PURPOSE: To obtain a rubber magnet, having very low staining properties, which can be used over a wide range covering the field system of all kinds of micromotors, relay magnets and the like by a method wherein the gas in the region pinched by the peaks of the normal hydrocarbon C14H30 and C32H66 on a gas chromatogram, is brought to a fixed quantity or less.
CONSTITUTION: The title rubber magnet consists of magnetic powder, rubber, a dispersant of magnetic powder and an organic peroxide crosslinking agent, and among the gases volatilizing from the surface of the rubber magnet when it is heated up to 115°C, the total weight of the gas in the region pinched by the peaks of the normal hydrocarbon C14H30 and C32H66 on a gas chromatogram is limited to 0.6ppm/min or less per unit weight of the rubber magnet. In this rubber magnet, the composition of volatile gas has low staining properties, and the occurrence of contamination on a brush and a commutator can be prevented substantially even when the rubber magnet is used in a micromotor having high degree of airtightness.
HONDA KATSUSHI
OSHIMA TERUHIKO
YAMANOBE KATSUMI
MABUCHI MOTOR CO
| JPS63284804A | 1988-11-22 |