Electrostatographic magnetic brush imaging process employing carrier beads comprising high purity nickel Patent #: 4018601
ApplicationNo. 05/673320 filed on 04/05/1976
US Classes:430/111.34, Chemically identified elemental magnetic metal or magnetic alloy carrier148/105, Particulate material148/284, Coating composition applied forms oxide coating427/216, Metal base428/403Coated
ExaminersPrimary: Martin, Roland E. Jr.
Assistant: Frenkel, Stuart D.
International ClassG03G 9/107 (20060101)
AbstractMagnetically-responsive electrostatographic nickel carrier particles having semi-conductive and lower triboelectric charging properties are prepared by heat treating nickel particles in an ambient atmosphere as to provide the carrier particles with an oxide coating. More particularly, commercially available nickel particles are placed in a furnace and the particles are heat treated at a temperature of between about 600° C. and about 1,000° C. for a period of time of between about 5 and 10 minutes. When employed with finely-divided toner particles to develop electrostatic latent images in a magnetic-brush development apparatus, the treated carriers have been found to alleviate shorting problems and to provide developed images having lower background densities and higher resolution than prior carrier materials.