To obtain a composition for bond magnet having excellent fluidity and capable of readily molding even highly filled with magnetic material powder, capable of producing a molded material having high magnetic force and excellent impact resistance, and useful as a magnetic roll material for a dry copying machine, etc., by blending magnetic material powder with a specific polyester.
This composition is obtained by blending (A) magnetic material powder (e.g. a ferrite magnetic material or a rare earth magnetic materials having 0.05-100μm, especially 0.1-10μm average particle diameter) with (B) a polyester (e.g. polyethylene terephthalate resin having 40,000-60,000 number- average molecular weight) obtained by subjecting (B1) a compound of the formula: HO-R1-OH (R1 is a bifunctional 1-5C aliphatic hydrocarbon group) and (B2) a compound of the formula: HOOC-Ar-COOH (Ar is benzene or naphthalene ring) to their polycondensation, preferably in a weight ratio of the components (A/B) of (97/3)-(60/40).
SHINOGAYA TOSHIKAZU
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