Developing assembly and image-forming apparatus

An image-forming apparatus comprising an image-bearing member, a charging means which charges the image-bearing member electrostatically, an imagewise-exposure means which forms an electrostatic latent image on the image-bearing member thus charged, and a developing assembly which develops the electrostatic latent image by means of a developer into a visible image;

• said developing assembly comprising:
• i) a developer container which holds therein a developer;
• ii) a developer-carrying member which is rotatably provided at an opening of said developer container to hold thereon the developer and transport the developer to a developing zone;
• iii) a developer layer thickness control member which is disposed in a non-contact state with respect to said developer-carrying member to control a layer thickness of the developer held on the developer-carrying member;
• iv) a magnetic-field formation means which is enclosed inside said developer-carrying member and disposed stationarily with respect to said developer container and which has magnetic poles for simultaneously a) drawing up the developer from said developer container to said developer-carrying member and b) forming a magnetic field for controlling the layer thickness of the developer on said developer-carrying member where said developer-carrying member faces said developer layer thickness control member;
• and
• v) an agitation means which agitates the developer held in said developer container,
• wherein the developer is a two-component developer which contains wax-dispersed non-magnetic toner particles and a magnetic carrier, said wax-dispersed, non-magnetic toner particles contain at least a binder resin, a colorant, an organometallic compound and a wax, and have an average particle diameter in a range of 2 μm to 10 μm,
• wherein said developer-carrying member is a member which has been subjected to surface blasting with spherical particles so as to have a surface having a ten-point average roughness Rz in a range of D/6 to D/2, where D is the average particle diameter of the magnetic carrier, and
• wherein the magnetic carrier has a magnetization intensity in a range of 8 Am2/kg to 50 Am2/kg in a magnetic field of 7.95775 kA/m.