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PROBLEM TO BE SOLVED : To provide a bonded magnet composition that has excellent flowability during low-temperature melting, excellent injection molding properties, and excellent magnetic characteristics, and a bonded magnet using the same.
SOLUTION : The bonded magnet composition including rare-earth-transition-metal based magnetic particles (A) and a polymerized fatty-acid based polyamide block copolymer (B) has the following configuration. The polymerized fatty-acid based polyamide block copolymer (B) includes a structure comprising a polymerized fatty-acid residue, mainly composed of a dimer acid, and a polyethylene glycol dialkyl amine residue. A supercooling degree ΔT of a composition expressed by formula (1) of ΔT=Tc(5)-Tc(50) is ≥15°C, where Tc(5), in the formula, is a solidification temperature measured by using a differential scanning calorimetric measuring device in a state that the composition is cooled nearly to a room temperature at -5°C/min after holding the composition for two minutes by increasing the temperature of the composition to 280°C at 20°C/min in a nitrogen air flow while Tc(50) is a solidification temperature measured by setting a cooling speed to -50°C/min.
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