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US4014856A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid electrophotographic developers

Assignee: Agfa Gevaert NV
•
Filing: 1973-07-05
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Granted: 1977-03-29
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Expires: 1993-07-05
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Abstract

Abstract A liquid toner composition comprising carrier liquid and toner particles for the development of electrostatic charge patterns is described wherein the said liquid comprises (1) a bivalent or trivalent metal salt of an oxyacid derived from phosphorus containing at least one organic residue and (2) one or more members selected from the group consisting of amines, polyurethans and alkylated polymers of a heterocyclic N-vinyl monomer. By means of the materials (1) and (2) the polarity of the toner particles can be controlled to obtain optimum image density and contrast. When carbon blacks are used as toner material it is possible to control the polarity to obtain either positive-working or negative-working toner compositions.

Inventors

  • 👤 Yvan Karel Gilliams
  • 👤 Jozef Leonard Van Engeland
  • 👤 Noel Jozef De Volder

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 13:24
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/135; G03G9/1355; G03G9/13; G03G9/131; G03G9/132

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 97 words
A liquid toner composition for the development of electrostatic charge patterns comprising an electrically insulating carrier liquid having a volume resistivity of at least 10 9 Ohm.cm and a dielectric constant below 3, and a pigment or colouring agent suspended in the said carrier liquid, wherein the said liquid composition comprises dissolved in the carrier liquid (1) a bivalent or trivalent metal salt of an oxyacid derived from phosphorus containing at least one organic residue and (2) one or more members selected from the group consisting of amines, polyurethans and alkylated polymers of a heterocyclic N-vinyl monomer.
Claim 2
Dependent Claim 97 words
A liquid toner composition for the development of electrostatic charge patterns comprising an electrically insulating carrier liquid having a volume resistivity of at least 10 9 Ohm.cm and a dielectric constant below 3, and a pigment or colouring agent suspended in the said carrier liquid, wherein the said liquid composition comprises dissolved in the carrier liquid (1) a bivalent or trivalent metal salt of an oxyacid derived from phosphorus containing at least one organic residue and (2) one or more members selected from the group consisting of amines, polyurethans and alkylated polymers of a heterocyclic N-vinyl monomer.
Claim 3
Dependent Claim 29 words
A liquid toner composition according to claim 1, wherein said oxyacid derived from phosphorus containing an organic residue is a monoester or diester of an oxyacid derived from phosphorus.
Claim 4
Dependent Claim 27 words
A liquid toner composition according to claim 1, wherein said oxyacid derived from phosphorus contains an organic residue having a chain of 10 to 18 carbon atoms.
Claim 5
Dependent Claim 25 words
A liquid toner composition according to claim 1, wherein said metal salt of an oxyacid derived from phosphorus is a zinc salt of mono-2-butyloctyl phosphate.
Claim 6
Dependent Claim 17 words
A liquid toner composition according to claim 1, wherein the said material designated (2) is an amine.
Claim 7
Dependent Claim 17 words
A liquid toner composition according to claim 5, wherein the amine is an aliphatic or alicyclic amine.
Claim 8
Dependent Claim 15 words
A liquid toner composition according to claim 6, wherein the amine is dodecylamine or didodecylamine.
Claim 9
Dependent Claim 16 words
A liquid toner composition according to claim 1, wherein the material designated (2) is a polyurethan.
Claim 10
Dependent Claim 24 words
A liquid toner composition according to claim 8, wherein said polyurethan is a polyurethan alkyd resin prepared from a vegatable oil with a polyisocyanate.
Claim 11
Dependent Claim 22 words
A liquid toner composition according to claim 1, wherein the material designated (2) is an alkylated polymer of a heterocyclic N-vinyl monomer.
Claim 12
Dependent Claim 17 words
A liquid toner composition according to claim 10, wherein said heterocyclic N-vinyl monomer is a N-vinyl lactam.
Claim 13
Dependent Claim 16 words
A liquid toner composition according to claim 11 wherein said N-vinyl lactam is a N-vinyl pyrrolidone.
Claim 14
Dependent Claim 17 words
A liquid toner composition according to claim 1, wherein the pigment or colouring agent is carbon black.
Claim 15
Dependent Claim 16 words
A liquid toner composition according to claim 1, wherein the carrier liquid is an aliphatic hydrocarbon.

References Cited (Backward Citations)

US2877133A Cited
US3084043A Cited
US3383209A Cited
US3301675A Cited
US3542681A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-28 1980-09-27 1981-03-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-28 1984-09-27 1985-03-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-28 1988-09-27 1989-03-29 $7700.00 Window Closed / Lapsed

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