Abstract: A composition for developing electrostatic latent images in electrographic printing or copying machinery is provided in which 10% to less than 40% by weight of a carrier having a mean particle diameter of from 10 to 35 .mu.m is blended with a magnetic toner comprising magnetic powder and a resin. Conventional charge control agents, especially metal complexes of azo dyes and Nigrosine dyes should be excluded from the magnetic toner.

Abstract: A composition for developing electrostatic latent images in electrographic printing or copying machinery is provided in which a toner component is blended with 10 to 40% by weight of a carrier. The toner component includes magnetic toner particles each having magnetic powder bound in a resin, and magnetic particles in admixture with the magnetic toner particles, preferably as an external additive in an amount of 0.1 to 10% by weight.

Abstract: A magnetic carrier powder composed essentially of particles of a ferrite having a composition represented by the formula(MO).sub.100-x (Fe.sub.2 O.sub.3).sub.xwhere M is Mg, Mn, Zn, Ni, a combination of Mg in an atomic ratio of at least 0.05 with at least one metal selected from the group consisting of Zn, Cu, Mn and Co, a combination of Mn in an atomic ratio of at least 0.05 with at least one metal selected from the group consisting of Zn, Cu, Mg and Co, or a combination of Ni in an atomic ratio of at least 0.05 with at least one metal selected from the group consisting of Zn, Mg, Mn, Cu and Co, and x is greater than 53 molar %.

Abstract: A magnetic toner or ink is used in an electrophotography. It comprises a resinous component and a magnetic having a spinel structure and having the formula ##EQU1## wherein M represents at least one of Mn, Ni, Co, Mg, Cu, Zn or Cd; and x is in a range of 0.5 to 1 and y is in a range of 0.1 to 0.571.

Abstract: A ferrite powder type magnetic toner used in an electrophotography. It comprises a resinous component and a ferrite having a spinel structure comprising components of iron oxide at a ratio of 99.9 to 51 mole % as Fe.sub.2 O.sub.3 and at least one metal oxide selected from the group consisting of manganese oxide, nickel oxide, cobalt oxide, magnesium oxide, copper oxide, zinc oxide and cadmium oxide at a ratio of 0.1 to 49 mole % as MO wherein M represents Ni, Co, Mg, Cu, Zn or Cd.

Abstract: An electrode for use in electric prevention for corrosion, the electrode comprising a sintered body of a mixture of iron oxide of 90 to 55 mol % in terms of Fe.sub.2 O.sub.3 and a metal oxide of 10 to 45 mol % in terms of MO (M is at least one metal selected from the group consisting of Mn, Ni, Co, Cu and Zn), and a process of electric prevention for corrosion by using said electrode as an anode.

Abstract: A cathodic protection electrode is mounted in an iron bushing by way of a ring of alumina or forsterite, the bushing being mounted in a glass-lined metallic vessel, such as a water heater. The electrode comprises a solid solution of MFe.sub.2 O.sub.4 (wherein M is at least one metal selected from the group consisting of Mn, Ni, Co, Mg, Cu and Zn) of 0.15 to 87.1 mol%, and Fe.sub.3 O.sub.4 of 99.85 to 12.9 mol%.