Toner, toner stored unit, image forming apparatus, and image forming method

Patent metadata

Field	Value
Publication number	US-10324388-B2
Application number	US-201715456890-A
Country	US
Kind code	B2
Filing date	Mar 13, 2017
Priority date	Mar 18, 2016
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

A toner including base particles and external additives on the base particles, the toner satisfying Conditions 1 and 2 defined in the specification, when a number distribution D of particle diameters of powder particles B generated from one base particle A is calculated from a density a of the base particles A and a density b of the powder particles B, where the base particles A and the powder particles B are deposited on an adhesive area and mica respectively by feeding the toner into a vacuumed space from an inlet, and allowing the toner to crush against a surface of a substrate having the adhesive area composed of a carbon tape, and the mica disposed in a manner that the surface is orthogonal to a direction connecting between center of the vacuumed space and center of the inlet, Powder particles B: particles detached from the base particles.

First claim

What is claimed is:

1. A toner comprising:
base particles; and
external additives deposited on the base particles,
wherein the base particles comprise a binder resin comprising a crystalline polyester resin,
wherein the toner satisfies Conditions 1 and 2 below, when a number distribution D of particle diameters of powder particles B generated from one base particle A is calculated from a density a of the base particles A and a density b of the powder particles B, where the base particles A are deposited on an adhesive area and the powder particles B are deposited on mica by feeding the toner into a vacuumed space from an inlet, and allowing the toner to crush against a surface of a substrate having the adhesive area composed of a carbon tape, and the mica disposed in a manner that the surface is orthogonal to a direction connecting between a center of the vacuumed space and a center of the inlet,
Powder particles B: particles detached from the base particles,
Condition 1: when the number distribution D is presented in a graph by plotting the ranges of the particle diameters by 25 nm on a horizontal axis, and plotting the number of the powder particles B on a vertical axis, a maximum value of the number of the powder particles B lies in any one of the ranges by 25 nm that are a range of greater than 125 nm but 150 nm or smaller, a range of greater than 150 nm but 175 nm or smaller, and a range of greater than 175 nm but 200 nm or smaller,
Condition 2: in the number distribution D, the number of particles having particle diameters of 125 nm or smaller is 30% or less.

2. The toner according to claim 1 ,
wherein the Conditions 1 and 2 are as follows,
Condition 1: when the number distribution D is presented in a graph by plotting the ranges of the particle diameters by 25 nm on a horizontal axis, and plotting the number of the powder particles B on a vertical axis, the maximum value of the number of the powder particles B lies in a range of greater than 125 nm but 150 nm or smaller,
Condition 2: in the number distribution D, the number of particles having particle diameters of 125 nm or smaller is from 3% through 25%.

3. The toner according to claim 1 ,
wherein the Conditions 1 and 2are as follows,
Condition 1: when the number distribution D is presented in a graph by plotting the ranges of the particle diameters by 25 nm on a horizontal axis, and plotting the number of the powder particles B on a vertical axis, the maximum value of the number of the powder particles B lies in a range of greater than 150 nm but 175 nm or smaller,
Condition 2: in the number distribution D, the number of particles having particle diameters of 125 nm or smaller is from 3% through 20%.

4. The toner according to claim 1 ,
wherein the external additives are at least one selected from the group consisting of silica, titania, alumina, a fluorine compound, and resin particles.

5. A powder comprising:
base particles; and
external additives deposited on the base particles,
wherein the base particles comprise a binder resin comprising a crystalline polyester resin,
wherein the powder satisfies Conditions 1 and 2 below, when a number distribution D of particle diameters of powder particles B generated from one base particle A is calculated from a density a of the base particles A and a density b of the powder particles B, where the base particles A are deposited on an adhesive area and the powder particles B are deposited on mica by feeding the powder into a vacuumed space from an inlet, and allowing the powder to crush against a surface of a substrate having the adhesive area composed of a carbon tape, and the mica disposed in a manner that the surface is orthogonal to a direction connecting between a center of the vacuumed space and a center of the inlet,
Powder particles B: particles detached from the base particles,
Condition 1: when the number distribution D is presented in a graph by plotting the ranges of the particle diameters by 25 nm on a horizontal axis, and plotting the number of the powder particles B on a vertical axis, a maximum value of the number of the powder particles B lies in any one of the ranges by 25 nm that are a range of greater than 125 nm but 150 nm or smaller, a range of greater than 150 nm but 175 nm or smaller, and a range of greater than 175 nm but 200 nm or smaller,
Condition 2: in the number distribution D, the number of particles having particle diameters of 125 nm or smaller is 30% or less.

6. A two-component developer comprising:
a carrier; and
the toner according to claim 1 .

7. A toner stored unit comprising:
a unit; and
the toner according to claim 1 stored in the unit.

8. An image forming apparatus comprising:
an electrostatic latent image bearing member;
an electrostatic latent image forming unit configured to form an electrostatic latent image on the electrostatic latent image bearing member;
a developing unit, which includes a toner, and is configured to develop the electrostatic latent image formed on the electrostatic latent image bearing member with the toner to form a toner image;
a transferring unit configured to transfer the toner image formed on the electrostatic latent image bearing member onto a surface of a recording medium; and
a fixing unit configured to fix the toner image transferred on the surface of the recording medium,
wherein the toner is the toner according to claim 1 .

9. An image forming method comprising:
forming an electrostatic latent image on an electrostatic latent image bearing member;
developing the electrostatic latent image formed on the electrostatic latent image bearing member with a toner to form a toner image;
transferring the toner image formed on the electrostatic latent image bearing member onto a surface of a recording medium; and
fixing the toner image transferred on the surface of the recording medium,
wherein the toner is the toner according to claim 1 .

Assignees

• Kabata Toshiyuki
• Bisaiji Takashi
• Koeda Maiko
• Kurose Katsunori
• Ricoh Co Ltd

Inventors

• Kabata Toshiyuki
• Bisaiji Takashi
• Koeda Maiko
• Kurose Katsunori

Classifications

• G03G13/08

  using a solid developer, e.g. powder developer · CPC title

• G03G9/09708

  Inorganic compounds · CPC title

• G03G15/08

  using a solid developer, e.g. powder developer · CPC title

• G03G9/0819 Primary

  characterised by the dimensions of the particles · CPC title

• G03G9/09766

  comprising fluorine · CPC title