Toner for electrophotography, developer using the same, image-forming process cartridge using the same, image-forming apparatus using the same and image-forming process using the same

• US 20060251984A1
• Filed: 07/10/2006
• Published: 11/09/2006
• Est. Priority Date: 03/22/2002
• Status: Active Grant

• Current Assignee: Hiroshi Yamashita, Kenzo Tatsumi
• Original Assignee: Hiroshi Yamashita, Kenzo Tatsumi
• Inventors: Tatsumi, Kenzo, Yamashita, Hiroshi
• Granted Patent: US 7,214,461 B2
• Time in Patent Office: Days
• US Class Current: 430/122.500
• CPC Class Codes: G03G 15/0921 Details concerning the magnetic brush roller structure, e.g. magnet configuration
• CPC Class Codes: G03G 9/0825 characterised by their structure; characterised by non-homogenuous distribution of components microcapsular toners G03G9/093
• CPC Class Codes: G03G 9/097 Plasticisers; Charge controlling agents

Abstract

The toner of the present invention is suitably used in SLIC development system where a liner velocity of a developer-bearing member is 150 to 500 cm/sec. The toner has resin particles containing at least a coloring agent, and a charge controlling agent fine articles, and a ratio M/T of the amount M (% by weight) of an element in the surface of toner particles as determined by X-ray photoelectron spectroscopy (XPS) to the amount T (% by weight) of the element in the entire toner particles of 20 to 500, which element is present only in a charge control agent among components of the toner and is an element belonging to one of the first, second, third, fourth, and fifth periods of the long form of periodic table of elements except hydrogen, carbon, oxygen, and rare gas elements.

Claims

1-16. -16. (canceled)

17. An image-forming process comprising the steps of:

transporting a developer onto a latent electrostatic image support with a development sleeve disposed on an outermost surface of a developer-bearing member; and

subjecting the developer to contact onto a surface of the latent electrostatic image support so as to develop a latent electrostatic image thereon,

wherein the developer bearing member has at least a main magnetic pole for forming magnetic brushes, where the latent electrostatic image support and the development sleeve come to close to each other with the shortest distance,

when the developing sleeve has a point “

A”

on a surface thereof and on a normal based on the main magnetic pole, and has a point “

B”

being 1 mm distant from the point “

A”

in a direction of the normal to the surface thereof, the point “

B”

has an attenuated magnetic flux density of 0 to 40 with respect to a magnetic flux density of 100 on the point “

A,”

a half width of a magnetic flux density distribution curve of the main magnetic pole, is 5°

to 20°

,

the developer is transported at a linear velocity of 150 mm/sec to 500 mm/sec, and

the developer contains a toner which comprises;

a resin particle containing a coloring agent; and

a charge control agent particle, mixed with the resin particle so as to form a toner particle of the toner,

wherein a ratio (M/T) of an amount M (% by weight) of an element in a surface of the toner particle to an amount T (% by weight) of an element in an entire portion of the toner particle is 20 to 500, the element is contained only within the charge control agent particle, and the element is selected from the first period to the fifth period in a long form of periodic table, excluding a hydrogen element, a carbon element, an oxygen element, and rare gas elements,

the resin particle contains a toner compound having at least a binder resin and a coloring agent, the toner compound is one of dispersed and dissolved in an organic solvent so as to form one of a toner compound-dispersed solvent and a toner compound-dissolved solvent, thereafter one of the toner compound dissolved solvent and the toner compound dissolved solvent is dispersed in an aqueous solution so as to form an emulsion, and a solvent of the emulsion is removed so as to form the resin particle.

19. An image-forming process according to claim 17, wherein the developer contains 4% by weight or more of the toner.

20. An image-forming process according to claim 17, wherein the ratio M/T is 40 to 300.

21. An image-forming process according to claim 17, wherein the binder resin is modified polyester.

22. An image-forming process according to claim 21, wherein the modified polyester is a reaction product of polyester prepolymer and amine.

23. An image-forming process according to claim 21, wherein the binder resin further comprises unmodified polyester.

24. An image-forming process according to claim 23, wherein a weight ratio of the modified polyester to the unmodified polyester (the modified polyester/the unmodified polyester) is 5/95 to 80/20.

25. An image-forming process according to claim 17, wherein the binder resin has a glass transition temperature (Tg) of 50°

C. to 70°

C.

18. (canceled)