Toner for electrostatic image development, toner cartridge, process cartridge and image forming apparatus
AssigneeFuji Xerox Co., Ltd.
InventorsTetsuya Taguchi, Motoko Sakai, Jun Igarashi, Masahiro Takagi
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Abstract
The invention provides a toner for electrostatic image development, containing a toner particle and external additive particles adhered to the surface of the toner particle, each of the external additive particles being constituted of plural irreversibly coalesced primary particles.
Claims38
A toner for electrostatic image development, comprising a toner particle and external additive particles adhered to the surface of the toner particle, each of the external additive particles being constituted of a plurality of irreversibly coalesced primary particles, and the shape factor SF2 of the external additive particles, represented by the following formula (1), being in the range from 110 128 to 160:
- [(particle perimeter)2/(particle projected area×4×π)]×100 (1),
- wherein the number-average particle diameter D1 of the primary particles constituting the external additive particle and the number-average long axis diameter D2 of the external additive particle satisfies the relationship represented by the following formula (2):
- 1.5≦D2/D1≦15 (2).
A toner for electrostatic image development, comprising a toner particle and external additive particles adhered to the surface of the surface of the toner particle, each of the external additive particles being constituted of a plurality of irreversibly coalesced organic primary particles or a plurality of irreversibly coalesced inorganic primary particles that are adhered to one another with a binder resin.
A toner for electrostatic image development, wherein the toner is formed by:
- producing external additive particles by irreversibly coalescing a plurality of primary particles, the shape factor SF2 of the external additive particles, represented by the following formula (1), being in the range of from 128 to 160;
- and
- mixing the external additive particles with toner particles so that the external additive particles adhere to the surface of each of the toner particles:
- [(particle perimeter)2/(particle projected area×4×π)]×100 (1),
- wherein the number-average particle diameter D1 of the primary particles constituting the external additive particle and the number-average long axis diameter D2 of the external additive particle satisfies the relationship represented by the following formula (2):
- 1.5≦D2/D1≦15 (2).
A toner for electrostatic image development, the toner comprising a toner particle and 5 to 300 external additive particles adhered to the surface of the toner particle that comprise a plurality of irreversibly coalesced primary particles and have a shape factor SF2 in a range of from 128 to 160, the shape factor SF2 being represented by the following formula (1):
- ((particle perimeter)2/(particle projected area×4×π))×100 (1),
- wherein the number-average particle diameter D1 of the primary particles constituting the external additive particle and the number-average long axis diameter D2 of the external additive particle satisfies the relationship represented by the following formula (2):
- 1.5≦D2/D1≦15 (2).
Dependencies are inferred from the claim text.