Claims
- 1. An inkjet ink, comprising:
- (a) an aqueous medium,
- (b) a pigment,
- (c) an anionic dispersant, and
- (d) a humectant;
- wherein the dispersant is all alkyl(sulfophenoxy)benzenesulfonic acid or salt of formula (II): ##STR5## wherein one member of the group R1, R2, R3, R4, and R5 is either a sulfonic acid group or its salt;
- wherein one member of the group R6, R7, R8, R9, and R10 is either a sulfonic acid group or its salt;
- wherein one or more members of the group R1, R2, R3, R4, RS, R6, R7, R8, R9, and R10 is an alkyl group having from about 4 to about 20 carbon atoms; and
- wherein the remaining members of the group R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10 are hydrogen atoms;
- wherein the anionic dispersant adheres to a surface of a particle of the pigment and wherein the pigment particles become negatively charged.
- 2. The ink according to claim 1, further comprising additives selected from the group consisting of surfactants, biocides, fungicides, defoamers, corrosion inhibitors, viscosity modifiers, pH buffers, penetrants, sequestering agents, and combinations thereof.
- 3. The ink according to claim 1, wherein the sulfonic acid salt is SO.sub.3 .sup.- M, where M is selected from the group of hydrogen ion, alkali metal ions and ammonium salts NR.sub.4.sup.+ wherein R is H, alkyl, aralkyl, or aryl).
Parent Case Info
This is a continuation of application Ser. No. 08/757,897 filed Nov. 27, 1996 now U.S. Pat. No. 5,725,647.
US Referenced Citations (34)
Foreign Referenced Citations (1)
Number |
Date |
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0 712 912 A2 |
May 1996 |
EPX |
Continuations (1)
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Number |
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Parent |
757897 |
Nov 1996 |
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