Ferrite particles for bonded magnets, resin composition for bonded magnets, and molded product using the same

Abstract

According to the present invention, there are provided ferrite particles for bonded magnets and a resin composition for bonded magnets which are capable of producing a bonded magnet molded product having a good tensile elongation and exhibiting excellent magnetic properties, as well as a bonded magnet molded product such as a rotor which is obtained by using the resin composition. The present invention relates to ferrite particles for bonded magnets having a bulk density of not less than 0.5 g/cm 3 and less than 0.6 g/cm 3 and a degree of compaction of not less than 65%, a resin composition for bonded magnets using the ferrite particles, and a molded product obtained by using the ferrite particles and the resin composition.

1 . Ferrite particles for bonded magnets, having a bulk density of not less than 0.5 g/cm 3  and less than 0.6 g/cm 3  and a degree of compaction of not less than 65%. 
     
     
         2 . The ferrite particles for bonded magnets according to  claim 1 , wherein the ferrite particles have an average particle diameter of 0.9 to 3.0 μm. 
     
     
         3 . The ferrite particles for bonded magnets according to  claim 1 , wherein the ferrite particles are magnetoplumbite-type ferrite particles. 
     
     
         4 . A resin composition for bonded magnets, comprising 83 to 93% by weight of the ferrite particles for bonded magnets as claimed in  claim 1 , and 7 to 17% by weight of an organic binder component. 
     
     
         5 . A molded product comprising the ferrite particles for bonded magnets as claimed in  claim 1 . 
     
     
         6 . The molded product according to  claim 5 , wherein the molded product is a rotor.