PURPOSE: To provide black particles having narrow particle size distribution, and uniform shape and size, and usable as pigment, absorbent, filler, electrical conductive material, and especially material for medical diagnostic, by treating particles of acrylonitrile polymer at a specific temperature.
CONSTITUTION: The objective black particles can be produced by oxidizing particles of an acrylonitrile polymer at 150W300°C, and heating the product at ≥450°C. The acrylonitrile polymer may be an acrylonitrile copolymer having an acrylonitrile content of ≥85mol%, preferably ≥90mol%, as wel as the homopolymer of acrylonitrile. The above polymer particles may be produced by emulsion polymerization or suspension polymerization, however, particles produced by precipitation polymerization (preferably precipitation polymerization from ethyl propionate or n-butyl acetate solution) is preferable. The particle diameter is preferably 0.05W10μm.
MIURA KUMIKO
HOSAKA SHUNTARO
| JPS56156213A | 1981-12-02 | |||
| JPS50148292A | 1975-11-27 | |||
| JPS51132193A | 1976-11-17 | |||
| JPS525696A | 1977-01-17 | |||
| JPS5350088A | 1978-05-08 | |||
| JPS4948821A | 1974-05-11 | |||
| JPS522696A | 1977-01-10 |