IP Library › Granted Patent US 11,537,057
Granted Patent B2
US 11,537,057 · App. 16/841,731 · Granted Dec 27, 2022

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

Inventors: Toyoshi Sawada (Shizuoka, JP); Kazumi Suzuki (Shizuoka, JP); Katsunori Kurose (Shizuoka, JP); Akihiro Kaneko (Shizuoka, JP)
Assignee: RICOH COMPANY, LTD.
G03G9/08791G03G9/08782G03G15/0822G03G15/1625G03G15/1635G03G15/20
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Quick Facts
Patent No.
US 11,537,057
App. No.
16/841,731
Granted
Dec 27, 2022
Kind
B2
Abstract

A toner is provided. The toner comprises a maleic-acid-modified polyolefin having a polypropylene block in a main chain and having a weight average molecular weight of 60,000 or more.

Claims (21)

1. An image forming method, comprising:

forming an electrostatic latent image on an electrostatic latent image bearer;

developing the electrostatic latent image formed on the electrostatic latent image bearer with a developer containing a toner comprising a maleic-acid-modified polyolefin having a polypropylene block in a main chain and having a weight average molecular weight of 60,000 or more and having a maleic acid modification rate of from 0.5% to 8.0% by mass and wherein the toner is colorless or white, to form a first toner image;

transferring the first toner image formed on the electrostatic latent image onto a recording medium which comprises a plastic film; and

fixing the first toner image on the recording medium,

wherein the first toner image formed in the developing is closer to the recording medium than any other toner images that are present, and

wherein the method further comprises forming a second toner image with any of a black toner, cyan toner, magenta toner, or yellow toner on the first toner image.

2. The image forming method according to claim 1 , wherein the weight average molecular weight is 80,000 or more.

3. The image forming method according to claim 1 , wherein the maleic-acid-modified polyolefin has a ½ outflow temperature of from 95 to 150 degrees C.

4. The image forming method according to claim 1 , wherein the toner further comprises an ester wax.

5. The image forming method according to claim 1 , wherein the toner has a ½ outflow temperature of from 100 to 115 degrees C.

6. The image forming method according to claim 1 , wherein the toner comprises 0.1 to 8.0% by mass of the maleic-acid modified polyolefin.

7. The image forming method according to claim 1 , wherein the weight average molecular weight is from 80,000 to 100,000.

8. The image forming method according to claim 4 , wherein the toner comprises 0.1% to 8.0% by mass of the ester wax.

9. The image forming method according to claim 1 , wherein the maleic-acid-modified polyolefin having a polypropylene block also contain a polyethylene block and a polybutene block.

10. The image forming method according to claim 9 , wherein the toner further comprises a polyester resin.

11. The image forming method according to claim 9 , wherein the toner further comprises a white pigment.

12. The image forming method according to claim 9 , having a maleic acid modification rate of from 1.1% to 5.5% by mass.

13. The image forming method according to claim 9 , wherein the toner comprises 0.1% to 8.0% by mass of the ester wax and 0.1 to 8.0% by mass of the maleic-acid modified polyolefin.

14. The image forming method according to claim 1 , wherein the recording medium is a plastic film selected from the group consisting of polyethylene film, polypropylene film, polyethylene terephthalate film, vinyl chloride resin film, polystyrene film, acrylic film, polycarbonate film, polyphenylene sulfide film, fluororesin film, polyetheretherketone film, polyethersulfone film, aramid film, polyimide film, and triacetate film.

15. The method according to claim 1 , wherein the maleic-acid-modified polyolefin having a polypropylene block in the main chain exudes to an interface between the plastic film and the toner, achieving the fixing.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 7, 2020
From: SAWADA, TOYOSHI; SUZUKI, KAZUMI; KUROSE, KATSUNORI; KANEKO, AKIHIRO
To: RICOH COMPANY, LTD.
Reel/Frame 052326/0718 →
Priority Claims (1)
JP JP2019-077945 · Apr 16, 2019 · national
Continuity (1)
Related Publication 20200333720A1 · Oct 22, 2020