An image-forming device that is capable of minimizing toner charge deficiency while feeding an adequate amount of toner to an electrostatic toner transport substrate for transporting toner by an EH effect, having a first storage chamber for storing a mixture of toner and a friction-promoting substance;...http://www.google.com.au/patents/US7187892?utm_source=gb-gplus-sharePatent US7187892 - Toner transport device for image-forming device
