CA2187448A1 - Water-based ink compositions and polymers useful for their preparation - Google Patents

Abstract

Water-based, water-fast ink compositions are provided. The compositions contain an aqueous liquid vehicle, a colorant, e.g., a pigment, dye or stain, and a binder material capable of ionically or physically entrapping the selected colorant. Certain novel polymers are provided as well.

Description

w0951277s9 `'~ 21 8 7448 r~ Y160 . ~
WATER-BASED INK COMPOSITIONS AND POLYMERS USEFUL FOR THEIR PREPARATION
Descri~tion Technical Fleld The present invention relates generally to ink compositions, and more particularly relates to novel water-based, water-fast ink compositions. The invention additionally concerns novel polymers useful for formulating the disclosed water-based ink compositions.
Ba-,hu~ u~.d Concern for the environment as well as increasingly stringent regulation of air quality, pollution and hazardous waste has created a need for alternatives to the use of petroleum and petroleum-based products in ink compositions. The primary focus has been on the development of water- and soy-based printing inks.
The major reason for using water-based ink compositions is that because organic solvents are not present except in very small quantities, potential problems such as toxicity, flammability and other hazards are m;n;m;~ed.
The major drawback of the currently available water-based inks, however, is their generally poor water fastness, which limits their utility.
The present invention is addressed to the aforementioned limitation in the art, and provides a water-based ink composition which is also water-fast.

W095127759 ~ P ~ ~ 27 87448 I~ O~I6O
.
That i5, the ink compositions are prepared in water, substantially without toxic and/or hazardous organic solvents, but after printing and drying become insoluble in water and many of the common organic solvents as well.
The novel ink compositions are advantageous in other ways as well. In contrast to many ink compositions of the prior art, the compositions of the invention may be used on a wide variety of substrates, dry quickly after application, and tend not to bleed or smear after drying. In addition, the present ink compositions are generally low in viscosity (and thus relatively easy to work with), display good soak resistance, and have a relatively long shelf life, typically on the order of a year or more.
Traditional water-based inks are based on resin systems which are dispersed in water. Several references describe inks which are based on aqueous vehicles. U. 5 .
Patent No. 5,106,417 to Hauser et al., for example, describes low viscosity aqueous printing ink compositions ba6ed on polyacrylic resins containing carboxyl groups, and which also contain a humectant, pigment and, optionally, a water-dilutable organic solvent. U. S .
Patent No. 5,166,245 to Zuraw et al. describes water-based printing inks made with modif ied rosin grinding resins. U.S. Patent No. 5,242,489 to Schwarz, Jr., et al., describes an ink composition containing a polymeric additive in addition to a colorant and an aqueous liquid vehicle. U.S. Patent No. 5,244,496 to Easton et al.
describes a water-fast ink composition containing an amine, an acrylic emulsion resin binder, a triamine dye, and water. However, the water-based inks fl; F:nl osed in these ref erences do not provide the af orementioned advantages of the invention; primarily, these inks of the prior art are not both water soluble and water-fast.

W0 9s/277S9 ~ ~ i 2 1 8 7 4 4 8 p~ c o 1160 r ~
In addition to the publications cited hereinabove, the following references are of intere6t as they relate to ink compositions based on aqueous liquid vehicles:
U.S. Patent No. 3,951,892 to Drury et al., which describes a fountain ink composition containing an aqueou6 di6per6ion of a styrene polymer and a colorant;
U.S. Patent No. 4,066,585 to Schepp et al., which describes solvent-free printing ink6 for intaglio or flexographic printing ba6ed on synthetic resin6 6uch a6 polyamide6 or polyester amide6, ~nd are 601id at room temperature but u6ed at temperatureR at which the compo6itions melt and flow;
U.S. Patent No. 4,155,768 to Adams et al., which describes an ink composition for use in ink jet comprising an aqueous solution of a water soluble dye in a polyamine, and having a pH of 8 or lower;
U. S . Patent No . 4 ,163, 675 to Hirano et al ., which relates to an ink composition containing water, a water soluble dye, a naphthalene derivative which i5 present at about 0.1 to 10% by weight, and, optionally; a glycol or polyglycol constituent as a moisture-retaining agent;
U. S. Patent No. 4 ,197 ,135 to Bailey et al ., which describes an AlkAl ;nP ink composition stated to be water-fa6t and useful in ink jet printer applications, wherein the composition is an aqueous solution having a pH of 8 or higher, and contains a water soluble dye and a polyamine having seven or more nitrogen atoms per molecule;
U.S. Patent No. 4,365,035 to Zabiak, which describes a water-based ink composition having an acrylic resin, an inorganic pigment, a solvent (e.g., low boiling alcohol, or water-alcohol mixture), a basic _ _u--d r ~, W09~/277s9 - ! C P~ 1160

2.~;g7448 dissolved in the solvent (e.g., ammonium hydroxide), and a plasticizer;
U.s. Patent No. 4,545,818 to Inoue et al., which generally describes a water-based ink composition 5 containing a water soluble or water-dispersible colorant, a hygroscopic wetting agent (e.g., dihydric alcohol, polyhydric alcohol, pyrrolidone or urea), xanthan gum and, optionally, an organic solvent drying agent (e.g., a glycol ether);
U. S . Patent No. 4, 756, 758 to Lent et al., which describes thermochromic jet ink compositions which are formulated to contain two different dyes and having a resin such as a phenolic resin, a solvent liquid carrier system (e.g., based on a lower aliphatic alcohol and a 15 lower aliphatic branched ketone) and, optionally, surfactants, plasticizers or the like, and wherein the compositions have a viscosity from 1. 6 to 7 . 0 centipoises (cP) at 25C, an electrical resistivity from about 50 to 2000 ohm-cm and a sonic velocity from about 1200 to about 1300 meters/second;
U.S. Patent No. 4,791,165 to Bearss et al., which describes a water-fast and lightfast ink composition having a llyyLos~ ic _ ~ (e.g., glycol), water, a polymer blend and a dye;
U. S . Patent No . 4, 883, 714 to Barton et al ., which describes a fle:~Loy~ ~hic printing ink composition containing polyester materials, polyvinyl alcohol and pigment;
U.S. Patent No. 5,108,505 to Moffatt, which describes ink containing a cyclodextrin to 5011~h; 1; ~e a water-insoluble dye in a water-based ink;
U.S. Patent No. 5,162,399 to Sharma et al., which describes a method for making ink millbase using a water-dispersible polyester in combination with an 35 acrylic polymer;

WO 95127759 ~ `` 2 1 8 7 ~ 4 8 p~ C~o ~160 ~ : '. " ! `i, U.S. Patent No. 5,221,334 to Ma et al., which relates to a pigmented ink composition for ink jet printers wherein the composition is formed from an aqueous carrier medium and insoluble colorants dispersed in an AB or BAB block copolymer having a hydrophilic segment;
U.S. Patent No. 5,275,646 to Marshall et al., which relates to ink-jet ink compositions which are stated to be free of volatile solvents and formulated to include a mixture of colorant, a water soluble polar conductive material and liquid phase, and, optionally, stabilizers, surfactants and wetting agents;
U.S. Patent Nos. 5,288,160 to Li et al., which discloses an ink composition having a pH in the range of approximately 8 to 10, and which contains, among other c l~n--P ~s, an acrylic resin and a pigment;
U.S. Patent No. 5,316,575 to Lent et al., which relates tc jet printing ink compositions containing a resin, a colorant, and other optional ^nts, wherein the compositions are stated to be "substantially free of volatile organic c~mronPnts" and, like the ink compositions in U. S . Patent No . 4, 756, 758 to Lent et al.
summarized above, have a viscosity from 1. 6 to 7. 0 cent~roiqpc at 25C, an electrical resistivity from about 50 to 2000 ohm-cm and a sonic velocity from about 1200 to about 13 0 0 meters / second;
European Patent Publication No. 223, 501, which describes a water-based ink compositions containing water and the reaction product of a water soluble polymer such as a polyethylPnp;m;np with a reactive chl ,~ore; and Japan Kokai Publication No. 56147860, which describes inks containing pigments, polymer dispersing agents and 1,3-dimethyl-2-imidazolifl;n~n~ in aqueous media .

W095/27759 ~ S, 2187448 ~ 0~160 .. . --osure of the Inven~ion It is accordingly a primary object of the invention to address the above-mentioned need in the art by providing a novel water-based ink composition which is 5 also water-fast.
It is another object of the invention to provide such a composition using a binder material that serves to entrap the selected colorant and is preferably biocompatible .
It is still another object of the invention to provide such a composition wherein the binder material comprises a single polymeric resin containing both positively and negatively charged species.
It is yet another object of the invention to provide such a composition wherein the binder material comprises two or more species which in combination 5erve to entrap the selected colorant.
It is a further object of the invention to provide such a composition wherein the binder material comprises: ~a) two polymeric species; (b) two - - ic species; or (c) a polymeric and a monomeric species.
It is still a further object of the invention to provide such a composition in the form of a jet printing ink.
It is yet a further object of the invention to provide such a composition in the form of an ink suitable for use with personal computer-associated printers (i.e., "pc printing" compositions).
It is another object of the invention to provide such a composition in the form of a fl~xu~Lel~hic ink .
It is still an additional object of the invention to provide such a composition in the form of a lithographic ink.

W095/27759 ' ~ 21 87448 ~ 0,l60 It i5 yet an additional object of the invention to provide such a composition in the form of a screen printing ink.
It is also an object of the invention to 5 provide novel polymers use~ul in conjunction ~,rith the present water-based, water-fast ink composition.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become 10 apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention .
In a f irst ~ho~ i ~ L, th,e invention relates to a novel ink composition useful in a variety of printing 15 contexts, e.g., it may be used as a jet printing, pc printing, fle:xOyLc~phic, lithographic or screen printing ink. The composition comprises ~ ts which are soluble in water, or readily rendered soluble in water by addition of a suitable reagent. Accordingly the ink 20 formulation may be prepared in water without need for organic solvents, but is insoluble in water after drying on a substrate.
The binder material of the ink formulation may comprise a single polymeric material, two or more 25 polymeric materials in combination, a single ~ ic material, or two or more ic materials in combination, provided that the materials are such that the selected colorant is either ionically or physically Lr ~.p~ed thereby. For example, a Eirst polymeric 30 material bearing negative charges may be used in combination with a second polymeric material bearing positive charges, so as to form a polymeric network in which a colorant having both positive and negative charges is ionically ellL~ ed. Similarly, a first 35 monomeric acidic material, e.g., citric acid or the like, W0 95/27759 ~ ; s t i ,;1~ 2 1 8 7 4 4 8 . ~ " ~, ~ ~ ,160 may be u6ed in combination with a second monomeric basic material, e.g., a simple diamine or triamine, BO as to form a binder material in the form of a network which, similarly, entraps the colorant either ionically, 5 physically, or both.
In another ptnho~ ,, the invention provides novel polymers useful in the present water-based ink compositions. A first group of these resins, designated herein as Group A, contain hydrophobic segments and ionic 10 6egments which are preferably although not nPcPs:5Arily distinct and nonidentical. Group A resins comprise first mer units having the structural formula (I) and second mer units having the structural formula (II) (I) [Z ]m (II) [l 2]n wherein R1 is a hydrophobic moiety, R2 is an ionic group, 30 zl and z2 are linking moieties, and m and n are ; n/lPrPn~Pntly O or l. These resins may contain additional units having the structural formula (III) W095/27759 , i i ~ 21 87448 r~ so~l60 (III) z3 where Z3 provides for intramolecular cross-linking as will be explained below.
A second group of novel polymers includes resins which are structurally distingl~;chAhlp from the aforementioned Group A resins, but are similar insofar as they also include hydrophobic segments and ionic segments. For convenience, these novel polymers are 15 termed Group B resins herein, and may be defined as comprising first mer units having the structural formula (IVa) and/or (IVb) and second mer units containing pendant carboxylic acid, rhr~rh~n;c acid or sulfonic acid groups or sulfonate groups neutralized with ammonia 20 and/or other amine-containing moieties, such second mer units typically having the structural formula (V) ( IVa) --CH2--C
CoOR4a _ g _ WO 9512M59 ~ 2 1 8 7 4 4 8 PCI~US95/04160 (IVb) --CH2--C
CoNHR4b _ o --CH2--CH--~v) (R5) (R6) In formulae tIVa) and (IVb), R3 is IIYIILO~:II or lower alkyl, while R4a and R4b are alkyl, with R4a preferably being lower alkyl. In formula (V), Rs is an anionic species selected frcm the group consisting of 20 carboxylate, phosphate and sulfonate, and R6 i5 a cationic species, typically a quaternary ammonium moiety, e . g ., imidazolyl , NR74+ , or the like , wherein the R7 moieties may be the same or different and are, fcr example, hydrcgen or lower alkyl. R6 may be associated 25 with a polymer; for example, it may represent a nitrogen atom in either the backbone of a polymer or a pendant group o+; a polymer. R6 may also represent a nitrogen atom in a diamine cross-linking group, such that R6 provides for linkage to another segment of the resin in 30 an intramolecularly crosslinked network. As with the former group of resins, this group also can include additional mer units having the structural formula (III).
Group C resins, the third group of novel polymers herein, comprise first mer units having the Wo95/27759 ~ 2 1 8 7448 r~ , 1160 structure (VI ) and second mer units having the structure (VII) and/or (VIIII) (VI) --CH2--CH2--NH--(VII ) --CH2--CHz--NR8 _ (VIII) --CH2--CH(COOH)--10 wherein, in structure (VII), R8 represents ~1ydLO~
alkyl of 3 to 16 carbon atoms, or lower acyl - (C0) -R9 where R9 is lower alkyl.
Group D resins, the fourth group of novel polymers herein, have h~c khon~c containing 15 a polyethylene glycol moiety and mer units having the structures (IX), (X), (XI) or combinations thereof.
(IX) --C--NH--o (X) --C--0~
N
.

Wo 95l27759 ~ 8 7 4 4 8 p~.,~,~ 01160 1l 5 (XI) ~ CH--(CH~)X--(NH)y--C--O

In these structures, R10 is -COOH or -NH2, x is 0 to 4, ~nd y is O or 1. Specif ic examples of such polymers will be detailed below.
The resins of Groups A, B, C and D are novel polymers which f ind utility in a variety of contexts, but have been f ound to be particularly suitable in conjunction with the preparation of water-based inks, such as those provided herein.
~he ink compositions of the invention provide a number of advantages. Specifically, the novel ink compositions:
-may be ~ 2~ ed in water, but are water-fast once applied to a substrate and allowed to dry;
-are ;nrl~l ;hle with respect to other liquids as well, including A lk~l;n~ solutions, detergents, and organic solvents such as alcohols, acetone and toluene;
-may be used on a wide variety of substrates, ~nrl1lrl;n~ cellulosic materials, glass and many types of plastic;
-dry very quickly after application, taking only a few minutes, and tend not to bleed, smear or rub after drying;
-are relatively simple to manufacture;
-display good soak resistance;

wossn77ss ~ t~ 2187448 P~ 1160 -may be readily tailored with respect to variables such as viscosity, surface tension, dielectric constant and color density by varying the amount or type of resin or additives used;
-may also be tailored with respect to end use, i . e ., a6 j et printing inks , pc printing inks , or the like;
-are not flammable;
-are not harmful to the environment; and -are thermally stable up to temperatures of at least about 150C-200C.
It will be appreciated by those skilled in the art that the compositions of the invention may provide for other advantages also, ~PrPnr9;n~ on the exact choice and relative amounts of the - ~nPnts used as well as on the intended use of the compositions.
Modes for Carrvina Out the Invention Defin;tions and Nomenclatllre Before the present _ '-, compositions and methods are ~ closprl and described, it is to be understood that the terminology used herein is f or the purpose of describing particular ' ~;r?~ts only and is not intended to be limiting.
It must be noted that, as used in the specification and the appended claims, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a resin" includes mixtures of resins, reference to "a polymer" includes mixtures of polymers, reference to "a colorant" includes mixtures of two or more colorants, and the like. Also, it should be noted that reference to "a mer unit" having a particular generic structure inc~ P~ reference to two or more mer WO95/27759 ,~ ~r~ jC~ 21~7448 r~"~lo 1160 units which may or may not have the same specific structure .
In this specif ication and in the claims which follow, reference will be made to a number of terms which 5 shall be defined to have the following -n;n~c The term "water-soluble" as used herein to describe the nature of the ink composition prior to drying on a substrate is intended to mean that the composition dissolves virtually completely. Generally, lO this will mean that the solubility of the composition is at least about 0 . 5 mg/ml in water.
The term "water-fast" as used herein to describe the nature of the ink composition after drying on a sub6trate is intended to mean that the dried 15 composition is insoluble (less than about l mg/ml) in water .
The term "biocompatible" to describe the preferred ink compositions of the invention is used to mean that the _ Ls of the compositions do not 20 degrade or otherwise adversely affect biological materials in any significant way.
The term "organic solvent" is used herein in its conventional sense to refer to a liquid organic a I typically a monomeric organic material in the 25 form of a liguid, preferably a relatively nonviscous li~uid, the molecular structure of which contains lL.,ge1l atoms, carbon atoms, and optionally other atoms as well, and which is capable of dissolving solids, gases or liguids. The present ink formulations are 30 "substantially free" of organic solvents, i.e., they contain less than about 5 . 0 wt. % organic solvents, more preferably less than about 3 . 0 wt. ~ organic solvents, and most preferably are completely free of organic solvents.
}~owever, materials classified as organic solvents in this 35 way may be included in the composition in greater W09sl277s9 ` i~ 2187448 .~ C0,l60 quantities if all such solvent present physically interacts with, chemically reacts with, and/or neutralizes the binder material such that it becomes part of the binder/colorant matrix upon drying on a substrate, S so that the p~:S-~ of any such solvent in free, unassociated form is minimal, i.e., within the aforementioned limited ranges.
The term "entrapped" is used herein to refer to the manner in which colorant is bound by the binder material. The colorant may be ionically associated with the binder material (and thus "ionically entrapped" as the term i8 used herein), i . e ., wherein ionizable or ionized species present on the colorant bind to corrPcpAnfl i n~Aj species on the binder material .
Alternatively, the colorant may be "physically ~LLc~y~edll by the binder, i.e., physically retained by a matrix, such as a matrix of two or more polymeric materials. In either case, "entrapment" is such that after the ink composition dries on a substrate, leaching of colorant from the binder material does not occur.
The term "volatile" is used herein to describe certain types of neutralizing agents useful in conjunction with the present ink compositions. The term is used in its conventional sense to refer to a li~uid ~u~ld which readily vaporizes, has a relatively low boiling point or CIlhl i~ninAj temperature at a~ ,' Pric yLas~uLe, and has a relatively high vapor ~Las~uLe at room temperature. Generally, such ~ c will have a boiling point of less than about 20C, preferably less than about 0C, at c-i _ `Aric pressure, and a vapor p~es~uLa of at least about 500 kPa and preferably at least about 750 kPa at room temperature. Examples of particularly preferred "volatile" neutralizing agent are ammonia and methylamine. The term "nonvolatile" as used herein to refer to certain other neutralizing agents is WO 9s/277s9 `~ r? ~ C 2 ~ 8 7 4 4 8 ~ 1160 intended to mean agents which cannot be classif ied a6 "volatile" as just described. Such agents may be liquids or solids. An example of a particularly preferred "nonvolatile" neutralizing agent is imidazole.
The term "hydrophobic" refers to a tendency not to associate with water. The term is used herein to refer to certain substituents in a relative sen6e, i.e., by identifying the substituent R1 as "hydrophobic, " it is meant that R1 is hydrophobic relative to other portions of the molecular structure containing the substituent.
The term "alkyl" as used herein refers to a branched or unbranched saturated hydrocarbon group of 1 to 24 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, octyl, decyl, tetradecyl, hexadecyl, eicosyl, tetracosyl and the like.
Preferred alkyl groups herein contain 1 to 12 carbon atoms. The term "lower alkyl" is intended to mean an alkyl group of one to six carbon atoms, preferably one to f our carbon atoms .
The term "alkoxy" as used herein refers to an alkyl group bound through an oxygen atom, e.g., methoxy, ethoxy, or the like. The term "lower alkoxy" is intended to mean an alkoxy group of one to six carbon atoms, preferably one to four carbon atoms.
The term "alkylene" as used herein refers to a difunctional saturated branched or unbranched hydrocarbon chain containing from 1 to 24 carbon atoms, and includes, for example, methylene (-CH2-), ethylene (-CH2-CH2-), propylene (-CH2-CH2-CH2-), 2-methylpropylene

3 0 [ -CH2 - CH ( CH3 ) - CH2 - ], hexy l ene [ - ( CH2 ) 6 ~ ] and the l ike . "Lower alkylene" refers to an alkylene group of 1 to 6, more preferably 1 to 4, carbon atoms.
The term "acyl" is used herein in its conventional sense to refer to an alkyl group bound through a carbonyl moiety, i.e., -(C0)-R where R is alkyl Wo 95l27759 ~ t-~t 1~ 2 1 8 7 ~ 4 8 r~ , ll60 as defined above. The term "lower acyl" is used to refer to an acyl group wherein "R" is lower alkyl.
"Optional" or "optionally" means that the subsequently described event or circumstance may or may 5 not occur, and that the description ;nr.l~ c instances where said event or circumstance occurs and instances where it~does not. For example, the phrase "optionally substituted heterocyclic group" means that a heterocyclic group may or may not be substituted and that the 10 de6cription includes both unsubstituted heterocyclic groups and heterocyclic groups where there is substitution .
The ~ovel Tnk Compositions:
The aqueous ink compositions of the invention accordingly comprise an aqueous liquid vehicle, an effective amount of a colorant, and a binder material adapted to ionically or physically entrap the colorant.
The binder material may be a single polymer, a mixture of 20 two or more polymers, a mixture of a monomer and a polymer, or a mixture of two or more r I ~.
In one ~ ;r-nt, the binder material is a single polymeric material comprising a resin which is water soluble in its "free" state or which is readily 25 rendered water soluble by admixture with a suitable neutralizing reagent. However, when admixed with water at room temperature, the resin becomes insoluble in water after drying on a substrate. The composition has a pH in the range of approximately 3 to 12.5, preferably in the 30 range of approximately 4 to 9, and most preferably in the range of 5 to 8. Although the ink compositions are primarily useful for ink jet printing, they may be used in a variety of other contexts as well, as will be explained below.

W0 95/27759 ; ~ 2 1 ~ 7 4 ~ 8 ~ 160 Generally, in this PmhQ~ nt, when a single polymeric material is used as the binder material, it i5 preferred that the polymer be provided with acidic or basic groups, pref erably acidic groups, which may be 5 readily neutralized with a suitable neutralizing composition effective to render the polymer water soluble. For example, the polymer may contain carboxylic acid groups which may then be neutralized with a ba6e such as ammonia, a lower alkyl substituted amine, a 10 polymeric amine, a heterocylic amine such as imidazole, or a combination of such reagents. In a particularly preferred Pmhn~;r^nt, neutralization of a polymer bearing acidic groups is f irst conducted with a volatile neutralizing agent effective to produce a solution of approximately 1 to 50 wt.%, more preferably 5 to 30 wt.%, and most preferably 10 to 20 wt. % of the resin in water;
examples of such volatile neutralizing agents are ammonia nnd methylamine . This procedure is then f ollowed by further neutralizing the polymer with a nonvolatile 20 organic base, e.g., imidazole or an alternative amine as described above. The amount and type of nonvolatile organic base is such that the polymer remains in solution upon volatilization of the initial neutralizing agent but which, after the ink composition has been deposited on 25 and allowed to dry on a substrate, does not render the dried deposit soluble when water is applied thereto.
Generally, between about 0. 01% and 100% and preferably between about 10% to 100% of acidic groups will be neutralized. In some cases, however, neutralization will 3 0 not be nprpcc~ry ~ i . e ., when the polymer is water soluble. Further discussion of suitable binder materials is presented in detail hereinbelow.
The aqueous li~auid vehicle will generally be deionized water, although other nonorganic r ~
35 which are either water soluble or water miscible may be W09s~27759 ~ ~ r ~.~ 21 87448 P~ '0~160 included as well. Generally, an inorganic base such as ammonia or an organic amine (e.g., a lower alkyl amine) is added to bring the pH into the desired range. Where a neutralizing composition is used comprising such a reagent, the composition serves a dual purpose, i.e., to render the binder material water soluble and to adjust the pH of the ink composition upward.
The colorant may be any pigment, dye or stain which may be dissolved, dispersed or suspended in the aqueous liquid vehicle and which is effective to provide the dried ink with the desired coIor and color intensity.
Colorants which tend to be immobilized on the selected resin, e.g., through covalent or ionic attachment, are preferred. Such colorants include azo or "direct" dyes as well as dyes containing acidic groups (e.g., carboxylate, phosphonate or sulfonate moieties), basic groups (e.g., amine salts), or both. In any case, the colorant and the binder material should be selected so that in combination, the colorant becomes tulLLc~ed by 2 o the binder .
Specif ic sxamples of suitable colorants include: Dispersol Blue Grains (Zeneca, Inc. ), Duasyn Acid Blue (Hoechst rPl ~nece), Duasyn Direct Turquoise Blue (Hoechst ~Pl~nP~e), Phthalocyanine blue (C.I.
74160), Diane blue (C.I. 21180), Pro-jet Cyan 1 (Zeneca, Inc. ) . Milori blue (an inorganic pigment equivalent to ultramarine) as cyan colorants; Dispersol Red D-B Grains (Zeneca, Inc. ), Brilliant carmine 6B (C. I. 15850), Pro-jet magenta (Zeneca, Inc. ), Brilliant Red F3B-SF (Hoechst C'elAnP~e), Red 3B-SF ~Hoechst rPl i~nP~:P), Acid ~hoA:~m; nP
(Hoechst ~elAnP~e), Quinacridone magenta (C.I. Pigment Red 122) and Thioindigo magenta (C.I. 73310) as magenta colorants; Dispersol Yellow D-7G 200 Grains (Zeneca, Inc. ), Brilliant yellow (Hoechst CP1 ~npce), Pro-jet 35 yellow 1 (Zeneca, Inc.), benzidine yellow (C.I. 21090 and W0 95/27759 ~ h r ;~ ; 2 l 8 7 4 4 8 1~ 160 C.I. 21100) and Hansa Yellow (C.I. 11680) as yellow colorants; organic dyes; and black materials such as carbon black, charcoal and other forms of finely divided carbon, iron oxide, zinc oxide, titanium dioxide, and the 5 like. Specific and preferred black colorants include Acid Black 48 (Aldrich), Direct Black 58756 A (Crompton &
Knowles), BPI Molecular Catalytic Gray (Brain Power), Fasday Cool Gray (Hunter Delator), Dispersol Navy XF
Grains (Zeneca, Inc. ), Dispersol Black CR-N Grains 10 (Zeneca, Inc.), Dispersol Black XF Grains (Zeneca, Inc.), Hostafine Black TS (Hoechst r.ol ;~nP~:P), Hostafine Black T
(Hoechst CDl~n~ce), Duasyn Direct Black (Zeneca), Pro-jet Black 1 (Zeneca, Inc. ) and Pro-jet Fast Black 2 (Zeneca, Inc. ) .
Generally, it is preferred that the colorant be present in an amount ranging f rom about 0 .1 wt . % to about 20 wt.% of the ink composition, more preferably from about 1 wt. % to about 10 wt. % of the ink composition, and most preferably from about 1 wt.% to about 5 wt.% of the 20 ink composition.
The binder material, in a first 'u';~- ~, comprises a single polymeric material. The material may be any one of the abuv~ - Lioned polymers in Groups A, B, C or D, which will be described in further detail in 25 the following section, or it may be a known resin which f~lnrt;nnc: in an equivalent manner, i.e., to entrap the colorant, either physically or through ionic interaction.
Any such resin, also, should be selected such that it is soluble in water or readily rendered soluble in water by 30 addition of a suitable neutralizing agent, but is water-~ast after being applied to a substrate and allowed to dry. Preferably, the resin is also selected such that it is biocompatible.
Commercially available polymeric materials 35 which may be used include, but are not limited to, Wo 95127759 ; ~ ; 2 1 8 7 4 4 8 ~ o ~160 polyethylPnpiminp~ polyvinylpyrrolidone, polyoxazoline, polyvinylpyridine, polyallylamine (inf 311~1;n~ N-alkylated and N,N-dialkylated polyallylamines), polyvinylaziridine, polyimidazole, polylysine, alginic acid, chitin, chitosan, poly(amino and alkylated amino)ethylenes and ethoxylated polyethyl~nPiminP.
In yeneral, the molecular weight of any polymeric material used in the present ink formulations will be between about 300 and 150,000, and preferably between about 300 and 100,000, although smaller and larger molecular species may be used llPrPn~in~ on the application .
As explained above, the binder material can comprise not only a single polymeric material but also a 15 mixture of two or more polymeric materials, pref erably although not necessarily Group A, Il, C or D resins, so as to produce an interpolymer matrix. The only requirement here with respect to the polymers selected and the relative quantities used is that io~nic or physical 20 entrapment of colorant be such that colorant leaching is precluded. In a preferred ~mho~i- L, when a mixture of polymeric materials is used, one polymer has acidic groups, e.g., carboxylic acid groups, and a second polymer has basic groups, e.g., ionized amine moieties.
25 Examples of suitable combinations include, for example, polyethylPnPiminP, N-alkylated polyethylpnpiminp~
polyimidazole or polyvinylpyridine in combination with an acrylate copolymer such as acrylamide acrylic acid, acrylonitrile acrylic acid, styrene acrylic acid, or the 3 0 like .
In another Pmho~l i L, the binder material comprises a mixture of monomeric species which in combination act to ionically or physically entrap the colorant. In such a case, a first monomeric species is 35 used which is acidic, and a second monomeric species is . .

W095l277~9 ~ 1B7~ r~ a.~ 0~l60 used which is basic. Again, the only limitation on the particular species selected is that the combination provide for complete t~ L . L of cclcrant such that there is no leaching after the ink has been applied to and allowed to dry upon a substrate. Preferred acidic materials in this r-~ - ' i r -nt ccntain two or more acidic groups, e.g., citric acid, tartaric acid, glutaric acid, gluconic acid, and benzene tetracarboxylic acid.
Mr~n~ari~l~ may be used, but shculd be combined with di- or polyacids. Similarly, preferred basic materials in this ~hoair L contain two or more basic groups, e.g., rl;Amine~!:, polyamines and the like. Examples of particularly preferred bases include hexamethylene tetraamine, triethylene tetraamine, ethylene diamine, diethylene triamine, tetraethylene pentamine, pentaethylene h~Yslmin~, tris(2-amincethyl)amine, 1,1,4,7,10,10-hexamethyltriethylene tetramine and N-alkylated as well as N,N-dialkylated substituted amines.
If desired, combinations of acids may be used, as may combinations of bases.
Finally, a single polymeric material may be used in con~unction with a single monomeric material, again, with the materials selected such that the two components are together capable of providing a matrix which entraps the colorant. When the polymer contains ncidic groups, the monomeric material will ccntain basic grcups, and vice versa. The polymer can be any one of the resins of Groups A through D, or it may be a functionally equivalent material.
3 0 The ink compositions of the invention may contain other components as well. A preferred additive is urea or an alkyl-substituted urea, which may be substituted for one or more of the abuv~ Lioned bases, or it may be used in conjunction therewith.
Additionally, it may be preferable in some cases to W0 951277S9 ~ ' 2 1 8 7 4 4 8 i ~~ '01160 include a humectant. Suitable humectants include, for example, triacetin, N-methyl-2-pyrrolidone, and glycerol.
It may also be preferable to include anti-foaming agents with certain compositions; examples of suitable anti-5 foaming agents include 1-dodecyl alcohol, Silicon Antifoam 85390 (Fluka), Surfynol DF75 (Air Products), Surfynol DF210 (Air Products), Carboflow 32W (B.F.
Goodrich), Tego Airex 900 (TegoChemie USA~, TegoFoamex 1488 (TegoChemie USA), S; 1 i ennAntifoamer S670 (Wacker) 10 and Foam Blast 338 (Ross Chemicals). Other additives include viscosity modifiers, surface tension control agents such as anionic and nonionic surface active agents, preservatives and biocides. It may also be desirable in some cases to include cross-linking agents 15 such as im;rlA~A~lp~ substituted imidazoles, polyethylPnP;m;n---, polyvinylimidazole, polyvinylpyridine, and polyaminosiloxanes. Finally, it may also be preferred in some cases to include polyethylene glycol (PEG) when the composition is 20 formulated for jet printing. Incorporation of PEG in the present ink formulations lowers surface tension,; ~vt:S
water fastness, and reduces the 1 ;1~P1 ;hnod that the ink will dry on the jet printing nozzle. When PEG is included in the ink formulation, it should represent on 25 the order of 0 .1 to 20 wt. % of the formulation, more preferably 0.1 to 10 wt.% of the formulation, and most preferably approximately 6 . O wt. 9~i .
However, even though the ink composition may contain these additional . 1-ntS, it is strongly 30 preferred that for jet printing inks, the binder, colorant and water that are present should in combination represent at least about 90 wt. % of the composition.
Also, the composition may contain very small amounts of ~ ic organic solvents , e. g ., lower alcohols or the 35 like. Any such solvents should be present in an amount W0 95/27759 ~ ~ L` ~ I~ S 2 1 ~ 7 4 4 8 P~ 60 that i6 less than about 5 wt . %, pref erably less than about 3 wt. %, of the ink composition. However, if a ic solvent is included in the composition which physically interacts or rhPm;r~lly reacts with the binder 5 material so as to form part o~ the binder/colorant matrix which forms the substance of the dried ink composition, somewhat more solvent may be inrl~ ed.
Novel PolYmeric S~ructllres:
As noted above, a number of polymers useful in conjunction with the present ink compositions are new.
The polymers of Groups A and B, as defined above, contain hydrophobic segments and ionic segments which are typically although not nprpcc~rily distinct and 15 nonidentical.
With regard to Group A resins, such polymers contain first mer units having the structural formula (I) and second mer units having the structural formula (II), wherein Rl, R2, zl, z2, m and n are as defined earlier 20 herein.

(I) --CH2--CH--[Z ]m ~4--WO 95/27759 ; ~ h ~ 2 1 8 7 4 4 8 ~ )~ ;.t 11 --CH2--fH--(II) [Z ]n Pre~erably, Rl is a hydrophobic moiety c.,l ert~
from the group consisting of: cyano; lower alkyl esters;
unsubstituted monocyclic five- and six-carbon aromatic moieties; monocyclic five- and six-carbon aromatic moieties substituted with 1 to 4 substituents Ei~ t~d from the group consisting of lower alkyl, lower alkoxy, halogen and nitro; unsubstituted monocyclic f ive- and six-carbon heterocyclic moieties containing 1 to 3 heteroatoms; and monocyclic f ive- and six-carbon heterocyclic moieties containing l to 3 heteroatoms and 1 to 4 substituents selected from the group consisting of lower alkyl, lower alkoxy, halogen and nitro. Examples of particularly preferred groups suitable as R1 include imidazolyl and pyrrolidinyl, either unsubstituted or substituted with one or more substituents , e . g ., carboxylate-, sulfonate- or phosphate-substituted lower alkylene groups, lower alkyl, lower alkoxy, or the like.
R2 represents a salt moiety -W+X~ or Y~Z+ or a zwitterionic specie6 -A+-Ll-B- or -C--L2-D+ wherein W, Z, and D are inrl~rPn~1i ntly either imidazolyl or a quaternary ; ~lm moiety optionally substituted with alkyl groups, preferably lower alkyl groups, and further wherein Z may be a metallic cation such as sodium, lithium, or the like, X, Y, B and C are selected from the group consisting of carboxylate, ph3sphate and sulfonate, and Ll and L2 are alkylene linking moieties. Examples of ionic species include, for example, -Coo~Z+, -P(o)o22~Z2+, -S03 Z+, -NH4+X, -CH2-NR3+X-, and W095/27759 " . ~ J 2~ 87448 r~.,u.. 11~0 ~
.
,3,,R
X /=~ X~

where R is generally hydrogen or lower alkyl, while lO zwitterionic species include, ~or example, /~N~9-CH2CH2CH2So3 The linking group5 zl and z2 are optional, as may be deduced from the definition of the subscripts "m" and "n," i.e., they may be zero or one. If present, zl and z2 are; ntlPrPn~lPntly selected from the group consisting of arylene, optionally containing l to 3 het~lod~ -, C6-ClB aralkylene, Cl-Cl2 alkylene, -CO-, -COO-, -CONH- and -NHCO-. Lower alkylene and amide linkages are particularly preferred.

Such resins may contain two or more different structural units Pn -q~Pd by the genus of formula (I), and/or two or more different structural units Pn~ -~sPd by the genus of formula (II). The resins may also include additional vinyl-based mer units having the 35 structural ~ormula (III) ~ l ~ g ~
WO 95/27759 ; ~ . .`, 2 ~ 8 7 4 4 8 ~"~,~ C~ 1160 --CH--CH--(III) 2 1 3 wherein Z3 i6 a cross-linking moiety promoting lO intramolecular cross-linking of the resin, such that it is bound to another Yinyl unit within the same resinous species. Z3 may be a siloxane or polysiloxane moiety, a silazane or polysilazane moiety, or a diamine -NR-Z4-NR-where, a6 before, R is ~1y~lLoy~11 or lower allcyl and Z4 is 15 an optional linking moiety, typically lower alkylene.
Examples of speci~ic such resins include the f ollowing:
t(CH2CH)6 (CH2CH) (CH2CH)~
~ ~ N

(CH2fH) (CH2fH) (CH2fH)~
~0 ~ CN
~N X~

~8744~
w0951277s9 ~ t C ... ~ 01160 t (CH2CH, (CH2CH, (CH2CH, ~
~o ~N~ o~ o--10 t(CH2CH) (CH2fH) (CH2CH)~
N o COOH C=O
NH

CH2NH(CH3)2Cl~
t (CH2CI H) (CH2CI H) (CH2CH)~
20 ~O I-- N

CH2NH(CH3)2Cl ~ (CH2CH) (CH2CH) (CH2CH)~
30 ~O ~N~, CN
~!) CH2CH2C~2SO3 .

s ~ t ~
wo ssn77ss r~ , c ~ 2 ~ ~7448 . ~160 (CH2CH) (CH2CH) ~N~Oo COO
5 \ / H~ ,~"R
~N

~+(CH2CH) (CH2CH)~
~0 COO Mm (3 (~ = metal) ~(CH2CH)n (CH2CH)y~
COOR COONR
~(CH2CI H)x (CH2CH)y (CH2CH) ~0 ~ SO3H

21 87`448 W0 95/277S9 r~ 116~) t(CH2fH)~ (CH2fH)y (CH2CH)z~
COOR` COONR4 N
~N

t(CH2CI H)X (CH2 ICH)y (CH2 ICH)zt t (CH2CH2NH2~
COOR COONR4 COO~

~(CH2CH)X (CH2CH)y~ {(CH2CH2NH~)~
2 0 COOH COO~ -A second group of novel polymers (Group B) 30 again, contain first mer units having the structural formula (IVa) and/or (IVb) and second mer units containing pendant carboxyl, phosphate and/or sulfonate groups (P~ ied by structure tv) ) . The acidlc groups present in these latter mer units are preferably Wo 95/27759 2 1 8 7 4 4 ~ P~ 1160 neutralized as described above so as to provide the substituent R6; that is, neutralization is carried out using ammonia and/or an amine such as a lower alkyl amine (mono-, di- or trisubstituted), a diamine of the formula H2N-R8-NH2 where R8 is lower alkylene or arylene, a - ~ ic polyamine, a polymeric amine or imine (e.g., polyethylPnP;m;nP), a heterocyclic amine such as imidazole, or a combination of two or more of the foregoing. Examples of particularly suitable amines include imidazole, 4,4'-bipyridyl, tetramethyl-p-phenylPn~ m;nP, tetramethylethylPnerl;~m;n~ and triethylenetetraamine .
~or example, the polymers of Group B may be treated as described in the preceding section with respect to acidic binding materials in general , i . e., they may be neutralized initially with a volatile organic base such as ammonia so as to render ionic a fraction of the carboxylic acid, rhr~crhr~n;c acid and/or sulfonic acid groups, followed by further neutralization with a nonvolatile organic base, e.g., a lower alkyl substituted amine, a diamine, a mono-, di- or triethanolamine, a polymeric amine or imine, morpholine, N-methylmorpholine, or other heterocyclic amines such as imidazole. Again, between about 0 . 01% and 100% and preferably between about 10% to 100% of the pendant carboxylic acid, phosphonic acid and/or sulfonic acid groups may be neutralized in this manner, with the desired fraction of neutralized acidic groups, as noted above, dependent on the polymer and its 601ubility in water. With polymers that are more water soluble, fewer acidic groups need to be neutralized, while with polymers that are less soluble in water, more acidic groups will need to be neutralized.
In each ca6e, however, neutralization of Group B resins must be carried out to an extent suf f icient to render the polymer substantially water soluble.

2~ ~7448 WO 95127759 ~ . . r ~ 1/lX~ 0 With mer units having the structural formula (IVb), a similar neutralization technique may be used using a carboxylic acid (i.e., to increase the water sQlllhi l ity of the polymer), a dicarboxylic acid (for the 5 same reason, as well as to provide cros6-linking) such as adipic or succinic acids, or a polyacid. Examples of suitable acids include oxalic acid, fumaric acid, malonic acid, maleic acid, dillydL.,xyru",aric acid, succinic acid, glutamic acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,2-, 1,3- and 1~4-cyclt~hPYAnp dicarboxylic acid, 1,2- and 1,3-cyclopentane dicarboxylic acid, citric acid, tartaric acid, 1,2,3-, 1,2,4- and 1,3,5-benzene tricarboxylic acid, tricarballylic acid, 1, 2, 4, 5-benzene tetracarboxylic acid, norbornene 15 tetracarboxylic acid, 3, 3 ' 4, 4 ' -benzophenone tetracarboxylic acid, 1, 2, 3, 4, 5, 6-benzene hexacarboxylic acid, ~-amino acids such as aspartic acid, glutamic acid, and the like. Any one of these acids may also be substituted , e . g ., with one or more alkyl , typically 20 lower alkyl, groups, or they may be converted to anhydride f orm .
As with Group A resins, polymers of Group B may contain two or more different structural units of the first type and two or more different structural units of 25 the second type.
In the mer units of formula (IVa) and (IVb), R3, as noted above, is either 11YdLOg~II or lower alkyl, while R4~ and R4b preferably being lower alkyl. In the commercially available material 601d under the trademark 3 0 Carboset~, f or example, R3 and R4 are both methyl .
In the mer units of formula (V), RS is carboxylate, phosphate or sulfonate, although carboxylate is preferred. R6 is a cationic counterion associated with Rs, and is preferably a quaternary i ;llm moiety, 35 e.g., imidazolyl, pyrrolidinyl, NR74+, wherein R7 is Wogsl27759 ~ r; 2 ~ 8 7 4 4 8 ~ .'0l160 .
y-ll og~ll or lower alkyl, or R6 may represent a nitrogen atom in a polymer such as polyethylpnp;minpl or a nitrogen atom in a diamine cross-linking group, such that R6 provides for linkage to another segment of the resin 5 in an intramolecularly crosslinked network.
Still other polymers useful ~or formulating the present ink compositions are those of Groups C and D.
Group C polymers comprise first mer units having the structure (VI) -CHz-CH2-NH- and second mer units having 10 the structure (VII) -CH2-CH2-NR8- or (VIII) -CH2-CH(COOH)-, wherein, in structure (VII), RB
Le:p~ eSI~ S hydrogen, alkyl of 3 to 16 car~on atoms, or lower acyl - ~CO) -R9 where R9 is lower alkyl . Examples of such polymers are thus the following:
~(CH~-CH)~ tCH2CH2NH~
COOH

t(CH2CH2NH)~ ~CH2CH2 alkyl ~CH2CH2- N~ tCH2CH2NH~

WO95/277s9 ~ C -2~87448 r~"O~ . "~
Group D polymers have h~r~h~)nf~c containing a polyethylene glycol moiety and mer units having the E;tructures (IX), (X), ~XI) or combinations thereof.
1l O--C--NH
10 (IX) _ _ (X) --C--0~}

(XI) O
CH--(CH2)X--(NH)y--C--O
Rl -W09s/277s9 ~ 2 1 8 74 4 8 r~ oll60 In the5e ~LLUVI_UL~5~ R10 is -COOH or -NH2, x is O to 4, and y is 0 or 1. Particularly preferred polymers within this group are those derived from polyethylene glycols and an amino acid such as aspartic acid, glutamic acid, 5 lysine or 4-l~ydLv~y~Loline. Examples of such polymers are as follows:

O--IC--(CH2)X 1H--C--O--PEG--O
O O n 2 ~ INH2 ~ 0--ICI CH(CH2)2--ICI--0~
O
_ _ O O
Il 11 PEG--O--C--NH--CH--(CH2)~--NH--C--O
COOH

WO 95127759 ~ ; 2 ~ 8 74 4 8 P~ ll60 The polymers of Groups C and D, when containing ~cidic groups, are preferably neutralized as described previously, e.g., initially using a volatile neutralizing agent such as ammonia and subsequently with a nonvolatile 5 organic base such as imidazole or the like. As above, a particularly preferred omhorl; nt involves partial neutralization of the selected polymer's pendant acidic groups, followed by further neutralization with a heterocyclic amine such as imidazole, with the relative 10 amounts of polymer, ammonia and heterocyclic amine selected to provide the desired water solubility of the polymer.
For the present purpose, it should be emphasized that these novel polymers are particularly 15 useful in conjunction with the inventive ink formulations. }lowever, it will be appreciated that some or all of these polymers may have other utility as well, e. g ., in biomaterials or the like.
The novel polymers may be synthesized from 20 monomeric starting materials or they may be prepared by ~-h~mic;~lly modifying commercially available products, using techniques well known or readily available to those skilled in the art of polymer chemistry. Typically, to prepare Group A and Group B polymers, modif ication of 25 standard, commercially available polymers will take the form of treating the polymer so that it then contains both hydrophobic and ionic portions. Por example, commercially available resins which contain pendant carboxyl groups may be modified so that a fraction of 3 0 those groups are ionic and associated with hydrophobic counterions, e.g., imidazolium ions or quaternary ammonium salts. Examples of commercially available resins which may be modified in this way include the following acrylate-based polymers: Aqua-hydel (Lawter 35 Chemicals, Inc. ); Surcol'l9 (Allied Colloids Group WO 95/27759 ~ ~ r~ ; 2 1 8 7 4 4 8 P~ x,,' ~1160 Limited); Zinpol~D (Zinchem, Inc.); NeocrylD (Beatrice Foods Co. ); Carboset~ 514H (B.F. Goodrich); and JoncrylD
(S.C. Johnson ~ Son, Inc.). As noted above, generally between about o . 01% and 100% and preferably between about 10% to 10096 of the pendant carboxyl groups in such polymers may be rendered ionic in this manner.
Group C polymers containillg mer units (VI) and (VII) can generally be prepared by treating polyethylPnP;m;nP with any one of a variety of alkyl and/or aryl halides, typically C2-C16 alkyl and/or aryl halides, in a solvent such as methanol, dimethyl f nr~ - m i tl P, tetrahydrof uran, or the l ike . Po lymers containing mer units (VI) and (VIII~ can be prepared by copolymerization of aziridine and methyl acrylate under acidic conditions, f ollowed by A 1 kA 1 i ne hydrolysis of the acrylate group.
Group D polymers are generally prepared by f irst activating an ~-amino-protected diacid with N-hydroxy~ inimide to provide an activated ester, e.g., of aspartic acid, glutamic acid, or the like, and then reacting the activated ester with polyethylene glycol, and hydrolyzing the resulting product.
Methods of Manufacture and l~se:
~he aforementioned ink compositions may be prepared in any number o~ ways, as ~ill be appreciated by those working in the f ield of printing ink chemistry and ink manufacturing technology. A preferred method for formulating the ink compositions, however, involves first dispersing the selected colorant in deionized water (or obtaining a predispersed colorant/water admixture), followed by admixture with a solution of the selected binder material (s) in water, in turn followed by in~uL~uLation of additives 6uch as humectant, anti-foaming agent, and the like, and any species nprpcsAry Wo 9~/2MS9 ~ 8 7 4 4 8 . ~ I l ~a ~ r for purposes of neutralization, e.g., an amine such as ammonia and/or imidazole when an acidic resin is used.
This admixture is then stirred and mixed in either a f ine ball mill or an emulsifier mixer, and filtered-to achieve 5 a particle size of less than about 5 ~m, preferably less than about 1 ,um, in diameter.
The ink compositions of the invention may be used as jet printing inks, flexoyL~pllic inks, lithographic inks, 6creen printing inks, or the like.
10 Dpr~ ;n~ on the desired utility, the viscosity of the ink composition will need to be adjusted. For example, the preferred viscosity for a jet printing ink is in the range of approximately 1. 5 to 15 cP, more preferably in the range of approximately 1. 5 to 1o cP, and most 15 preferably in the range of approximately 3 to 5 cP, while the preferred viscosity for a screen printing ink is in the range of approximately loO to 400 cP, more preferably in the range of about 200 to 300 cP.
When tailored for use with pc printers, the 20 present ink composition need not be limited with respect to sonic velocity or resistivity. However, viscosity considerations are somewhat different than for other end uses, insofar as lower viscosities are generally preferred for pc printing, typically less than about 2.5 25 cP, preferably less than about 2. 0 cP, and most preferably in the range of about 1. 5 to 2 . 0 cP. It is generally desirable that when formulating the compositions for pc printers, the binder material should comprise a mixture of two monomeric materials, preferably 30 a di- or polyacid in combination with a di- or polyamine, as discussed hereinabove. Also, any components selected for use in pc printing ink compositions should be thermally stable, as they are subjected to higher temperatures, in general, than other types of inks.
35 Finally, pc printing inks may involve a different pH

,s- ;t ~
Woss/277sg ~ . P~l/~J,, '~0ll60 2 l 8744 8 range than other types of ink compositions, and should be chloride-free to avoid corrosion.
As explained in U.S. Patent No. 5,106,417 to Hauser et al., viscosity may be adjusted using any known 5 substances so long as those materials do not adversely affect the ink composition and the substrate on which the composition is ultimately applied. Suitable viscosity control agents include, for example, polyvinyl alcohol, hydroxylpropyl c~ lo~cel methyl cellulose, water soluble 10 acrylic resins and polyvinylpyrrolidone.
The ink compositions of the invention are not intended to be limited to use on particular substrates.
The present compositions are in fact quite versatile insofar as they may be used on paper, plastic, metal, 15 ceramics, and the like. In some cases, for example with a number of plastic materials, it may be n~ cc;~ry to pretreat the surface on which the ink is to be applied so that it is rendered hydrophilic, i.e., such that carboxyl or other ionized groups are provided thereon.

EYr~erimental The practice of the present invention will employ, unless otherwise indicated, conventional techniques of synthetic organic chemistry, 25 polymerization, ink manufacture, and the like, which are within the skill of the art. Such techniques are explained fully in the literature. See, e.g.: Kirk-Othmer, Encyclopedia of ~'h/~mlrsl7 ~erhnn70~7y (New York:
John-Wiley & Sons, latest edition); E~ouse, Modern 30 synthetic Reactions (Menlo Park, CA: The Benjamin/Cummings pllhlichin~ Company, 1972); and Odian, ~ Principles of Polymerization, Second Edition (New York:
John Wiley & Sons, 1981).
It is to be understood that while the invention 35 has been described in conjunction with the preferred wo g5~277sg ~ 1 8 7 4 4 8 . ~I/U~ _.'0~160 r, ~
specif ic Pmho~l i r 1_s thereof, that the description above as well as the examples which follow are intended to illustrate and not limit the scope of the invention.
Other aspects, advantages and modif ications within the 5 scope of the invention will be apparent to those skilled in the art to which the invention pertains.
In the following examples, efforts have been made to insure accuracy with respect to numbers u6ed (e.g., amounts, temperature, etc. ) but some experimental 10 error and deviation should be allowed for. ~nless indicated otherwise, t~ Lul ~ is in degrees Centigrade and y~ eS~UL 1: is at or near atmospheric .
Starting materials were obtained as follows:
maleic anhydride, from the Sigma Chemical Company (st.
15 Louis, MO); acetonitrile, acrylamide, 2-acrylamido-2-methyl-1-propane sulfonic acid, acrylic acid, acrylonitrile, acryloyl chloride, 1-dodecyl alcohol, imidazole, octadecylamine, polyethylPnP;m;nP, triacetin, vinylimidazole, N-vinylpyrrolidone and 20 vinyltrimethylsilane, from the Aldrich Chemical Company ~Milwaukee, WI); azobisisobutyronitrile, from Alfa (Ward Hill, MA); N-methyl-2-pyrrolidone, from GAF Corporation (New York, NY); Dispersol Black CR-N, Dispersol Black XF, from Zeneca, Inc. (Wilmington, DE); Acid Black 41, from 25 Crompton & Knowles (New York, NY); Hostafine Blàck TS, from ~oechst AktiengPcPl l Crh~ft (Frankfurt, Germany); and poly ;llm (acrylate co-acrylic acid) (CarbosetD
514H), from B . F. Goodrich (Akron, Ohio) .
r ~le 1 PolYmerization of N-VinYlPYrrolidone Vi"ylimidazole, ~n~ l eic Anhydride ( 1: 0 . 5: l l Maleic anhydride (3.2 g, 30 mmol) was dissolved in warm water (2.79 g). Then N-vinylpyrrolidone (3.33 g, 30 mmol) and vinylimidazole (1.54 g, 15 mmol) were added, . f,\ ~ ~ h ~ r.
~ WO 95/27759 ~ 'J 2 ~ 8 7 4 4 8 r~ 160 followed by azobisi60butyronitrile ~167 mg~ under an argon atmosphere. This mixture was heated to 65C and kept at that temperature for 48 h. The mixture was then cooled and water (6. 61 g) was added to bring the solution 5 to 50 wt. 96 terpolymer. As conf irmed using infrared (IR) and nuclear maynetic r~f~nn~n(-e (NMR) spectroscopy, the resin so provided had the structure ~(fH--CH2)X (IH--CH2)y (fH CIH)z~
~ ~IN COOH COOH

ExamPle 2 PolYmerization of N-VinYlpvrrolidone, A~rYlonitrile. and Maleic AnhYdride (1:0.5:1~
The ~L~cedu~ of Example ~ was repeated under identical conditions but with acrylonitrile (0.88 g, 15 mmol) instead of vinylimidazole. As before, a 50 wt.~6 terpolymer solution was prepared. As confirmed using IR
and NMR spectroscopy, the structure of the resin so provided was as follows:

.

W0 95/27759 i ' i` ~ 2 1 ~ 7 4 4 8 P~ 0 1160 .
(CH--CH2),~ (CH--CH2)y (CH CH) 5 ~0 CN COOH COOH
Examl~le 3 Polvmerization of N-VinYl~Vrrolidone.
Vinvlimidazole. and Acrvlonitrile rl~
N-vinylpyrrolidone (3.33 g, 30 mmol~, vinylimidazole (2.82 g, 30 mmol), and acrylonitrile (1.59 g, 30 mmol) were mixed together in acetonitrile (18. 06 g). Azobisisobutyronitrile (158 mg) was added and the mixture was flushed with argon, then heated at 6 o C f or 2 h. The temperature was raised to 80C and the mixture heated for 16 h. The terpolymer formed a precipitate 20 during the reaction. Acetonitrile was ~:v~ul~ted and the product was dis601ved in acidif ied water to obtain an 18 wt.% polymer solution. As confirmed using IR and NMR
spectroscopy, the structure of the resin so obtained was as follows:

t(CH2CH) (CH2CH) (CH2CH)~
3 ~ ~I CN

Wo 9s/27759 ~ 2 18 7 4 4 8 r~ . 1160 ~Y le 4 PQlymerization of N-VinYlDvrrolidone VinYlimidazole, An-l AcrvlamidomethvlDroDane Sulfonic Acid (1:1:0.4 N-vinylpyrrolidone t3.33 g, 30 mmol), vinylimidazole t2.82 g, 30 mmol), and 2-acrylamido-2-methyl-l-propane sulfonic acid t2.48 g, 12 mmol) were dissolved in water t2.88 g) under argon a~ -Are. Then A7nh;~ nhutyronitrile tl67 mg, 2 wt.% with respect to the ~ a) was added. This reaction mixture was heated to 60C for 2 h with constant stirring, then cooled. Water was then added to dilute the solution to 40 wt. 96 terpolymer. A h~ e.,us solution was obtained.
As confirmed using IR and NMR spectroscopy, the structure of the resin so obtained was as follows:

t(CH2CH) (CH~cH) (CHCH)~
~ ~I CONHC(Me)zCHzS03H
Exam~le 5 Polvmerization of N-Vinvlpvrrolidone Acrvlonitrile and 2 -Acrvlamido-2 -methvl - l-~roDane Sulf onic Acid ( 1: 1: 0 . 5 ) N-vinylpyrrolidone (3.33 g, 30 mmol), acrylonitrile (2 . 82 g, 30 mmol), and 2-acrylamido-2-methyl-l-propane sulfonic acid (3.1 g, 15 mmol) were dissolved in water under argon ~ re.
Azobisisobutyronitrile tl85 mg) was added and the reaction mixture heated to 75C for 18 h, after which it was cooled and more water was added to bring the solution to 30 wt.9~ terpolymer. As confirmed using IR and NMR

W095/277~9 ,~"~ f,, I ,~ 218744~ r~ sc ll60 spectroscopy, the structure of the resin so obtained was identical to that determined for the resin prepared in Example 4.
ExamPle 6 PolYmerization of N-VinvlPYrrolidone.
V;nYlimidazo-le~ and AcrYlamide (1:1:0.1 N-vinylpyrrolidone (3 . 33 g, 30 mmol~, vinylimidazole t2.82 g, 30 mmol), and acrylamide tO.214 g, 1 mmol) were dissolved in water tl2.72 g) under argon ~; ,h~re, Azobisisobutyronitrile tl27 mg) was added ~nd the reaction mixture heated to 80C for 15 h. The reaction mixture was allowed to cool, and then water was added to bring the solution to 14 . 5 wt. % pQlymer. As confirmed using IR and N~5R spectroscopy, the structure of the resin so obtained was as follows:
t(CH2CI H) (CH2CH) (CHiCH)t ~0 ~I CONHR

le 7 PolYmerization of N-VinYlPYrrolidone, VinYlimidazole, and VinYltrimethYlsilane rl:l:o.7) N-vinylpyrrolidone (3.33 g, 30 mmol~, vinylimidazole (2.82 g, 30 mmol), and vinyltrimethyl-silane (2 . 22 g, 21. 9 mmol~ were dissolved in acetonitrile (2.79 g) under argon ,i ,hore. Then azobisisobutyro-nitrile (167 mg) was added and the mixture heated to 75C
for 18 h. Acetonitrile was evaporated to yield the W095/277~9 ` `~ '` 21 ~7448 I l~u~ c~l60 terpolymer, and this polymer wad dis601ved in absolute ethanol to obtain a 50 wt. % polymer solution. As conf irmed using IR and N~R ,,,ue~ LL u _cu~y, the structure of the resin so obtained was as follo~s:

t(CH2CI H) (CH2CH) (CH~CH)t 0 ~ ~1 SiMe3 r le 8 Polvmerization of N-VinvlPvrrolidone~
Acrvlonitrile. and Vinvltrimethvlsilane (1:1:1 N-vinylpyrrolidone (6 . 66 g, 60 mmol), acrylonitrile (3.18 g, 60 mmol), alld vinyltrimethylsilane (8.9 g, 60 mmol) were dissolved in acetonitrile (6.25 g) under an inert a; ~ re. Azobisisobutyro-nitrile (374 20 mg) was added and the mixture heated to 70C for 2 h.
The terpolymer precipitated in acetonitrile. The precipitated polymer was dissolved in a mixture containing equal amounts of DMF and acetonitrile to obtain a 33 wt.% polymer solution. As confirmed using IR
25 and NMR ~ye-;L~oscopy, the ~LLU~:LUr~: of the resin so obtained was as follows:
--(CH-CH2) (CH-CH2) (CH--CH2)--~0 CN SiMe3 ~t 87448 WO95/27759 ~ t ~ , r~ ,'0~l60 r A 11'1 n 1 e 9 rAolymerization of N-VinYl,,Yrrolidone, VinY];mi(~A7ole~ ~n~l VinYltrimethYlsilane (1:1:1) N-vinylpyrrolidone (6. 66 g, 6D mmol), 5 vinylimidazole, (5. 64 g, 60 mmol), and vinyltrimethylsilane (8.9 g, 60 mmol) were dissolved in ~cetonitrile (7 . 06 g) under argon a; ~ ^re.
Azobisisobutyronitrile (424 mg) was added and the mixture was heated to 70C for 18 h. This mixture was cooled and 10 then acetonitrile (15.1 g) was added to bring the solution to 50 wt.%. A6 confirmed using IR and NNR
6pe~ L OB~ )y, the structure of the resin so obtained was as f ollows:

t(ClH_cH2)x (CIH-CH2)y--(CIH-CH2)z~
2 0 ~ ~ ~ SiGH3 r le 10 PolYmerization o~ N-VinYlr~yrrolidone~
Vinvlimidazole, and AcrYlic Acid 13:0.5:1~
N-vinylpyrrolidone (4 .168 g, 37 . 5 mmol), vinylimidazole, (0.588 g, 6.25 mmol), and acrylic acid (0.9 g, 12.5 mmol) were dissolved in water (8.48 g) under an argon atmosphere . Azobisisobutyronitrile ( 113 mg) was added to the above reaction mixture and the mixture heated to 75C for 1.5 h. The polymer gelled. Enough water was added to the gelled polymer to bring the Wo g5/277ss , ~ 2 ~ 8 7 4 4 8 ~ / 1160 solution to 14 wt. ~6, and the preparation was stirred at room t~ ~LULt: overnight to get a homogeneous solution.
As confirmed by IR and NMR speuLlu6~uyy, the ~LLu~;LuL` of the resin so obtained was as follows:

~(CH2CH) (CH2CI H) (CH2CH)~
0 ~ ~1 COOH
Exammle ll PolYmerization of N-VinvlPyrrolidone VinYlimidazole.
;, ntl MethYl MethacrYlate (l:l:0.75~
N-vinylpyrrolidone (6 . 66 g, 60 mmol), vinylimidazole, (5 . 64 g, 60 mmol), methyl methacrylate (3.88 g, 4.5 mmol) and azobisisobutyronitrile (0.32 mg) were dissolved in water (10.78 g) under an argon 20 c,i -_ '^re. This mixture was heated to 55OC and kept at this temperature for 3 min. The solution became highly viscous. Immediate cooling of the mixture resulted in a soft solid. Water was added to this solid to bring the solution to 15 wt. % polymer. The polymer did not 25 dissolve completely on standing at room temperature overnight, therefore, the solution was treated with 8 N
HCl (bringing it to a 14 . l wt. % solution) and heated at 80C for 8 h; a homogeneous solution resulted. As confirmed using IR and NMR spectroscopy, the structure of 30 the resin so obtained was as follow~:

Wo 95/277~9 ~ C~ I ~ 2 ~ 8 7 4 4 8 P~./,j~ ''0~160 CH
t(CH2CH) (CH2CH)--(CH2C )~

Ell le 12 Polvmerization of N-VinYl~vrrolidone, Vi~Yl;n~idazole. and CH3(CH2L17NHCOCH=CH2 (1:1:0.05) (a.) Preparation of CH3(CH2)17NHCOCH=CH2:
octadecylamine (CH3(CH2)17NH, 14.5 g) (90%
15 terhn;c~l grade) was dissolved in chloroform (200 mL), and freshly distilled triethylamine ( 15 mL) was added. A
clear solution formed. This solution was cooled with ice, acryloyl chloride (8 mL) was added, and the solution was stirred at room temperature for 18 h. Water (200 mL) 20 was added, followed by just enough dilute HCl to neutralize excess triethylamine. Then the chloroform layer was washed with water and dried over anhydrous MgS04 . Chlorof orm was evaporated to o~tain the LuLL~y~JIlding amide, CH3(CH2)17NHCOCH=CH2, in 75% yield.
(b. ) N-vinylpyrrolidone (3.33 g, 30 mmol), vinylimidazole (2.82 g, 30 mmol), the acrylamido derivative obtained in part (a.) (0.48 g, 1.5 mmol), and azobisisobutyronitrile (132 mg) were mixed in acetonitrile (13.26 g). This mixture was heated to 85C
for 2.3 h. A homogenous viscous solution was obtained.
Acetonitrile was evaporated to qet a solid polymer. This polymer was dissolved in acidif ied water to bring the polymer solution to 12 wt . % . As conf irmed using IR and NNR ~,~eLLL~SCopy, the structure of the polymer was as follows:

W095/27759 ~" '~,r, p t ~ 2 1 8 7448 r~
~(CH-CH2),~-- ~cH-cH2)y--(CH-CH2)z~
~ N~ ~(CH2)l7CH3 Exammle 13 Treatment of N-Vinyl~yrrolidone/
AcrYlic Acid Co~olYmer with Imidazole The copolymer N-vinylpyrrolidone/acrylic acid (molar ratio of those repeat units=3:1, mol. wt=80,000) (5 g) was mixed with imidazole (0.21 g) in water (20.84 g) solution. This mixture was 6tirred very well to obtain a homogenous solution. In this experiment, 25%
acrylic acid was neutralized. The structure of the 20 product was confirmed using IR and NMR spectroscopy to be the following:
t(CH2CH)--(cH2cH)~
~ ~ COO
N
6~
N

W095/27759 , i~ f !~ 218744~ c~l60 ~
ExamPle 14 A black jet printing ink was prepared as follows. Dispersol Black CR-N ~4 . 9 g) and Dispersol Black XF t3.0 g), were dispersed in APir~ni7Pd water. A
5 10-20 wt. % solution of poly ammonium (acrylate-co-acrylic acid) tCarboset~D 514H) was then prepared in deionized water as well (a total of 100 g water was used), and mixed at room t~ clLULe using a conventional mixer.
The pigment dispersion was then admixed with the resin 10 solution, and the following additional components were incorporated into the admixture: 12.5 g 1-dodecyl ~lcohol, as a de-foaming agent; o.1 g ;1n;AA701P
(Aldrich), to functionalize the resin, i.e., to convert it to polyimidazolium (acrylate-co-acrylic acid); and 0. 2 15 g N-methyl-2-pyrrolidone and 0 . 2 g triacetin, as humectants . The admixture was then mixed in a f ine ball mill and filtered through a 22 ~m filter, a 5 ,um filter and a 1. 2 ~Lm f ilter in succession . The ink was then used to write on white paper, allowed to dry for five minutes, 20 ~nd tested for fastness by dipping the paper for several hours in different liquids. The dried ink was found to be insoluble in all of the liquids tested, ;nrlllA;n~
water, toluene and isopropyl alcohol.
~l~ATnnle lS
A black j et printing ink was prepared as follows. Dispersol Black CR-N (49 g) and Dispersol Black XF (30 g) were dispersed in deionized water. A 40% wt. %
solution of poly ;ll~n (acrylate-co-acrylic acid) (CarbosetlD 514H) was prepared in deionized water as well (a total of loO g water was used), and mixed at room temperature using a conventional mixer. The pigment dispersion was then admixed with the resin solution, and the following additional components were incorporated into the admixture: 12.5 g 1-dodecyl alcohol, as a de-W095/277s9 ~ t-~ 2187448 r~ J 1160 foaming agent; 1. 0 g imidazole, to functionalize the resin; and 2. 0 g N-methyl-2-pyrrolidone and 2 . 0 g triacetin, as humectants. The admixture was then mixed in a fine ball mill and filtered through a 22 ~m filter, 5 a 5 l~m filter and a 1. 2 ~m filter in succession. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding example. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene and 10 isopropyl alcohol.
Exam~le 16 An ink composition according to the invention was prepared by i~lmi~ing 2.5 g poly -nillm (acrylate-co-acrylic acid) (Carboset~D 514H) with 7 . 5 g deionized water, and adjusting the pH of the admixture to 8.5 using ;~lm hydroxide. 1.6 g of 50% polyethylPnP;m;nP
predissolved in 8 . 4 g deionized water, adjusted to pH 10 with ;llm hydroxide, was added to the resin/water solution. Five drops of Hostafine Black TS (Hoechst CPlAnpce) dye was then added and the mixture stirred.
The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene, acetone, isopropyl alcohol, and detergent solution (pH 8 ) .
Exam~le 17 3 0 l~n ink composition according to the invention was prepared by :4~1mi~;ng 2.5 g poly ammonium (acrylate-co-acrylic acid) (Carboset~lD 514H) with 7 . 5 g deionized water, and adjusting the pH of the admixture to 8.5 using ammonium hydroxide. 1.6 g of 50% polyethylPnP;m;nP
predissolved in 8.4 g deionized water, adjusted to pH 10 WO 95127~59 ~ 2 1 B 7 4 4 8 ~ '0~160 with ~nillm hydroxide, was added to the resin/water solution. O. 6 g Acid Black 41 dye was then added and the mixture stirred. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for 5 f2stness as in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, ~nrll-~l;nj water, toluene, acetone, isopropyl alcohol, and detergent solution (pH 8).
~y~mnle 18 An ink composition according to the invention was prepared by ~miYinj 1.25 g polyacrylic acid with 8.75 g deionized water, and adjusting the pH of the admixture to lO using a-mmonium hydroxide. O . 32 g of 15 polyethylPnP;minP predissolved in 12 g deionized water was added to the resin/water solution. Seven drops Hostaf ine Black TS dye was then added and the mixture stirred. The ink was then used to write on white paper, ~llowed to dry for five minutes, and tested for fastne6s 20 as in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene, acetone, isopropyl alcohol, and detergent solution (pH 8).
r le l9 An ink composition according to the invention was prepared by dispersing pigment (Hostaf ine Black TS) in ~Qi~An~7Qfl water to give a 5.6 wt.96 solution. A 31.9 wt. % solution of poly ammonium (acrylate-co-acrylic acid) (Carboset~ 514H) was prepared in deionized water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional r AntS were in~VL~UL~ed into the admixture: O. 08 wt. % imidazole;
0.31 wt.96 N-methyl-2-pyrrolidone; and O.19 wt.~c -Wogs/27759 ~ 2 ~ 8 7448 r~ c triacetin. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastne66 as in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, ;n~ ;n~ water, toluene, acetone, isopropyl alcohol, and detergent solution ~pH 8 ) .
Exam~le 2 0 An ink composition according to the invention was prepared by dispersing pigment (Hostafine Black TS) in deionized water to give a 4 . 8 wt. % solution . A 52 . 5 wt. 96 solution of poly ammonium (acrylate-co-acrylic acid) (Carboset~ 514H) was prepared in ~Pl nni zed water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then adnixed with the resin solution, and the following additional _ ~ ts were incu~u~ted into the admixture: 0.07 wt.~6 imidazole;
O .16 wt. % N-methyl-2-pyrrolidone; and 0 .15 wt. ~6 triacetin. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding examp] es. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene, acetone, isopropyl alcohol, and detergent solution (pH 8).
r le 21 An ink composition according to the invention was prepared by dispersing pigment (Hoechst Hostafine Black TS) in deionized water to give a 4 .1 wt. % solution.
A 49.9 wt.96 solution of poly ;llm (acrylate-co-acrylic acid) (Carboset$ 514H, obtained from B.F.
- Goodrich) was prepared in deionized water, and mixed at room temperature using a convention,al mixer. The pigment dispersion was then admixed with the resin solution, and 0 . 06 wt. ~6 imidazole was then incorporated into the WO95/27759 ~ S 21 87448 ~ c 1160 ~dmixture. The ink was then used to write on white paper, allowed to dry for fivQminutes, and tested for fastness as in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, 5 includiny water, toluene and isopropyl alcohol.
r le 22 An ink composition according to the invention was prepared by di6persing pigment (Hostafine Black TS) in ~ n~zed water to give a 5.5 wt.% solution. A 50.0 wt. % solution of poly ammonium (acrylate-co-acrylic acid) (Carbosetl 514H) was prepared in deionized water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional components were incorporated into the admixture: 0.07 wt.% imidazole;
0.22 wt.% N-methyl-2-pyrrolidone; and 0.19 wt.%
triacetin. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene and isopropyl alcohol.
R~rA ~n 1 e 2 3 An ink composition according to the invention was prepared by dispersing pigment tHostafine Black TS) in deionized water to give a 5 . 5 wt. % solution. A 49 . 6 wt. % solution of poly ammonium (acrylate-co-acrylic acid) (CarbosetC9 514H) was prepared in deionized water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional components were incuL~uLated into the admixture: 0.07 wt.% imidazole;
0.22 wt.% N-methyl-2-pyrrolidone; and 0.20 wt.%
35 triacetin. The ink was then used to write on white W09sl277s9 ~ f~ 2~87448 ~ '0~160 paper, allowed to dry for five minutes, and tested for fastne66 a6 in the preceding examples. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene and isopropyl alcohol.
Exam~le 24 An ink compo6ition according to the invention wa6 prepared by di6persing pigment (Hostaf ine Black TS) in deionized water to give a 5.5 wt.% solution. A 31.8 10 wt. % solution of poly ammonium (acrylate-co-acrylic acid) (CarbosetD 514H) was prepared in deionized water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional components were 15 in-UL~oLC:ted into the admixture: 0.07 wt.~ imidazole; and 12 . 8 wt. % ammonium hydroxide. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding examples.
The dried ink was found to be insoluble in all of the 20 liquids tested, including water, toluene and isopropyl alcohol .
ExamPle 25 An ink composition according to the invention 25 was prepared by dispersing pigment (Hostafine Black TS) in deionized water to give a 5 . 5 wt. % solution. A 32 . 6 wt.% solution of poly ;llm (acrylate-co-acrylic acid) (Carbosetl 514H) was prepared in deionized water, and mixed at room temperature using a conventional mixer.
30 The pigment dispersion was then admixed with the resin solution, and the following additional ~nts were incorporated into the admixture: 0.07 wt.% imidazole; and 6 .1 wt. % ammonium hydroxide. The ink was then used to write on white paper, allowed to dry for five minutes, 35 and tested for fastness as in the preceding examples.

W09~/27759 ~ 21 8744~ C~0~l60 The dried ink wa6 found to be insoluble in all of the liquids tested, including water, toluene and isopropyl alcohol .
~YAmnle 26 An ink composition according to the invention wa6 prepared by dispersing pigment (Hostafine Black TS) in deionized water to give a 5 . 5 wt. % solution. A 33 . 0 wt.% solution of poly ammonium (acrylate-co-acrylic acid) (Carboset$ 5141~) was prepared in deionized water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional ~~ ~nPnts were incorporated into the admixture: 0.07 wt.% ;m;~R~olpi and

4. 6 wt. % ammonium hydroxide. The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding examples.
The dried ink was found to be insoluble in all of the liquids tested, including water, toluene and isopropyl alcohol.
r le 27 An ink composition according to the invention was prepared by dispersing pigment (~lostafine Black TS) in deionized water to give a 5 . 5 wt . % solution. A 45 . 2 wt.% solution of poly ammonium (acrylate-co-acrylic acid) (Carboset$ 514H) was yrc:y~ d in deionized water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional I ~nts were incorporated into the admixture: 0 . 07 wt. % imidazole; and 1.0 wt.% anti-foaming agent (Wacker S670). The ink was then u6ed to write on white paper, allowed to dry for f ive minutes, and tested f or f astne66 as in the preceding ,- l Pc . The dried ink was found to be insoluble in all ' i' ~` ~ f) t~
W0 9S/27759 2 1 8 7 4 4 ~3 F~ 60 of the liquids tested, including water, toluene and isopropyl alcohol.
Exam~le 28 An ink composition according to the invention was prepared by dispersing pigment (Hostaf ine Black TS) in deioni2ed water to give a 5 . 5 wt. 96 solution. A 32 . 3 wt. ~6 solution of poly ammonium (acrylate-co-acrylic acid~
(Carboset~ 514H) was prepared in clp;nn;7pcl water, and mixed at room temperature using a conventional mixer.
The pigment dispersion was then admixed with the resin solution, and the following additional _ 7nPntS were incorporated into the admixture: 0 . 07 wt. % imidazole;
O . 23 wt. 96 N-methyl-2-pyrrolidone; a . 19 wt. % triacetin;
and 1.0 wt.% anti-foaming agent (Wacker S670). The ink was then used to write on white paper, allowed to dry for five minutes, and tested for fastness as in the preceding example6. The dried ink was found to be insoluble in all of the liquids tested, including water, toluene and isopropyl alcohol.
r le 29 An ink composition according to the invention may be prepared by dispersing a pigment such as Hostafine Black TS in deionized water to give a 0.1 wt.96 to 20 wt.%
solution, optimally about a 5 wt. % solution. A solution of the polymer synthP~; 7Pd in Example 1 is prepared in dP;nn;70d water, and mixed at room temperature using a conventional mixer. As in the preceding examples, the pigment dispersion is then admixed with the resin solution, and the following additional r, --ntS may be incorporated into the admixture: ammonia, imidazole, ~nd/or polyethylPnPiminP, or the like, to functinn~l i 7e - the polymer; N-methyl-2-pyrrolidone and triacetin, as humectants; anti-foaming agents such as Siliconantifoamer . 2 1 ~7448 WO9!;/27759 ~ }!' '" r~l~u~ o~l60 5670 (Wacker) or Carboflow 32W (B.F. Goodrich); and yl~s~Lv~tivesl biQÇiclo~, and the like. The ink may then used to write on paper, allowed to dry for five minutes, and tested for fastness in various liquids. The dried ink is expected to be insoluble in water as well as in solvents such as toluene and acetone.
r le 30 An ink composition according to the invention may be pl~:p~ d by dispersing a pigment such as ~ostafine Black TS in deionized water to give a 0 .1 wt. % to 20 wt. %
solution, optimally about a 5 wt. % solution. A solution of the polymer synthesized in Example 4 is prepared in deionized water, and mixed at room temperature using a conventional mixer. As in the preceding examples, the pigment dispersion is then admixed with the resin solution, and the foll4wing additional components may be in~;oL~IL~ted into the admixture: ammonia, imidazole, and/or polyethylpnp;m;n~ or the like, to functionalize the polymer; N-methyl-2-pyrrolidone and triacetin, as humectants; anti-foaming agents such a6 S;l;rnnlntifoamer S670 (Wacker) or Carboflow 32W (B. F. Goodrich); and preservatives, biocides, and the like. The ink may then used to write on paper, allowed to dry for five minutes, and tested for fastness in various liquids. The dried ink is expected to be insoluble in water as well as in solvents such as toluene and acetone.
r le 31 An ink composition according to the invention may be prepared by dispersing a pigment such as ~ostaf ine Black TS in deionized water to give a 0 .1 wt . % to 2 0 wt . %
olution, optimally about a 5 wt. % solution. A solution of the polymer synthesized in Example 6 is prepared in IPinn;~ water, and mixed at room temperature using a Wogs/277s9 ~;fi~ 2187448 r~ 6o conventional mixer. As in the preceding examples, the pigment dispersion is then admixed with the resin solution, and the following additional c -- Ls may be incuL~uuLa~ed into the admixture: N-methyl-2-pyrrolidone

5 and triacetin, as humectants; anti-foaming agents such as SilicnnAntifoamer S670 (Wacker) or Carboflow 32W (B.F.
Goodrich); and yL ~sel vtltives , biocides , and the like .
The ink may then used to write on paper, allowed to dry for five minutes, and tested ~or fastness in variou6 10 liquids. The dried ink is expected to be insoluble in water as well as in solvents such as toluene and acetone.
Exam,,le 32 An ink composition according to the invention 15 may be prepared by dispersing a pigment such as Hosta~ine Black TS in deionized water to give a 0 .1 wt. % to 20 wt. %
solution, optimally about a 5 wt. 96 solution. A solution of the polymer synthesized in Example 10 is prepared in deionized water, and mixed at room temperature using a 20 conventional mixer. As in the preceding examples, the pigment dispersion is then admixed with the resin solution, and the f ollowing additional _ ^ntS may be incorporated into the admixture: ammonia, imidazole, and/or polyethylPn~im;n~ or the like, to functionalize 25 the polymer; N-methyl-2-pyrrolidone and triacetin, as humectants; anti-foaming agents such as Si 1 i ~AnnAntifoamcr S670 (Wacker) or Carboflow 32W (B.F. Goodrich); and preservatives, biocides, and the like. The ink may then used to write on paper, allowed to dry for ~ive minutes, 30 and tested for fastness in various liquids. The dried ink is expected to be in501uble in water as well as in solvents such as toluene and acetone.

Wo 95127759 ~ 2 1 f~ 7 4 4 8 r~.,- o 1160 .
~Ar~ e 33 An ink composition according to the invention may be prepared by di6persing a pigment such as Hostaf ine Black TS in deionized water to give a 0.1 wt. 96 to 20 wt. %
5 solution, optimally about a 5 wt. % solution. A solution of the polymer synthesized in Example 13 is prepared in deionized water, and mixed at room temperature using a conventional mixer. As in the preceding exsmples, the pigment dispersion is then admixed with the resin 10 solution, and the following additional r~-rrn~nts may be incorporated into the admixture: N-methyl-2-pyrrolidone nnd triacetin, as ~ - ~ntS; anti-foaming agents such as ~il;ron~ntifoamer 5670 (Wacker) or Carboflow 32W (B.F.
Goodrich); and preservatives, biocides, and the like.
15 The ink may then used to write on paper, allowed to dry ror five minutes, and tested for fastness in various liquids. The dried ink is expected to be insoluble in water as well as in solvents such as toluene and acetone.
Exam~le 34 The terpolymer of Example 1, prepared from N-vinyl pyrrol i~l;n~ , acrylonitrile and maleic anhydride, was synth~ci ~ed and used to formulate an ink composition.
The polymer was f ound to be insoluble in water but soluble in ;ArAl water having a pH of approximately 9 . 0 to 9 . 5 . Accordingly, an ink was prepared in an l vehicle, having the following composition:
Terpolymer (50% aqueous suspension), 2 . 0 g;
Deionized water, a. o g;
NH40H, sufficient to give a pH of s.o; and }lostaf ine Black TS, O .1 g .

W0 95l27759 ~ 1h~ ; 2 t ~ 7 4 4 8 r~l, l,~ c o 1160 This ink composition was applied to a substrate and allowed to dry. The dried ink was found to be water-fast .
r le 35 The terpolymer of Example 3, prepared from N-vinyl pyrrol i~linonP, vinyl imidazole and acrylonitrile, was synthesized and used to formulate an ink composition.
The polymer was found to be water soluble. Accordingly, an ink formulation was prepared in water, having the following composition:
Terpolymer (20% aqueous 601ution), 5. 0 g;
Deionized water, 5 . O g; and Hostafine Black TS, 0. 06 g.
As with the ink formulation of Example 34, this composition was found to be water-fast.
r le 36 The polymer of Example 8, prepared from N-vinyl pyrrol ;riinonP, acrylonitrile and vinyl trimethyl silane, was synthesized and used to prepare an ink formulation.
The polymer was found to be soluble in a 3 :10 mixture of acetonitrile and water. Accordingly, an ink formulation was prepared containing acetonitrile, and, like the previous formulations, found to be water-fast.
Polymer, 1. 0 g;
Deionized water, 10 . 0 g;
Acetonitrile, 3 . 0 mL; and Hostafine Black TS, 0.06 g.

WO 95/27759 ~ f~ 2 1 8 7 4 4 8 r~ 4160 F le 37 The terpolymer of Example 6, ~L~ Led from N-vinyl pyrrol i~l;nc-nP, vinyl imidazole and acrylamide, was synthesized and used to formulate an ink composition.
The polymer was found to be water soluble. An ink formulation was prepared in water, having the composition set forth below, and found to be water-fast.
Terpolymer (33% aqueous solution), 3 . 0 g;
Deionized water, 7 . 0 g;
Hostafine Black TS, 0.07 g; and Polyacrylic acid (10% aqueous solution), 1.5 g.
FY;~ le 38 A dye-based ink composition according to the invention was prepared as f ollows . Ten grams Carboset5 1594, 4 g of Duasyn Direct black dye (Hoechst ~PlRnP~e) and 40 mL of ~P;on; ~Pd water were placed in a beaker and stirred at room temperature for 10 minutes. In a separate beaker, polyethylPne;m;nP, M", 500,000 (4.5 g) was dissolved in 20 mL of water by stirring for 10 minutes. The polyethylPnPim;nP solution was then added to the Carboset5 solution and the stirring continued.
Another 2 0 mL of water was added with washings of the polyethylPnp;m;ne-containing beaker. The stirring was continued at room temperature. N-methyl pyrrolidone (5%) and silicon surfactant I,-603 (0.5~6) were also added to yield the ink formulation.
In other ink f ormulations prepared with these ^ntS, only 75% each of Carboset5 and polyethylPnp;m;np~ 5096 each of Carboset~ and polyethylPnpim; ne and 25% each of Carboset~ and polyethylPnP;m;nP were used. In still other formulations, polyethylPnP;m;nPc of varying molecular wo 951277~9 ~ ~ 2 1 8 7 4 4 8 . ~ 1160 r ~;
weight~ , 700, 2,000, 50,000 and 60,000--were used to prepare ink compositions.
These formulations showed very good water fastness and no bleeding after drying on plain paper.

r- le 39 A dye-ba6ed ink composition according to the invention was prepared as follows. Five grams Carboset0 1594, 4 g of Duasyn Direct black dye (Hoechst Celanese) and 40 mL of deionized water were placed in a beaker and stirred. Triethanolamine (5 g) was dissolved separately in 2 0 mL of water . The two solutions were mixed and another 20 mL of water was added. The mixture was stirred at room temperature. N-methyl pyrrolidone (5%) and silicon surfactant L-603 (0.5%) were also added. The formulation showed very good water ~astness after spotting on plain paper.
r le 40 A dye-based ink composLtion according to the invention was prepared as f ollows . Ten grams Carboset5 1594, 4 g of Duasyn Direct black dye (Hoechst CPlAn~se) and 40 mL of deionized water were placed in a beaker and stirred. Triethylenetetramine (3 g) was dissolved in water (20 mL) separately by stirring and mixed with the Carboset~ and dye solution . Another 2 0 mI, of water was added and the contents stirred at room temperature. N-methylpyrrolidone (5%) was also added. This formulation displayed good water fastness by spotting on plain paper.

r le 41 A dye-based ink composition according to the invention was prepared as follows. A mixture of polyethylPnP;m;nP, Mw 750,000 (2.5g) and 1,2,4-benzenetricarboxylic acid (5 g) were mixed with 40 mL of W095/27759 , ~ ~ ~~ r~ r~ 160 water and stirred at room temperature. The two did not dissolve in water and formed an opaque dispersion. The dispersion was treated with ammonia and became a clear solution after stirring for 10-15 minutes. Duasyn Direct black dye (Hoechst GP1 ;~nPCP, 4 g) and N-methylpyrrolidone (5 mL) were added along with deionized water until the total volume was approximately 80 mL. The contents were then stirred at room temperature. This formulation displayed very good water fastness by spotting on plain paper.
Analogous f ormulations were prepared using polyethylPnPiminPc of varying molecular weights, i.e., M,, 700, 2,000, 5,000 and 25,000, and by replacing ammonia with methylamine, dimethylamine, ethanolamine, diethanolamine and morpholine. All of these formulations displayed good water fastness after drying on plain paper .
r le 42 A dye-based ink composition according to the invention was prepared as follows. A mixture o~ 1,2,4-benzenetricarboxylic acid (8 g) and 60 mL of 10~6 solution of triethylenetetramine were stirred together f or 2 hours. Duasyn Direct black dye (Hoechst Celanese, 2.8 g) was then added to the solution and stirring was continued until all components dissolved. Triethanolamine (lo mL) and N-methylpyrrolidone (10 mL) were also added. The resultant composition showed very good water fastness and no bleeding by spotting on plain paper.
Analogous formulations were prepared by replacing triethanolamine with ethanolamine, diethanolamine and morpholine. These also were found to have very good water fastness after drying on plalin paper, and did not display any bleeding.

WO 95/27759 ~ ~ 2 ~ 8 7 4 4 8 ~ 160 ~yAmrlle 43 A dye-based ink composition according to the invention was prepared as follows. Polyethylon~;min~/ M"
750~ ooo (4 g) was dissolved in 40 InL of deionized water and 4 g Duasyn Direct Black dye added after the polyethyl~rl~imin~ had dissolved. The mixture was stirred at room temperature. 3, 3 ', 4, 4 ~-BenzophPnn~
tetracarboxylic dianhydride was mixed with 20 mL of water in a beaker and ammonia was added until the anhydride dissolved completely. The two solutions were mixed and another 20 mL of water was added, followed by further stirring at room temperature. N-methyl pyrrolidone (5-10%) and ethylene glycol (29c) were also added. After spotting on plain paper, the ink formulation displayed very good water fastness.
Analogous formulations were pLt:~aLe:-l using polyethyl~n~im;n~ of varying molecular weight, e.g., ~w 700, 2000, 5000 and 25,000, and by replacing ammonia with methylamine, dimethylamine, ethanolamine, diethanolamine, triethanolamine and morpholine. Ink formulations were obtained having equivalent water fastness to that described above.
F~/ le 44 A dye-based ink composition according to the invention was prepared as follows. Carboset~l9 1594 (5 g) was dissolved in 40 mL of water by stirring at room temperature. Duasyn Direct black dye tHoechst C~lAnc~e, 4 g) was added and stirring was continued until the dye dissolved. Poly(vinylpyridine) (1.5 g) was dissolved separately in 20 mL of water and this solution was added to the Carboset D and dye mixture and stirred at room temperature. N-methylpyrrolidone (5%) and glycerol (29~) were also added. After spotting on paper, the composition showed good water fastness and no bleeding.

W095/27759 i r~ ~ r 2 1 ~74 48 1 ~ J. C0~I60 F1~'Amn1e 45 A dye-ba6ed ink composition according to the invention was prepared as follows. Triethylenetetramine (4 g) was di6601ved in 40 mL of water and Duasyn Direct 5 black dye (Hoechst relAnf~ce, 4 g) was added. The contents were stirred until the dye dissolved. Cltric acid (4 g) was dissolved separately in 20 mL of water with 6tirring and added to the triethylene tetramine solution. A solid 6eparated out which di6601ved upon stirring. To thi6 601ution N-methyl pyrrolidone (5-10%) and triethanolamine (5-10%) were added and the 6tirring continued. The composition 6howed very good water fastness a~ter spotting on paper. The ink was filtered through 5 ~ 0 and 1. 2 ~m f ilteEs and printed on plain paper u6ing a Hewlett-Packard 550C De6k Jet printer.
Analogou6 formulations were prepared by replacing triethanolamine with ethanolamine, diethanolamine, (+)-l-amino-2,3-propanediol and morpholine. The6e ink formulations were al60 found to 20 have excellent water fastness and did not bleed after spotting on plain paper.
F~A mnle 4 6 A dye-based ink compo6ition according to the invention was ~epllIed a6 follow6. Tartaric acid (4 g) 25 was dissolved in 20 mL of deionized water. In a separate beaker, triethylenetetramine (4 g) was dissolved in 40 mL
of ~F'i nni 7er~ water with 6tirring. To thi6 was added 4 g of Duasyn Direct ~lack dye (Hoechst ~1 An~ce) and the stirring continued until the dye had dissolved. The 30 tartaric acid solution wa6 then added and 6tirring wa6 continued. N-methylpyrrolidone (5~6) and triethanolamine (5%) were al60 added. A6 with the preceding formulation, thi6 ink wa6 te6ted by 6potting on paper and then printing using an Hewlett-Packard 550C De6k Jet printer.

8 1 .~
W09~/2~7s9 ; 2 1 ~ 7448 1~I/U~ '0~160 Analogous formulations were prepared by replacing triethanolamine by ethanolamine, diethanolamine, morpholine and (+) -1-amino-2, 3-propanediol. Inks so prepared displayed very good water fastness and did not bleed after application to plain paper .
; le 47 A dye-based ink composition according to the invention was prepared as follows. Four g of 3,3',4,4'-hPn7orhPnnnP tetracarboxylic dianhydride were placed in 3 o mL of water and stirred, f ollowed by dropwise addition of aqueous ammonia until the anhydride dissolved completely. Duasyn Direct black dye (Hoechst Celane6e, 5 g) was added, and the solution was stirred.
Triethyl Pnt~te~ramine (2 g) was dissolved separately in 1o mL of water. The two solutions were mixed. N-methylpyrrol ~t~nnnp (8 mL) and triethanolamine (8 mL) were added and the contents stirred at room temperature.
The total volume of the solution was made up to loO mL by further addition of water. This was ~iltered through 5 and 1.2 ,~m millirore filters. This composition was tested by spotting on plain paper and printing on plain paper using a Hewlett-Packard 550C Desk Jet printer. The ink displayed PYt Pl 1Pnt water fastness and no bleeding.
This experiment was repeated by replacing ammonia with methylamine, dimethylamine, trimethylamine, ethylamine, ethano1amine, 3-amino-1,2-propA nPfliol, propanolamine and diethanol amine, giving rise to comparable water-fast ink compositions.
~YA le 48 An ink formulation was prepared containing 30 wt. ~6 Joncryl 90 resin (S. C. Johnson & Sons), 45 . 25 wt. %
deionized water, 0.15 wt.% triacetin, 0.15 wt.96 2t8744 W095/27759 ~ ` I'~IIL e/0~160 pyrr~ nonp~ 0.10 wt.% imidazole, 3.0 wt.% isopropyl alcohol, 6.0 wt.% polyethylene glycol 2000, 15.0 wt.%
~lostafine TS (Hoechst Celanese), 0.15 wt.% Surfynol lOAE
and 0.30 wt.% Surfynol DF-75 tAir Products & Chemicals).
5 The formulation was found to have PY~'PllPnt water fastnes6 and displayed no bleeding after application to a plain paper substrate.

Claims (46)

We claim:

1. An ink composition comprising an aqueous liquid vehicle, an effective amount of a colorant, a binder material comprising a polymeric resin having acidic or basic groups and which ionically or physically entraps the colorant, wherein the binder material is water soluble or rendered water soluble by neutralization with a neutralizing composition, and further wherein the composition is substantially free of monomeric organic solvents and becomes insoluble in water after drying on a substrate.

2. The ink composition of claim 1, wherein the binder material is a polymeric resin having acidic groups, and the neutralizing composition comprises a volatile organic base in an amount effective to provide a solution of 1 wt. % to 50 wt. % of the resin in the aqueous liquid vehicle.

3. The ink composition of claim 2, wherein the neutralizing composition further comprises a nonvolatile organic base.

4. The ink composition of claim 3, wherein the nonvolatile organic base is selected from the group consisting of mono-, di- or tri-substituted lower alkyl amines, diamines having the formula H2N-R8-NH2 wherein R8 is lower alkylene or phenylene, polymeric amines, polymeric imines and heterocyclic amines.

5. The composition of claim 3, wherein the nonvolatile organic base is imidazole.

6. The ink composition of claim 2, wherein the acidic groups are carboxylic acid groups.

7. The ink composition of claim 6, wherein the polymeric resin is a polyacrylate.

8. The ink composition of claim 1, wherein the colorant is selected from the group consisting of dyes, pigments and stains.

9. The ink composition of claim 7, wherein the colorant has ionizable functionalities enabling ionic entrapment thereof by the binder material.

10. The ink composition of claim 1, having a pH in the range of approximately 4 to 9.

11. The ink composition of claim 1, having a pH in the range of approximately 5 to 8.

12. The ink composition of claim 1, having a viscosity in the range of approximately 1.5 to 15 cP, such that the ink composition is useful as a jet printing ink.

13. The ink composition of claim 12, further including 0.1 wt.% to 20 wt.% polyethylene glycol.

14. The ink composition of claim 1, wherein the binder, colorant and aqueous liquid vehicle in combination represent at least about 90 wt. % of the total ink composition.

15. The ink composition of claim 1, having a viscosity of less than about 2.5 cP, such that the ink composition is useful in conjunction with pc printers.

16. The ink composition of claim 1, containing approximately 1 wt.% to 50 wt.% binder material and 0.1 wt.% to approximately 20 wt.% colorant.

17. The ink composition of claim 1, further including an effective moisture-retaining amount of a humectant.

18. The ink composition of claim 17, wherein the humectant is selected from the group consisting of triacetin, N-methyl pyrrolidone and glycerol.

19. The ink composition of claim 1, further including an effective antifoaming amount of an antifoaming agent.

20. The ink composition of claim 1, further including one or more additives selected from the group consisting of surface tension control agents, viscosity modifiers, preservatives and biocides.

21. The ink composition of claim 1, wherein the binder material comprises a resin containing first mer units having the structural formula (I) and second mer units having the structural formula (II) (I) (II) wherein R1 is a hydrophobic moiety, R2 is an ionic group, Z1 and Z2 are linking moieties, and m and n are independently 0 or 1.

22. The ink composition of claim 21, wherein R1 is selected from the group consisting of:
cyano; lower alkyl esters; unsubstituted monocyclic five-and six-carbon aromatic moieties; monocyclic five- and six-carbon aromatic moieties substituted with 1 to 4 substituents selected from the group consisting of lower alkyl, lower alkoxy, halogen and nitro; unsubstituted monocyclic five- and six-carbon heterocyclic moieties containing 1 to 3 heteroatoms; and monocyclic five- and six-carbon heterocyclic moieties containing 1 to 3 heteroatoms and 1 to 4 substituents selected from the group consisting of lower alkyl, lower alkoxy, halogen and nitro;

R comprises a salt moiety -W+? or -Y?Z+, or a zwitterionic species -A+-L1-B? or -C?-L-D+ wherein W, A
and D are independently either imidazolyl or a quaternary ammonium moiety optionally substituted with alkyl groups, Z is selected from the group consisting of metal cations, imidazolyl and quaternary ammonium moieties optionally substituted with alkyl groups, X, Y, B and C are selected from the group consisting of carboxylate, phosphate and sulfonate, and L1 and L are alkylene linking moieties;
and Z1 and Z are selected from the group consisting of arylene optionally containing 1 to 3 heteroatoms, C6-C18 aralkylene, C1-C12 alkylene, -CO-, -COO-, -CONH- and -NHCO-.

23. The ink composition of claim 22, wherein the resin comprises two or more different mer units having the structural formula (I).

24. The ink composition of claim 22, wherein the resin comprises two or more different mer units having the structural formula (II).

25. The ink composition of claim 23, wherein the resin comprises two or more different mer units having the structural formula (II).

26. The ink composition of claim 22, wherein the resin additionally comprises vinyl-based mer units substituted with a moiety which provides for intramolecular crosslinking.

27. The ink composition of claim 1, wherein the binder material comprises a resin containing first mer units having the structural formulae (IVa) and/or (IVb) and second mer units having the structural formula (V) (IVa) (IVb) (V) wherein R3 is hydrogen or lower alkyl;
R4a and R4b are alkyl;

R5 is an anionic species selected from the group consisting of carboxylate, phosphate and sulfonate;
and R6 is a nitrogen atom present in an imidazolyl group, in a monomeric amine NR74+ wherein the R7 moieties may be the same or different and are either hydrogen or lower alkyl, or in a polymeric amine.

28. The ink composition of claim 27, wherein the resin additionally comprises vinyl mer units substituted with a moiety which provides for intramolecular crosslinking.

29. The ink composition of claim 27, wherein R5 is carboxylate and R6 is imidazolyl.

30. The ink composition of claim 1, wherein the binder material comprises poly imidazolium (acrylate co-acrylic acid).

31. The ink composition of claim 1, wherein the binder material comprises poly ammonium (acrylate-co-acrylic acid).

32. The ink composition of claim 1, further including a cross-linking agent.

33. The ink composition of claim 32, wherein the cross-linking agent is selected from the group consisting of imidazole, imidazole substituted with 1 to 3 lower alkyl and/or amino substituents, polyethyleneimines, polyvinylimidazole, polyvinylpyridine, and polyaminosiloxanes.

34. The ink composition of claim 1, wherein the binder material comprises a resin containing first mer units having the structure (VI) and second mer units having the structure (VII) or (VIIII) (VI) --CH2--CH2--NH--(VII) --CH2--CH2--NR8_ (VIII) --CH2--CH(COOH)--wherein, in structure (VII), R8 represents hydrogen, alkyl of 3 to 16 carbon atoms, or lower acyl -(CO)-R9 where R9 is lower alkyl.

35. The ink composition of claim 1, wherein the binder material comprises a resin having a backbone containing at least one polyethylene glycol linkage containing 2 to 500 ethylene glycol units and one or more mer units selected from the group consisting of structures (IX), (X) and (XI) (IX) (X) (XI) wherein R10 is -COOH or -NH2, x is 0 to 4, and y is o or

36. An ink composition comprising an aqueous liquid vehicle, an effective amount of a colorant, and a binder material which ionically or physically entraps the colorant, wherein the binder material comprises at least two polymeric resins which are water soluble or rendered water soluble upon neutralization with a neutralizing composition, and further wherein the composition is substantially free of monomeric organic solvents and becomes insoluble in water after drying on a substrate.

37. The ink composition of claim 37, wherein at least one of the polymeric resins is ionizable in a manner which yields anionic moieties and at least one other of the polymeric resins is ionizable in a manner which yields cationic moieties.

38. An ink composition comprising an aqueous liquid vehicle, an effective amount of a colorant, and a binder material which ionically or physically entraps the colorant, wherein the binder material comprises a polymeric resin and a monomeric material ionically associated therewith, one of which is ionizable in a manner which yields anionic moieties and the other of which is ionizable in a manner which yields cationic moieties, and further wherein the composition is substantially free of monomeric organic solvents and becomes insoluble in water after drying on a substrate.

39. The ink composition of claim 38, wherein the polymeric material contains acidic groups and the monomeric material is an amine selected from the group consisting of mono-, di- or tri-substituted lower alkyl amines, diamines having the formula H2N-R8-NH2 wherein R8 is lower alkylene or phenylene, polymeric amines, polymeric imines and heterocyclic amines.

40. An ink composition comprising an aqueous liquid vehicle, an effective amount of a colorant, and a binder material which ionically or physically entraps the colorant, wherein the binder material comprises a first monomeric material and a second monomeric material ionically associated therewith, one of which is ionizable in a manner which yields anionic moieties and the other of which is ionizable in a manner which yields cationic moieties, and further wherein the composition is substantially free of monomeric organic solvents and becomes insoluble in water after drying on a substrate.

41. The ink composition of claim 40, wherein the first monomeric material is a di- or polyacid and the second monomeric material is a di- or polyamine.

42. The ink composition of claim 41, wherein the first monomeric material is selected from the group consisting of citric acid, tartaric acid, glutaric acid, gluconic acid and benzene tetracarboxylic acid, and the second monomeric material is selected from the group consisting of hexamethylene tetraamine, triethylene tetraamine, ethylene diamine, diethylene triamine, tetraethylene pentamine, pentaethylene hexamine, tris(2-aminoethyl)amine, 1,1,4,7,10,10-hexamethyltriethylene tetramine, and amines containing one to three lower alkyl substitutents.

43. A resin comprised of first mer units having the structural formula (I) and second mer units having the structural formula (II) (I) (II) wherein R1 is selected from the group consisting of:
cyano; lower alkyl esters; unsubstituted monocyclic five-and six-carbon aromatic moieties; monocyclic five- and six-carbon aromatic moieties substituted with 1 to 4 substituents selected from the group consisting of lower alkyl, lower alkoxy, halogen and nitro; unsubstituted monocyclic five- and six-carbon heterocyclic moieties containing 1 to 3 heteroatoms; and monocyclic five- and six-carbon heterocyclic moieties containing 1 to 3 heteroatoms and 1 to 4 substituents selected from the group consisting of lower alkyl, lower alkoxy, halogen and nitro;
R2 comprises an ionic species -W+X- or -Y-Z+ or a zwitterionic species -A+-L1-B- or -C--L-D+
wherein W, Z, A and D are independently either imidazolyl or a quaternary ammonium moiety optionally substituted with alkyl groups, X, Y, B and C are selected from the group consisting of carboxylate, phosphate and sulfonate, and L1 and L2 are alkylene linking moieties;
Z1 and Z2 are linking groups selected from the group consisting of arylene optionally containing 1 to 3 heteroatoms, C6-C18 aralkylene, C1-C12 alkylene, -CO-, -COO-, -CONH- and -NHCO-; and m and n are independently 0 or 1.

44. A resin comprised of first mer units having the structural formulae (IVa) and/or (IVb) and second mer units having the structural formula (V) (IVa) (IVb) (V) wherein:
R3 is hydrogen or lower alkyl;
R4 is lower alkyl;
R5 is an anionic species selected from the group consisting of carboxylate, phosphate and sulfonate;
and R6 is a nitrogen atom present in an imidazolyl group, in a monomeric amine NR74+ wherein the R7 moieties may be the same or different and are hydrogen or lower alkyl, or in a polymeric amine.

45. A resin comprised of first mer units having the structure (VI) and second mer units having the structure (VII) or (VIIII) (VI) ?CH2?CH2?NH?

(VII) --CH2--CH2--NR8--(VIII) --CH2--CH(COOH)--wherein, in structure (VII), R8 represents hydrogen, alkyl of 3 to 16 carbon atoms, or lower acyl -(CO)-R9 where R9 is lower alkyl.

46. A resin having a backbone containing at least one polyethylene glycol linkage containing 2 to 500 ethylene glycol units and one or more mer units selected from the group consisting of structures (IX), (X) and (XI) (IX) (X) (XI) wherein R10 is -COOH or -NH2, x is 0 to 4, and y is 0 or 1.