Method for producing toner for developing electrostatic images

Patent metadata

Field	Value
Publication number	US-10409182-B2
Application number	US-201715434430-A
Country	US
Kind code	B2
Filing date	Feb 16, 2017
Priority date	Feb 26, 2016
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

A method for efficiently producing a toner for developing electrostatic images, which contains very few coarse particles and having excellent printing characteristics. The method can comprise a sieving step of removing coarse particles from colored resin particles by, using an air flow, supplying the colored resin particles to a sieve, wherein a metal mesh laminate comprising at least two metal meshes attached to each other by sintering, the metal meshes being different in opening size, is used as the sieve; wherein the metal meshes of the metal mesh laminate are laminated in order of opening size and, of the metal meshes constituting the metal mesh laminate, one having a smallest opening size is disposed on a side of supplying the colored resin particles; and wherein the opening size of the metal mesh having the smallest opening size is in a range of from 32 to 110 μm.

First claim

The invention claimed is:

1. A method for producing a toner for developing electrostatic images, the method comprising a sieving step of removing coarse particles from colored resin particles by, using an air flow, supplying the colored resin particles to a sieve,
wherein when the colored resin particles are supplied to the sieve using the air flow, a solid-air ratio of the colored resin particles with respect to the air is set to be in a range of from 0.05 to 0.37 by mass,
wherein a metal mesh laminate comprising at least two metal meshes attached to each other by sintering, the metal meshes being different in opening size, is used as the sieve;
wherein the metal meshes of the metal mesh laminate are laminated in order of opening size and one of the metal meshes having a smallest opening size is disposed on a side of supplying the colored resin particles;
wherein the opening size of the metal mesh having the smallest opening size is in a range of from 32 to 110 μm; and
wherein a ratio of opening sizes of two metal meshes randomly selected from all of the metal meshes constituting the metal mesh laminate, is in a range of from 1.18 to 27 when the ratio of the opening sizes is determined as a ratio of an opening size of a metal mesh having a relatively large opening size with respect to an opening size of a metal mesh having a relatively small opening size.

2. The method for producing the toner for developing electrostatic images according to claim 1 , wherein the opening sizes of all of the metal meshes constituting the metal mesh laminate are in a range of from 32 to 850 μm.

3. The method for producing the toner for developing electrostatic images according to claim 1 , wherein, for all of the metal meshes constituting the metal mesh laminate, longitude lines are at right angles to latitude lines; the longitude lines of all of the metal meshes are disposed approximately parallel to each other; and the latitude lines of all of the metal meshes are disposed approximately parallel to each other.

4. The method for producing the toner for developing electrostatic images according to claim 1 , wherein a volume average particle diameter (Dv) of the colored resin particles supplied to the sieve using the air flow is in a range of from 4 to 11 μm, and a content of coarse particles having a volume average particle diameter (Dv) of 20 μm or more in the colored resin particles, is 0.2% or more by volume.

Assignees

• Zeon Corp

Inventors

• Oyama Fuminari
• Okamoto Nobuhiko
• Toshimitu Hironori
• Izumi Satoshi
• Yasuda Bunta
• Emura Koichi

Classifications

• G03G9/0926

  characterised by physical or chemical properties · CPC title

• B07B1/4663

  Multi-layer screening surfaces · CPC title

• B07B7/06

  by impingement against sieves · CPC title

• B07B1/4618

  Manufacturing of screening surfaces · CPC title

• G03G9/0815 Primary

  Post-treatment · CPC title