RESIN MAGNET MATERIAL

PURPOSE:To obtain an anisotropic resin magnet with excellent magnetic characteristics by mixing ferrite powder composed of a mixture of ferrite fine powder of average particle diameter 0.5-1.5mum and ferrite coarse powder of average particle diameter 30-250mum and synthetic resin. CONSTITUTION:Hard ferrite powder, such as barium ferrite and strontium ferrite, and their mixture are used as ferrite powder. Powder of average particle diameter 0.5-1.5mum is usually used as fine powder and especially a single magnetic domain particle is preferable. Powder of average particle diameter 30- 250mum is usually used as coarse powder and especially a multiple magnetic domain particle, whose average diameter is 100-200mum and which is oriented to one direction, is preferable. The mixing ratio of the fine powder and the coarse powder is usually in the range of 1:0.4-1:4 by weight ratio but especially the range of 1:0.7-1:1.2 is preferable. 88-96wt% of the ferrite and 12-4wt% of resin are mixed and pellet whose diameter is around 3mm. is obtained.