as to the environmental parameters in a given location after the product is introduced and held for use in the machine reservoir itself.