Abstract: A process for producing a developer carrier is disclosed, which comprises heating a carrier composition containing a resin, magnetic particles and a compound having a lower critical surface energy than the resin, to produce a carrier particle having a higher surface concentration of the compound having a lower critical surface energy. A developer carrier having an average particle size of at least about 50 .mu.m and containing a fluorine-containing compound and fine magnetic particles dispersed in a binder resin is also disclosed. The developer carriers according to the invention when used in magnetic brush development provide superior charge generation, extended life and improved image reproduction.

Abstract: A process for producing carriers for a developer is disclosed, which comprises mixing and heating a carrier material containing a binder resin and a magnetic powder, and essentially free of solvent, to obtain a molten dispersion of the magnetic powder in the binder resin; spraying the molten dispersion into liquid droplets; and cooling the droplets to solidify the droplets into carrier particles. The process eliminates the use of solvents and produces carrier particles of superior toughness, surface smoothness, and sphericality.

Abstract: A toner composition for a two-component type developer capable of developing electrostatically charged images formed on a photoreceptor having a surface layer comprising organic substances, wherein the toner composition contains a fatty acid bisamide compound as an external additive.

Abstract: A process and apparatus for automatically weighing and introducing chemicals are intended to automatically weigh the chemicals and introduce the chemicals into a treatment tank; the chemicals are injected into a chemical container and weighted, and then transported to a dissolving tank adjunct to the treatment tank, and then introduced into the dissolving tank. A control means is provided to put under its control the operations of injecting into a chemical container a desired amount of desired chemicals selected from among plural sorts of chemicals and driving a transportments and an introducing means automatically in association with this injecting operation.

Abstract: A carrier for developer is disclosed, which comprises a core having an average particle size of from 50 to 200 .mu.m and comprising fine magnetic particles dispersed in a binder resin and a polymer overcoat having a critical surface tension of from 10 to 25 dyn/cm formed on the surface of the core. The carrier has improved chargeability, high resistance to surface soiling, and high mechanical strength.

Abstract: A toner for development of latent electrostatic images comprising a coloring agent, a binder resin and a fixing aid, said binder resin comprising a polyvalent metal salt (b) of a carboxyl-containing addition polymer (a) which satisfies the following expressions:10.sup.-2 <(N.multidot.Mw)/2<1010.sup.-5 <N<2.times.10.sup.-3wherein N is the number of moles of metal carboxylate ions contained per gram of the polyvalent metal salt (b), and Mw represents the weight average molecular weight of the addition polymer (a),and said fixing aid comprising at least one compound selected from the group consisting of waxes, fatty acid amides and metal soaps.