Abstract: Method for forming a toner image on a photosensitive material bearing an electrostatic latent image comprising(a) introducing a one component developer consisting of fine toner particles, said toner particles comprising ferromagnetic powder dispersed in a resin such that at least a portion of said ferromagnetic powder is not totally encased by said resin, said toner particles being capable of accepting a triboelectric charge and having a specific resistivity of 10.sup.14 ohm.

Abstract: Method and apparatus for developing electrostatic latent images comprising a developer which in turn is composed of a toner made up of resin and particles of magnetic materials having negative triboelectricity with respect to the resin dispersed in said resin. The developer is fed to a surface having magnets associated therewith for causing the developer to rise from the magnets in ear-like fashion to brush and deposit the developer on the latent image carrying surface.

Abstract: An image-forming method using a developer comprising as the main component ferromagnetic and insulating toner particles. Said method comprises the steps of holding said developer on a delivery member by a magnetic force, causing the developer to tuft at the developing position and to fall in contact with an electrostatic latent image-supporting member, developing the electrostatic latent image and forming a toner image by the toner particles charged predominantly by mutual friction of the toner particles, and transferring the toner image onto a plain paper superposed on the electrostatic latent image-supporting member by electrostatic transfer means. Said developer has a specific resistance of at least 10.sup.14 .OMEGA.-cm and the potential decay ratio of the developed developer is lower than 50% as measured according to the method defined in the specification.

Abstract: An image-forming method using a developer comprising as the main component ferromagnetic and insulating toner particles. Said method comprises the steps of holding said developer on a delivery member by a magnetic force, causing the developer to tuft at the developing position and to fall in contact with an electrostatic latent image-supporting member, developing the electrostatic latent image and forming a toner image by the toner particles charged predominantly by mutual friction of the toner particles, and transferring the toner image onto a plain paper superimposed on the electrostatic latent image-supporting member by electrostatic transfer means. Said developer has a specific resistance of at least 10.sup.14 .OMEGA.-cm and the potential decay ratio of the developed developer is lower than 50% as measured according to the method defined in the specification.