Image forming method

An image forming method, comprising the steps of:

• disposing a latent image-bearing member and a toner-carrying member with a prescribed gap therebetween, said toner-carrying member comprising a cylindrical sleeve;
• supplying a magnetic toner onto the cylindrical sleeve, wherein the magnetic toner comprises a binder resin and magnetic powder and is in the form of particles providing a volume-average particle size between 4 microns and 7 microns and having a number-basis distribution and a triboelectric chargeability satisfying the relation of:
• -0. 1(.mu.c/g).times.A-20(.mu.c/g).ltoreq.Q(.mu.c/g) .ltoreq.-0.1(.mu.c/g).times.A-2(.mu.c/g),
• wherein A is a real number in the range of 20-35 denoting a coefficient of variation of a number-basis distribution of particle sizes of the magnetic toner defined by (S/D.sub.1).times.100 wherein S denotes a standard deviation of the number-basis distribution of particle sizes of the magnetic toner and D.sub.1 denotes a number-average particle size of the magnetic toner, and Q denotes a triboelectric charge (.mu.c/g) of the magnetic toner with iron powder;
• triboelectrically charging the magnetic toner to provide the magnetic toner with a negative charge;
• forming an electrostatic latent image on the latent image-bearing member;
• developing the electrostatic latent image with the magnetic toner having a negative triboelectric charge, on the cylindrical sleeve while the cylindrical sleeve is rotated at a peripheral speed of at least 220 mm/sec., thereby forming a toner image;
• and
• transferring the toner image on the latent image-bearing member to a transfer-receiving material.