摘要:
A developer for developing electrostatic latent images comprises a toner comprising a colorant and a binder resin composed of a non-linear, low melting point polyester resin, inorganic fine powder A having BET specific surface area of 0.5-30 m.sup.2 /g and inorganic fine powder B having BET specific surface area of 40-400 m.sup.2 /g measured by means of nitrogen adsorption.
摘要:
An electrophotographic image forming method according to (I) a so-called simultaneous development and cleaning scheme or cleaner-less scheme is effectively operated by using a specific non-magnetic toner. (II) The non-magnetic toner comprises non-magnetic toner particles having a shape factor SF-1 of 120-160, a shape factor SF-2 of 115-140 and a weight-average particle size of 4-9 .mu.m. (III) The non-magnetic toner further includes inorganic fine particles (a) having a number-average primary particle size of at most 50 nm and spherical fine particles (b) having a number-average primary particle size of 50-1000 nm and a surface area-based sphericity .psi. of 0.91-1.00, respectively externally added to the non-magnetic toner particles.
摘要:
A toner for developing electrostatic latent images with a good combination of fixability, anti-offset characteristic, anti-sticking characteristic and pulverizability is provided as a composition comprising a colorant or magnetic material and a binder resin. The binder resin has 0.1 to 60 wt. % of a chloroform-insoluble or a THF (tetrahydrofuran)-insoluble and a THF-soluble, the THF-soluble providing a molecular weight distribution in the chromatogram of GPC (gel permeation chromatography) thereof such that there are a main peak in the molecular weight range of 1,000 to 25,000 and a sub-peak or shoulder in the molecular weight range of 2,000 to 150,000. The binder resin may suitably be obtained through two polymerization steps including a solution polymerization step and a suspension polymerization step.