Resin-bonded magnet
AssigneeSumitomo Metal Mining Co., Ltd.
InventorsShinichi Hayashi, Shoichi Yoshizawa
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Abstract
A resin-bonded type magnet molded from a composition comprising a magnetic powder and a resin powder in which a resin binder comprises at least one unsaturated polyester resin cured product as the main ingredient. The resin binder contains a peroxide or a reaction product thereof capable of curing at a temperature of 150° C. or lower, and an anisotropic magnetic field of the magnetic powder is 50 kOe or more, and 50% by weight or more of the particles of magnetic powder has a grain size of 100 μm or less. The resin-bonded type magnet is obtained by molding by an injection molding process, an injection molding, a compression process, an injection compression molding process, an injection pressing molding process, or a transfer molding process.
Claims6
A resin-bonded type magnet prepared by molding a composition comprising a magnetic powder and resin binder using injection molding, injection compression molding or transfer molding, said magnet powder having an anisotropic magnetic field (HA) of 50 KOe or more, and said resin binder including at least one unsaturated polyester resin hardened material as a major component and containing a peroxide, or a reaction product thereof, that can be hardened at a temperature of 150° C. or lower said composition having a viscosity at a molding temperature, as measured by a rotational viscometer, in a mixed and conditioned state before adding the magnetic powder, of from 100 mPa·s to 5,000 mPa·s.
Dependencies are inferred from the claim text.