Toner and method for producing toner

• US 10,012,918 B2
• Filed: 02/14/2017
• Issued: 07/03/2018
• Est. Priority Date: 02/19/2016
• Status: Active Grant

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Ishigami, Koh, Ohtsu, Takeshi, Kamae, Kentaro, Matsuo, Ryuichiro, Iwasaki, Yosuke, Katsumata, Wakiko, Mitsuiki, Kenta, Miura, Masaharu, Mizo, Yuichi
• Primary Examiner(s): Vajda, Peter L
• Application Number:
  US15/431,821
• Publication Number:
  US 20170242355A1
• Time in Patent Office: 504 Days
• CPC Class Codes: G03G 9/08 with toner particles
• CPC Class Codes: G03G 9/0802 Preparation methods
• CPC Class Codes: G03G 9/0806 whereby chemical synthesis of at least one of the toner components takes place
• CPC Class Codes: G03G 9/081 by mixing the toner components in a liquefied state; melt kneading; reactive mixing
• CPC Class Codes: G03G 9/08711 with esters of acrylic or methacrylic acid
• CPC Class Codes: G03G 9/08755 Polyesters
• CPC Class Codes: G03G 9/08782 Waxes
• CPC Class Codes: G03G 9/08795 characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants
• CPC Class Codes: G03G 9/08797 characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature

Abstract

A toner having a toner particle that is produced through a step of melt-kneading a resin composition containing a binder resin, a colorant, a hydrocarbon wax, and a wax dispersing agent, cooling the obtained kneaded material, pulverizing the obtained cooled material, and heat treating the resulting resin particles, wherein the wax dispersing agent is a polymer provided by graft polymerizing a styrene-acrylic polymer onto a polypropylene, the styrene-acrylic polymer is a polymer having a monomer unit derived from a cycloalkyl (meth)acrylate, and specific relationships are satisfied where Mp(p) is the melting point (° C.) of the polypropylene and Mp(w) is the melting point (° C.) of the hydrocarbon wax.

Claims

1. A method of producing a toner, comprising the steps of:

obtaining a kneaded material by melt-kneading a resin composition containing a binder resin, a colorant, a hydrocarbon wax, and a wax dispersing agent;

cooling the kneaded material to obtain a cooled material;

pulverizing the cooled material to obtain a resin particle; and

heat treating the resin particle, wherein

the wax dispersing agent comprises a polymer provided by graft polymerizing a styrene-acrylic polymer onto a polypropylene,

the styrene-acrylic polymer is a polymer having a monomer unit derived from a cyclohexyl methacrylate, and

formula (1) and formula (2) are satisfied where Mp(p) is a melting point (°

C.) of the polypropylene and Mp(w) is a melting point (°

C.) of the hydrocarbon wax;

70≤

Mp(p)≤

90 

 

(1)

|Mp(p)−

Mp(w)|≤

20 

 

(2).

2. The method of producing a toner according to claim 1, wherein the binder resin contains a crystalline polyester resin and an amorphous polyester resin.

3. The method of producing a toner according to claim 2, wherein the crystalline polyester resin is a condensation polymer of an alcohol component containing at least one compound selected from the group consisting of an aliphatic diol having 6 to 12 carbons and a derivative thereof, and a carboxylic acid component containing at least one compound selected from the group consisting of an aliphatic dicarboxylic acid having 6 to 12 carbons and a derivative thereof, and

a content of the crystalline polyester resin is 1.0 to 15.0 mass parts per 100 mass parts of the amorphous polyester resin.

4. The method of producing a toner according to claim 2, wherein the crystalline polyester resin has a molecular chain terminal at which at least one aliphatic compound selected from the group consisting of an aliphatic monocarboxylic acid having 10 to 20 carbons and an aliphatic monoalcohol having 10 to 20 carbons is condensed.