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US4971879A Expired / Lapsed US ⏱️ 0.0 years remaining

Polymer for toner, process for preparation thereof and toner composition

Assignee: Mitsubishi Chemical Corp
•
Filing: 1989-05-08
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Granted: 1990-11-20
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Expires: 2009-05-08
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Abstract

Abstract A polymer binder, in which the content of a residual monomer is not more than 200 ppm, generates a smell only to a very slight extent and provides a toner having an improved blocking resistance and resistance against a plasticizer for polyvinyl chloride. The polymer binder is prepared by maintaining a polymer suspension obtained by suspension polymerization at a temperature of not lower than the glass transition temperature of the polymer and distilling water in an amount of 5 to 60% by weight based on the amount of water present at the time of termination of the polymerization.

Inventors

  • 👤 Sadao Kimura
  • 👤 Ryo Funato
  • 👤 Keiji Yoshida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 08:27
CPC Classifications
C; C08; C08F; C08F6/00; C08F6/001; C08F6/003; G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08784; G03G9/08797

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 36 words
A dry toner particle, comprising: 80 to 95 parts by weight of a polymer binder having a residual monomer content of not more than 200 ppm and 5 to 20 parts by weight of a pigment.
Claim 2
Dependent Claim 36 words
A dry toner particle, comprising: 80 to 95 parts by weight of a polymer binder having a residual monomer content of not more than 200 ppm and 5 to 20 parts by weight of a pigment.
Claim 3
Dependent Claim 22 words
The dry toner particle according to claim 1, wherein the polymer binder has a glass transition temperature of 50° to 100° C.
Claim 4
Dependent Claim 53 words
The dry toner particle according to claim 1, wherein the polymer binder is obtained by suspension polymerization of at least one monomer selected from the group consisting of aromatic vinyl compounds, acrylic acid esters, methacrylic acid esters, vinyl esters and vinyl cyanide compounds, or a monomer mixture predominantly composed of said selected monomer.
Claim 5
Dependent Claim 38 words
The dry toner particle according to claim 1, wherein the polymer binder is obtained by suspension polymerization of a monomer mixture predominantly composed of an aromatic vinyl compound with an acrylic acid ester or a methacrylic acid ester.
Claim 6
Dependent Claim 81 words
The dry toner particle according to claim 1, wherein the polymer binder is prepared by maintaining a polymer suspension obtained by suspension polymerization at a temperature of not lower than the glass transition temperature of the polymer, and distilling water in an amount of 5 to 50% by weight based on the amount of water present at the time of termination of the polymerization to reduce the content of a residual monomer in the polymer to not more than 200 ppm.
Claim 7
Dependent Claim 35 words
The dry toner particle according to claim 1, wherein said particle contains a magnetic material in an amount of 40 to 70% by weight based on the total weight of polymer binder and magnetic material.
Claim 8
Dependent Claim 14 words
The dry toner particle of claim 6, wherein said magnetic material is iron powder.
Claim 9
Dependent Claim 38 words
The dry toner particle according to claim 1, wherein said particle further comprises a minor amount of at least one additive selected from the group consisting of charge controlling agents, off set printing aids and surface treating agents.

References Cited (Backward Citations)

US4228273A Cited
US4229569A Cited
US4452977A Cited
US4385171A Cited
US4601968A Cited
US4592990A Cited
US4591629A Cited
US4699976A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-11-19 1994-05-21 1994-11-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-11-19 1998-05-21 1998-11-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-11-19 2002-05-21 2002-11-20 $7700.00 Window Closed / Lapsed

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