Toner and image forming method

• US 7,611,813 B2
• Filed: 01/30/2007
• Issued: 11/03/2009
• Est. Priority Date: 11/08/2005
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Komatsu, Nozomu, Tanikawa, Hirohide, Ootsu, Takeshi, Ishigami, Koh, Naka, Takeshi, Okamoto, Naoki, Baba, Yoshinobu, Itakura, Takayuki, Ida, Tetsuya, Umeda, Noriyoshi
• Primary Examiner(s): Chapman; Mark A
• Application Number:
  US11/668,554
• Publication Number:
  US 20070122727A1
• Time in Patent Office: 1,008 Days
• Field of Search: 430/108.3, 430/111.4, 430/110.3, 430/124.1
• US Class Current: 430/108.3
• CPC Class Codes: G03G 13/20 Fixing, e.g. by using heat
• CPC Class Codes: G03G 9/081 by mixing the toner components in a liquefied state; melt kneading; reactive mixing
• CPC Class Codes: G03G 9/0815 Post-treatment
• CPC Class Codes: G03G 9/0819 characterised by the dimensions of the particles
• CPC Class Codes: G03G 9/0821 characterised by physical parameters magnetic parameters G03G9/083
• CPC Class Codes: G03G 9/0827 characterised by their shape, e.g. degree of sphericity
• CPC Class Codes: G03G 9/08711 with esters of acrylic or methacrylic acid
• CPC Class Codes: G03G 9/08755 Polyesters
• CPC Class Codes: G03G 9/08795 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
• CPC Class Codes: G03G 9/09708 Inorganic compounds
• CPC Class Codes: G03G 9/09716 treated with organic compounds

Abstract

Provided a toner including at least: toner particles each containing at least a binder resin, a release agent, and a colorant; and an inorganic fine powder, in which: a degree of aggregation Y1 at a time of compression (200 kpa) of the toner satisfies a relationship of 15≦Y1≦35, and a degree of aggregation Y2 at a time of non-compression of the toner satisfies a relationship of 7≦Y2≦15; and a highest endothermic peak of the toner is present in a temperature range of 30 to 200° C. in an endothermic curve measured with a differential scanning calorimeter (DSC), and a peak temperature Tsc (° C.) of the highest endothermic peak satisfies a relationship of 60≦Tsc≦130.

Claims

1. A toner comprising at least:

toner particles each containing at least a binder resin, a release agent, and a colorant; and

an inorganic fine powder,

wherein;

(i) a degree of aggregation Y1 at a time of compression (200 kPa) of the toner satisfies a relationship of 15≦

Y1≦

35, and a degree of aggregation Y2 at a time of non-compression of the toner satisfies a relationship of 7≦

Y2≦

15; and

(ii) a highest endothermic peak of the toner is present in a temperature range of 30 to 200°

C. in an endothermic curve measured with a differential scanning calorimeter (DSC), and a peak temperature Tsc (°

C.) of the highest endothermic peak satisfies a relationship of 60≦

Tsc≦

130.

2. A toner according to claim 1, wherein:

a weight average particle diameter (D4) of the toner is 3.0 μ

m to 7.0 μ

m; and

when an average circularity of toner having a circle-equivalent diameter of 2.00 μ

m or more is represented by R, an average circularity of toner having a circle-equivalent diameter in a range of 2.00 μ

m or more to less than 3.00 μ

m is represented by r(a), an average circularity of toner having a circle-equivalent diameter in a range of 3.00 μ

m or more to less than 6.92 μ

m is represented by r(b), and an average circularity of toner having a circle-equivalent diameter in a range of 6.92 μ

m or more to less than 12.66 μ

m is represented by r(c), R, r(a), r(b), and r(c) satisfy relationships represented by expressions (1) to (4);

0.940≦

R≦

0.970 

 

Ex. (1)

R−

0.015≦

r(a)≦

R+0.015 

 

Ex. (2)

R−

0.015≦

r(b)≦

R+0.015 

 

Ex. (3)

R−

0.015≦

r(c)≦

R+0.015 

 

Ex. (4).

3. A toner according to claim 1, wherein the inorganic fine powder contains at least an inorganic fine powder (A) having a number average particle diameter of 20 nm or more to less than 300 nm and an inorganic fine powder (B) having a number average particle diameter of 5 nm or more to less than 20 nm, and a surface of at least one of the inorganic fine powder (A) and the inorganic fine powder (B) is treated with silicone oil.

4. An image forming method comprising:

a charging step of charging an image bearing member;

a latent image formation step of forming an electrostatic latent image on the image bearing member charged in the charging step;

a development step of developing the electrostatic latent image formed on the image bearing member with toner to form a toner image;

a transfer step of transferring the toner image on the image bearing member onto a transfer material through an intermediate transfer member; and

a fixation step of fixing the toner image to the transfer material by bringing the toner image into press contact with the transfer material at a fixation nip portion,

wherein;

a contact pressure at the fixation nip portion is 5.0 to 11.0 N/m²; and

the toner comprises the toner according to any one of claims 1 to 3.