Toner and image forming apparatus using the toner
AssigneeRicoh Company, Ltd.
InventorsShigeru Emoto, Hiroshi Yamashita, Naohiro Watanabe, Tsunemi Sugiyama, Hiroshi Yamada, Masami Tomita
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Abstract
A toner composition including toner particles including mother toner particles, which include a binder resin, a colorant and a release agent, and a charge controlling agent which is located on a surface of the mother toner particles and fixed thereon, wherein the toner particles have a spherical degree of from 0.960 to 1.000 and a specific surface area of from 0.70 to 2.5 m2/g. The toner composition optionally includes an external additive which is present on the surface of the toner particles.
Claims21
Toner particles comprising:
- mother toner particles comprising:
- a binder resin;
- a colorant;
- and
- a release agent;
- and
- a charge controlling agent located on a surface of the mother toner particles and fixed thereon,
- wherein
- the toner particles have a spherical degree of from 0.960 to 1.000 and
- a specific surface area of from 0.70 to 2.5 m2/g.
A method for manufacturing toner particles, comprising:
- reacting a prepolymer having an isocyanate group with an amine in an aqueous liquid comprising at least one of an inorganic dispersant and a particulate polymer to perform an elongation reaction and a crosslinking reaction of the prepolymer and to prepare a urea-modified polyester resin;
- dissolving at least the urea-modified polyester resin in an organic solvent to prepare a binder resin solution;
- dispersing at least the binder resin solution, a colorant and a release agent in an aqueous liquid to prepare a dispersion;
- removing at least the organic solvent and aqueous liquid from the dispersion to prepare mother toner particles;
- and
- fixing a charge controlling agent on a surface of the mother toner particles to prepare toner particles,
- wherein the toner particles have a spherical degree of from 0.960 to 1.000 and a specific surface area of from 0.70 to 2.5 m2/g.
A method for manufacturing toner particles, comprising:
- mixing at least a prepolymer having an isocyanate group, an amine, an organic solvent, a release agent and a colorant to prepare a mixture;
- dissolving the mixture in an aqueous liquid to prepare a dispersion;
- reacting the prepolymer with the amine in the dispersion;
- removing at least the organic solvent and aqueous liquid from the dispersion to prepare mother toner particles;
- fixing a charge controlling agent on a surface of the mother toner particles to prepare toner particles,
- wherein the toner particles have a spherical degree of from 0.960 to 1.000 and a specific surface area of from 0.70 to 2.5 m2/g.
An image forming apparatus comprising:
- an image bearing member;
- a charger configured to charge the image bearing member;
- a light irradiator configured to irradiate the image bearing member with light to form a latent image on the image bearing member;
- an image developer configured to develop the latent image with a developer including a toner to form a toner image on the image bearing member;
- a transfer device configured to transfer the toner image on the image bearing member to a receiving material optionally via an intermediate transfer medium;
- and
- a fixer configured to fix the toner image on the receiving material,
- wherein the toner comprises:
- mother toner particles comprising:
- a binder resin,
- a colorant, and
- a release agent;
- and
- a charge controlling agent located on a surface of the mother toner particles and fixed thereon,
- wherein the toner particles have a spherical degree of from 0.960 to 1.000 and a specific surface area of from 0.70 to 2.5 m2/g.
Toner particles comprising:
- mother toner particles comprising:
- a binder resin,
- a colorant, and
- a release agent;
- and
- a charge controlling agent located on a surface of the mother toner particles and fixed thereon;
- wherein the toner particles have a spherical degree of from 0.960 to 1.000 and a specific surface area of from 0.70 to 2.5 m2/g,
- wherein the specific surface area of the toner particles falls within 110% of the specific surface area of the mother toner particles.
Dependencies are inferred from the claim text.