| 摘要 |
PURPOSE:To prevent a developer from deterioration of its characteristics due to melt adhesion of a toner to a carrier surface and friction breakdown, etc., even in repeated uses for a long period, and to obtain a carrier high in rust resistance and superior in magnetic characteristics and long in life by using an amorphous solid metal powder made of Fe type alloy, Ni type alloy, or Co type alloy as a developer used for a binary magnetic brush development system. CONSTITUTION:The iron type amorphous alloy, such as Fe-B type, Fe-P type, Fe-P-B type, or Fe-Si-B type, as a yielding strength of about 400kg/mm.<2>, small brittleness, and hardness near 1,000HV, and the addition of Cr to the Fe-P alloy abruptly increases anti-corrosiveness. A powder of an amorphous ferromagnetic alloy, such as alloy based on Fe, Ni, or Co, is smallin crystal anisotropy, and in an example of Fe-Co alloy having a compsn. of zero magnetostriction, its coercive force is 1-2mOe, and its effective magnetic permeabilityis 10<5>-10<6>. Such an amorphous solid metal powder is used as a carrier powder. For example, an amorphous metal powder of a mixture os the Fe-P alloy and 8% Cr is used in an amt. of 5wt% of the carrier to prepare a developer together with the toner, thus magnetic characteristics, etc., of the developer. |
