Toner for developing electrostatic image, process-cartridge and image forming method
First Claim
1. A toner for developing an electrostatic image, comprising a composition including:
- polymer components, a colorant, a wax terminally modified with at least one of maleic acid, maleic acid half ester or maleic anhydride and a charge-controlling agent, wherein the polymer components are characterized by(a) containing substantially no THF (tetrahydrofuran)-insoluble content;
(b) containing a THF-soluble content giving a GPC (gel permeation chromatography) chromatogram showing a main peak in a molecular weight region of 3×
103 -3×
104, and a sub-peak or shoulder in a molecular weight region of 1×
105 -3×
106, and(c) including a low-molecular weight polymer component having molecular weights of below 5×
104 on the GPC chromatogram and an acid value AVL, and a high-molecular weight polymer component having molecular weights of at least 5×
104 and an acid value AVH, satisfying AVL >
AVH ; and
the wax has an acid value AVWAX satisfying
space="preserve" listing-type="equation">0.5×
A.sub.VL >
A.sub.VWAX >
0.05×
A.sub.VL,
space="preserve" listing-type="equation">1.5 mgKOH/g≦
A.sub.VWAX ≦
13.0 mgKOH/g.
1 Assignment
0 Petitions
Accused Products
Abstract
A toner for developing an electrostatic image is composed from a composition including: polymer components, a colorant, a wax and a charge-controlling agent. The polymer components are characterized by (a) containing substantially no THF (tetrahydrofuran)-insoluble content; (b) containing a THF-soluble content giving a GPC (gel permeation chromatography) chromatogram showing a main peak in a molecular weight region of 3×103 -3×104, and a sub-peak or shoulder in a molecular weight region of 1×105 -3×106, and (c) including a low-molecular weight polymer component having molecular weights of below 5×104 on the GPC chromatogram and an acid value AVL, and a high-molecular weight polymer component having molecular weights of at least 5×104 and an acid value AVH satisfying AVL >AVH. The wax has an acid value AVWax satisfying AVL >AVWax and AVWax >0 (mgKOH/g). The toner is characterized by a good combination of low-temperature fixability and anti-offset characteristic, a stable chargeability, and freeness from sleeve ghost phenomenon.
55 Citations
41 Claims
-
1. A toner for developing an electrostatic image, comprising a composition including:
- polymer components, a colorant, a wax terminally modified with at least one of maleic acid, maleic acid half ester or maleic anhydride and a charge-controlling agent, wherein the polymer components are characterized by
(a) containing substantially no THF (tetrahydrofuran)-insoluble content; (b) containing a THF-soluble content giving a GPC (gel permeation chromatography) chromatogram showing a main peak in a molecular weight region of 3×
103 -3×
104, and a sub-peak or shoulder in a molecular weight region of 1×
105 -3×
106, and(c) including a low-molecular weight polymer component having molecular weights of below 5×
104 on the GPC chromatogram and an acid value AVL, and a high-molecular weight polymer component having molecular weights of at least 5×
104 and an acid value AVH, satisfying AVL >
AVH ; and
the wax has an acid value AVWAX satisfying
space="preserve" listing-type="equation">0.5×
A.sub.VL >
A.sub.VWAX >
0.05×
A.sub.VL,
space="preserve" listing-type="equation">1.5 mgKOH/g≦
A.sub.VWAX ≦
13.0 mgKOH/g. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35)
- polymer components, a colorant, a wax terminally modified with at least one of maleic acid, maleic acid half ester or maleic anhydride and a charge-controlling agent, wherein the polymer components are characterized by
-
36. An image forming method, comprising:
- forming an electrostatic image on an electrostatic image-bearing member, and developing the electrostatic image with a toner contained in developing means to form a toner image;
wherein the toner comprises polymer components, a colorant, a wax terminally modified with at least one of maleic acid, maleic acid half ester or maleic anhydride and a charge-controlling agent;
the polymer components are characterized by(a) containing substantially no THF (tetrahydrofuran)-insoluble content; (b) containing a THF-soluble content giving a GPC (gel permeation chromatography) chromatogram showing a main peak in a molecular weight region of 3×
103 -3×
104, and a sub-peak or shoulder in a molecular weight region of 1×
105 -3×
106, and(c) including a low-molecular weight polymer component having molecular weights of below 5×
104 on the GPC chromatogram and an acid value AVL, and a high-molecular weight polymer component having molecular weights of at least 5×
104 and an acid value AVH satisfying AVH ≦
AVH ; and
the wax has an acid value AVWAX satisfying
space="preserve" listing-type="equation">0.5×
A.sub.VL >
A.sub.VWAX >
0.05×
A.sub.VLand
space="preserve" listing-type="equation">1.5 mgKOH/g≦
A.sub.VWAX ≦
13.0 mg/KOH/g.37. - View Dependent Claims (37, 38, 39, 40, 41)
- forming an electrostatic image on an electrostatic image-bearing member, and developing the electrostatic image with a toner contained in developing means to form a toner image;
Specification