Belt fuser belt

This invention relates to belts used in heat fixing of toner. Such belts typically are moved across a heating element while in contact with paper or other media carrying toner to be fixed into such media by fusing. Such belts desirably have excellent characteristics of heat resistance, heat conductivity, strength with flexibility, and low dielectric constant. This invention comprises a fuser belt () of polyimide incorporating surface-oxidized boron nitride. The resulting enhanced flexibility provides continuing strength without physical damage during use of the belt in a belt fuser while thermal conductivity is preserved. The extent of flexibility enhancement observed is dependent on the degree of oxidation. Therefore, oxidation temperature and time of oxidation are key variables that are used to control the degree of oxidation and thereby the resulting improvement in the flex fatigue.