IP Library › Granted Patent US 7,932,007
Granted Patent B2
US 7,932,007 · App. 11/229,748 · Granted Apr 26, 2011

Toner and method for producing the same, and image-forming method using the same

Assignee: Ricoh Company, Ltd.
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Quick Facts
Patent No.
US 7,932,007
App. No.
11/229,748
Granted
Apr 26, 2011
Kind
B2
Abstract

There are provided: a method for producing a toner containing to granulate a toner and to subjecting the granulated toner to at least washing with an alkali washing solution, in which the total organic carbon amount extractable from the alkali-washed toner is 200 ppm/g or less; a toner comprising polyester in which the total organic carbon amount extractable from the toner is 200 ppm/g or less, under the condition that the toner is subjected to washing with the alkali washing solution before extracting; and an image-forming method using such a toner.

Claims (9)

1. A toner obtainable by a process which comprises granulating an intermediate toner comprising a polyester having a terminal carboxyl group, and subjecting the granulated toner to at least washing with a neutral washing solution and at least one alkali washing solution wherein a total organic carbon (TOC) amount extractable from the final alkali-washed toner is 100 ppm/g or less and TOC neutral amount <TOC alkali amount, and

wherein alkali washing is carried out such that the pH of the washing solution after washing is 6.0 to 11.0, and at a temperature such that the toner does not melt or particles thereof do not attach to each other, and for a time period such that the polyester does not induce a hydrolysis reaction.

2. The toner according to claim 1 , wherein the intermediate toner is formed by the process comprising:

allowing an active hydrogen group-containing compound and a polymer capable of reacting with an active hydrogen group-containing compound to react in an aqueous medium so as to form particles containing an adhesive-base material.

3. The toner according to claim 1 , further comprising a crystalline polyester.

4. The toner according to claim 3 , wherein the crystalline polyester has a DSC endothermic peak temperature of 50° C. to 150° C.

5. The toner according to claim 1 , further comprising resin particles.

6. The toner according to claim 5 , wherein the resin particles are formed of at least one resin selected from a vinyl resin, a polyurethane resin, an epoxy resin, and a polyester resin.

7. The toner according to claim 1 , wherein the polyester has an acid value of 5 mg KOH/g to 50 mg KOH/g.

Assignments (2)
CORRECTIVE ASSIGNMENT TO CORRECT THE FIRST ASSIGNORS NAME PREVIOUSLY RECORDED ON REEL 017339 FRANE 0558. Recorded Apr 18, 2006
From: YAMASHITA, HIROSHI; TANAKA, CHIAKI; WATANABE, YOHICHIROH; SUGIYAMA, TSUNEMI; OHKI, MASAHIRO; MATSUOKA, SONOH; YAMADA, MASAHIDE; WATANABE, NAOHIRO; SAITOH, AKINORI; INOUE, RYOTA
To: RICOH COMPANY, LTD.
Reel/Frame 017806/0924 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 12, 2005
From: YAMASHITA, HIROSHITA; TANAKA, CHIAKI; WATANABE, YOHICHIROH; SUGIYAMA, TSUNEMI; OHKI, MASAHIRO; MATSUOKA, SONOH; YAMADA, MASAHIDE; WATANABE, NAOHIRO; SAITOH, AKINORI; INOUE, RYOTA
To: RICOH COMPANY, LTD.
Reel/Frame 017339/0558 →
Priority Claims (1)
JP 2004-273063 · Sep 21, 2004 · national
Continuity (1)
Related Publication 20060068312A1 · Mar 30, 2006