The bond magnet and bonded magnet

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PROBLEM TO BE SOLVED : To provide a composition for a bonded magnet which can avoid defective moldings due to solidification of the composition before it is filled entirely into a cavity of a mold and has good injection moldability, and a bonded magnet made by molding it. SOLUTION : In a composition for the bonded magnet, in which rare-earth/transition metal base magnetic particles (A) are mixed and dispersed with a resin binder (B), the resin binder (B) is selected from among polymerized fatty acid based polyamide block copolymer (B-1), or polymerized fatty acid base polyether-ester-amide block copolymer (B-2), and its content is made equal to 50% or larger, such that if the temperature of a molten state composition for a bonded magnet is decreased, the difference ΔT between the temperature at which the increasing rate of the viscosity of the composition starts to be larger (solidification start temperature : Ts) and the temperature at which the increasing rate of the viscosity of the composition starts to be smaller (solidification finish temperature : Tf) is made equal to 20°C or higher. COPYRIGHT : (C)2005, JPO&NCIPI