| 摘要 |
PROBLEM TO BE SOLVED: To provide a composite magnetic material superior in heat resistance, toughness and a magnetic characteristic by mixing specified amounts of magnetic powder in specified aromatic system polyamide resin. SOLUTION: In polyamide, a dicarboxylic acid component unit constituted of terephthalic acid component unit 50-100 mole %, aromatic system dicarboxylic acid component unit 0-50 mole % except for therephthalic acid and/or an aliphatic dicarboxylic acid component unit 0-50 mole % of the number of carbon atoms 4-20, diamine components unit compreaing aliphatic diamine component unit and/or alicylic diamine component unit are set to be a repetitive constitution unit. The compound magnetic material is constituted of 30-50volum% of aromatic system thermoplastic polyamide whose limit viscosity measured in concentrated sulphric acid at 30 deg.C is within the range of 0.1-2.0dl/g and whose melting point exceeds 280 deg.C and of 50-70volume% of magnetic powders. Thus, the magnetic material superior in heat resistance and a mechanical characteristic can be obtained and it can sufficiently be applied to purposes used under a high temperature environment. |
