CA2341113A1 - Phase change inks - Google Patents

Abstract

Disclosed is an ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher.

Description

.r PHASE CHANGE INKS
BACKGROUND OF THE INVENTION
The present invention is directed to phase change ink compositions. More specifically, the present invention is directed to phase change ink compositions particularly suitable for use in acoustic ink jet printing processes that exhibit improved surface hardness subsequent to being jetted onto a substrate and cooled. One embodiment of the present invention is directed to an ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher.
Acoustic ink jet printing processes are known. In acoustic ink jet printing processes, an acoustic beam exerts a radiation pressure against objects upon which it impinges. Thus, when an acoustic beam impinges on a free surface (i.e., liquid/air interface) of a pool of liquid from beneath, the radiation pressure which it exerts against the surface of the pool may reach a sufficiently high level to release individual droplets of liquid from the pool, despite the restraining force of surface tension. Focusing the beam on or near the surface of the pool intensifies the radiation pressure it exerts for a given amount of input power. These principles have been applied to prior ink jet and acoustic printing proposals. For example, K. A. Krause, "Focusing Ink Jet Head," IBM Technical Disclosure Bulletin, Vol. 16, No. 4, September 1973, pp. 1168-1170, the disclosure of which is totally incorporated herein by reference, describes an ink jet in which an acoustic beam emanating from a concave surface and confined by a conical aperture was used to propel ink droplets out through a small ejection orifice.
Acoustic ink printers typically comprise one or more acoustic radiators for illuminating the free surface of a pool of liquid ink with respective acoustic beams. Each of these beams usually is brought to focus at or near the surface of the reservoir (i.e., the liquid/air interface). Furthermore, printing conventionally is performed by independently modulating the excitation of the acoustic radiators in accordance with the input data samples for the image that is to be printed. This modulation enables the radiation pressure which each of the beams exerts against the free ink surface to make brief, controlled excursions to a sufficiently high pressure level for overcoming the restraining force of surface tension. That, in turn, causes individual droplets of ink to be ejected from the free ink surface on demand at an adequate velocity to cause them to deposit in an image configuration on a nearby recording medium. The acoustic beam may be intensity modulated or focused/defocused to control the ejection timing, or an external source may be used to extract droplets from the acoustically excited liquid on the surface of the pool on demand. Regardless of the timing mechanism employed, the size of the ejected droplets is determined by the waist diameter of the focused acoustic beam. Acoustic ink printing is attractive because it does not require the nozzles or the small ejection orifices which have caused many of the reliability and pixel placement accuracy problems that conventional drop on demand and continuous stream ink jet printers have suffered. The size of the ejection orifice is a critical design parameter of an ink jet because it determines the size of the droplets of ink that the jet ejects. As a result, the size of the ejection orifice cannot be increased, without sacrificing resolution. Acoustic printing has increased intrinsic reliability because there are no nozzles to clog. As will be appreciated, the elimination of the clogged nozzle failure mode is especially relevant to the reliability of large arrays of ink ejectors, such as page width arrays comprising several thousand separate ejectors.
Furthermore, small ejection orifices are avoided, so acoustic printing can be performed with a greater variety of inks than conventional ink jet printing, including inks having higher viscosities and inks containing pigments and other particulate components. It has been found that acoustic ink printers embodying printheads comprising acoustically illuminated spherical focusing lenses can print precisely positioned pixels (i.e., picture elements) at resolutions which are sufficient for high quality printing of relatively complex images. It has also been discovered that the size of the individual pixels printed by such a printer can be varied over a significant range during operation, thereby accommodating, for example, the printing of variably shaded images. Furthermore, the known droplet ejector technology can be adapted to a variety of printhead configurations, including (1 ) single ejector embodiments for raster scan printing, (2) matrix configured ejector arrays for matrix printing, and (3) several different types of pagewidth ejector arrays, ranging from single row, sparse arrays for hybrid forms of parallel/serial printing to multiple row staggered arrays with individual ejectors for each of the pixel positions or addresses within a pagewidth image field (i.e., single ejector/pixel/line) for ordinary line printing. Inks suitable for acoustic ink jet printing typically are liquid at ambient temperatures (i.e., about 25°C), but in other embodiments the ink is in a solid state at ambient temperatures and provision is made for liquefying the ink by heating or any other suitable method prior to introduction of the ink into the printhead. Images of two or more colors can be generated by several methods, including by processes wherein a single printhead launches acoustic waves into pools of different colored inks. Further information regarding acoustic ink jet printing apparatus and processes is disclosed in, for example, U.S. Patent 4,308,547, U.S. Patent 4,697,195, U.S. Patent 5,028,937, U.S. Patent 5,041,849, U.S. Patent 4,751,529, U.S. Patent 4,751,530, U.S. Patent 4,751,534, U.S. Patent 4,801,953, and U.S. Patent 4,797,693, the disclosures of each of which are totally incorporated herein by reference. The use of focused acoustic beams to eject droplets of controlled diameter and velocity from a free-liquid surface is also described in J. Appl. Phys., vol. 65, no. 9 (1 May 1989) and references therein, the disclosure of which is totally incorporated herein by reference.
In acoustic ink printing processes, the printhead produces approximately 2.2 picoliter droplets by an acoustic energy process. The ink under these conditions preferably displays a melt viscosity of from about 1 to about 25 centipoise at the jetting temperature. In addition, once the ink has been jetted onto the printing substrate, the image thus generated preferably exhibits excellent crease properties, and is nonsmearing, waterfast, of excellent transparency, and of excellent fix. The vehicle preferably displays a low melt viscosity in the acoustic head while also displaying solid like properties after being jetted onto the substrate. Since the acoustic head can tolerate temperatures typically up to about 180°C, the vehicle for the ink preferably displays liquid-like properties (such as a viscosity of from about 1 to about 25 centipoise) at a temperature of from about 75 to about 180°C, and solidifies or hardens after being jetted onto the substrate such that the resulting image exhibits a hardness value of from about 0.1 to about 0.5 millimeter (measured with a penetrometer according to the ASTM penetration method D1321 ).

Ink jet printing processes that employ inks that are solid at room temperature and liquid at elevated temperatures are known. For example, U.S. Patent 4,490,731, the disclosure of which is totally incorporated herein by reference, discloses an apparatus for dispensing solid inks for printing on a substrate such as paper. The ink vehicle is chosen to have a melting point above room temperature so that the ink, which is melted in the apparatus, will not be subject to evaporation or spillage during periods of nonprinting. The vehicle selected possesses a low critical temperature to permit the use of the solid ink in a thermal ink jet printer.
In thermal ink jet printing processes employing these phase-change inks, the solid ink is melted by a heater in the printing apparatus and used as a liquid in a manner similar to that of conventional piezoelectric or thermal ink jet printing. Upon contact with the printing substrate, the molten ink solidifies rapidly, enabling the dye to remain on the surface instead of being carried into the paper by capillary action, thereby enabling higher print density than is generally obtained with liquid inks. After the phase-change ink is applied to the substrate, freezing on the substrate resolidifies the ink.
In phase-change printing processes, the ink preferably undergoes a change with temperature from a solid state to a liquid state in a desirably short period of time, typically in less than about 100 milliseconds. One advantage of phase-change inks is their ability to print superior images on plain paper, since the phase-change ink quickly solidifies as it cools, and, since it is primarily waxy in nature, it does not normally soak into a paper medium.
Phase-change inks also preferably exhibit a high degree of transparency, generally measured in terms of haze value of the ink.

Transparent, low haze inks exhibit high gloss and high optical density compared to opaque inks, although both may appear to be evenly colored.
The use of phase-change inks in acoustic ink printing processes is also known. U.S. Patent 4,745,419 (Quate et al.), the disclosure of which is totally incorporated herein by reference, discloses acoustic ink printers of the type having a printhead including one or more acoustic droplet ejectors for supplying focused acoustic beams. The printer comprises a carrier for transporting a generally uniformly thick film of hot melt ink across its printhead, together with a heating means for liquefying the ink as it nears the printhead. The droplet ejector or ejectors are acoustically coupled to the ink via the carrier, and their output focal plane is essentially coplanar with the free surface of the liquefied ink, thereby enabling them to eject individual droplets of ink therefrom on command. The ink, on the other hand, is moved across the printhead at a sufficiently high rate to maintain the free surface which it presents to the printhead at a substantially constant level. A variety of carriers may be employed, including thin plastic and metallic belts and webs, and the free surface of the ink may be completely exposed or it may be partially covered by a mesh or perforated layer. A separate heating element may be provided for liquefying the ink, or the lower surface of the carrier may be coated with a thin layer of electrically resistive material for liquefying the ink by localized resistive heating.
U.S. Patent 5,541,627 (Quate), the disclosure of which is totally incorporated herein by reference, discloses a method and apparatus for ejecting droplets from the crests of capillary waves riding on the free surface of a liquid by parametrically pumping the capillary waves with electric fields from probes located near the crests. Crest stabilizers are beneficially used to fix the spatial locations of the capillary wave crests near the probes. The probes are beneficially switchably connected to an AC
voltage supply having an output that is synchronized with the crest motion.
When the AC voltage is applied to the probes, the resulting electric field adds sufficient energy to the system so that the surface tension of the liquid is overcome and a droplet is ejected. The AC voltage is synchronized such that the droplet is ejected about when the electric field is near is minimum value. A plurality of droplet ejectors are arranged and the AC voltage is switchably applied so that ejected droplets form a predetermined image on a recording surface. The capillary waves can be generated on the free surface of the liquid by using acoustical energy at a level approaching the onset of droplet ejection. The liquid used with the invention must also must be attracted by an electric field.
Phase-change inks used in acoustic ink printing processes also preferably exhibit a low acoustic-loss value, typically below about 100 decibels per millimeter. In addition, the ink vehicle preferably can fill the pores of a porous substrate, such as paper, and preferably has a melting point of from about 80 to about 120°C; this melting point, along with low acoustic-loss, enables a minimization of energy consumption. When the phase-change inks are used in an electric field assisted acoustic ink printing process, the inks also are sufficiently conductive to permit the transmission of electrical signals generated by the electric field assisted acoustic ink jet printer; the inks preferably exhibit a conductivity of from about 2 to about 9 log(picomho/cm) (measured under melt conditions at about 150°C by placing an aluminum electrode in the molten ink and reading the resistivity output on a GenRad 1689 precision RLC Digibridge at a frequency of 1 kiloHertz). In general, the conductivity of a material can be measured in terms of the reciprocal of resistivity, which is the capacity for electrical resistance. Further information regarding electric field assisted acoustic ink printing processes is disclosed in, for example, Copending Application U.S.
Serial No. 09/280,717, filed March 30, 1999, entitled "Method and Apparatus for Moving Ink Drops using an Electric Field and Transfuse Printing System Using the Same," with the named inventors John S. Berkes, Vittorio R.
Castelli, Scott A. Elrod, Gregory J. Kovacs, Meng H. Lean, Donald L. Smith, Richard G. Stearns, and Joy Roy, the disclosure of which is totally incorporated herein by reference, which discloses a method of forming and moving ink drops across a gap between a printhead and a print medium or intermediate print medium in a marking device. The method includes generating an electric field, forming the ink drops adjacent to the printhead, and controlling the electric field. The electric field is generated to extend across the gap. The ink drops are formed in an area adjacent to the printhead. The electric field is controlled such that an electrical attraction force exerted on the formed ink drops by the electric field is the greatest force acting on the ink drops. The marking device can be incorporated into a transfuse printing system having an intermediate print medium made of one or more materials that allow for lateral dissipation of electrical charge from the incident ink drops.
"Dynamic Mechanical and Spectroscopic Study of lonomer Blends Based on Carboxylated or Sulfonated Flexible Polystyrene and Rigid Poly(diacetylenes) with Functional Side Groups," C.D. Eisenbach et al., Macromolecules, Vol. 27, p. 3162 (1994), the disclosure of which is totally incorporated herein by reference, discloses a study wherein the dynamic mechanical and infrared spectroscopic investigation of ionomer blends of poly(diacetylene)- and polystyrene-based ionomers has shown that miscibility of this usually incompatible polymer pair can be achieved through ion-ion interactions between the blend components. Microphase separation is prevented through ionic contacts generated during the blend formation. A schematic model of mixing in the blends is proposed.
"Statistical Thermodynamics of Mixtures of Rodlike Particles. 5.
Mixtures with Random Coils," Paul J. Flory, Macromolecules, Vol. 11, no. 6, p. 1138 (1978), the disclosure of which is totally incorporated herein by reference, discloses a study wherein ternary systems consisting of a solvent, a rigid rod solute, and a randomly coiled polymer chain are treated according to a specific model and procedures. Phase equilibria are calculated for systems specified by (xZx3)=(10,10), (20,20), (20,~), and (100,100), where x2 and x3 are the molar volumes of the respective solutes relative to the solvent. Addition of the randomly coiled polymer chain to the binary system of solvent and solute increases the volume fraction v2' of the rodlike solute in the anisotropic phase and broadens the biphasic gap.
The preponderance of the randomly coiled polymer chain is retained by the isotropic phase. Its volume fraction v3' in the anisotropic phase is <10-4 for all compositions and becomes vanishingly small if v2' is much increased by raising v3 in the isotropic phase. The isotropic phase exhibits a somewhat greater tolerance for the rodlike component. For large values of xz and v3, however, vz becomes negligible. The marked segregation of these components between the two phases underscores the basic differences in their mixing tendencies.
Many phase change inks lack surface hardness after deposition on a substrate and cooling. The resulting images are thus susceptible to smearing. When addressing this issue, it is also desirable to do so in a way that does not undesirably affect the bulk viscosity of the ink. Increasing bulk viscosity is a major concern for phase change inks because the power required to eject droplets is strongly dependent on the ink bulk viscosity, with higher ink viscosities requiring more ejection power.
Accordingly, while known compositions and processes are suitable for their intended purposes, a need remains for improved phase change inks. In addition, a need remains for phase change inks particularly suitable for use in acoustic ink jet printing processes. Further, a need remains for phase change inks that exhibit improved surface hardness subsequent to being ejected onto a substrate and cooled. Additionally, a need remains for phase change inks with desirable bulk viscosities. There is also a need for phase change inks that exhibit good smear resistance subsequent to being ejected onto a substrate and cooled. In addition, there is a need for phase change inks that exhibit low haze subsequent to being ejected onto a substrate and cooled.
SUMMARY OF THE INVENTION
The present invention is directed to an ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher. Another embodiment of the present invention is directed to a printing process which comprises incorporating into an ink jet printing apparatus an ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher, melting the ink, and causing droplets of the melted ink to be ejected in an imagewise pattern onto a recording sheet. In a preferred embodiment, the printing apparatus employs an acoustic ink jet process, wherein droplets of the ink are caused to be ejected in imagewise pattern by acoustic beams.
DETAILED DESCRIPTION OF THE INVENTION
The inks of the present invention contain an ink vehicle. The ink vehicle is present in the ink in any desired or effective amount, typically at least about 50 percent by weight of the ink, and preferably at least about 60 percent by weight of the ink, and typically no more than about 98 percent by weight of the ink, preferably no more than about 92 percent by weight of the ink, and more preferably no more than about 85 percent by weight of the ink, although the amount can be outside of these ranges. The ink vehicle typically has a melting point of no less than about 60°C, preferably no less than about 65 ° C, and more preferably no less than about 70 °
C, and typically has a melting point of no more than about 150°C, preferably no more than about 135°C, and more preferably no more than about 100°C, although the melting point can be outside of these ranges. Preferably, the ink vehicle has an acoustic-loss value of no more than about 100 decibels per millimeter, although the acoustic-loss value can be outside of this range.
Typically, the ink vehicle has a hardness value of at least about 60, although the hardness value can be outside of this range.
Any desired or suitable hot melt ink vehicle can be employed.
Specific examples include low molecular weight polyamides, polyesteramides, block copolymers of polyamides of polyesteramides, polyethylene, polypropylene, copolymers and block copolymers of polyethylene and polypropylene, carbamates and biscarbamates of the generic formula C"H2~+~ -NHC00-CnHz"+t and C~H2"+~-OCONH-C"H2"-NHC00-C"H2"+~ wherein n is an integer typically of from about 5 to about 20 and selected to provide materials that are solid at room temperature, low molecular weight alkylated ureas and bis-ureas in which the alkyl groups typically have from about 5 to about 20 carbons with the number of carbon atoms selected to provide materials that are solid at room temperature, and the like, as well as mixtures thereof.
Also suitable are primary and secondary monoamides, including primary mono-amides such as stearamide (KEMAMIDEO S, available from Witco Chemical Company, Memphis, TN), secondary mono-amides such as behenyl benenamide (KEMAMIDEO EX--666, available from Witco), stearyl stearamide (KEMAMIDEO S-180, available from Witco), and the like, as well as mixtures thereof.
Also suitable are (I) conductive nonpolymeric pyridinium compounds, such as those of the general formula Rs / R5 An O
R ~ N R6 n wherein each of R~, RZ, R3, R4, R5, and R6, independently of the others, can be (but are not limited to) hydrogen atoms, alkyl and alkoxy groups, including saturated, unsaturated, branched, linear, and cyclic alkyl and alkoxy groups (typically with from 1 to about 30 carbon atoms, although the o r CA 02341113 2001-03-16 number of carbon atoms can be outside of this range), including substituted and unsubstituted alkyl and alkoxy groups, aryl and aryloxy groups (typically with from 6 to about 30 carbon atoms, although the number of carbon atoms can be outside of this range), including substituted and unsubstituted aryl and aryloxy groups, arylalkyl, arylalkyloxy, alkylaryl, and alkylaryloxy groups (typically with from 7 to about 30 carbon atoms, although the number of carbon atoms can be outside of this range), including substituted and unsubstituted arylalkyl, arylalkyloxy, alkylaryl, and alkylaryloxy groups, heterocyclic groups (typically with from about 5 to about 10 ring atoms, wherein the hetero atoms can be (but are not limited to) oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, and the like), including substituted and unsubstituted heterocyclic groups, hydroxy groups, amine groups, imine groups, ammonium groups, pyridine groups, pyridinium groups, ether groups, ester groups, amide groups, carbonyl groups, thiocarbonyl groups, sulfate groups, sulfonate groups, sulfide groups, sulfoxide groups, phosphine groups, phosphonium groups, phosphate groups, mercapto groups, nitroso groups, sulfone groups, acyl groups, acid anhydride groups, azide groups, and the like, wherein two or more substituents can be joined together to form a ring, wherein the substituents on the substituted alkyl, alkoxy, aryl, aryloxy, arylalkyl, arylalkyloxy, alkylaryl, alkylaryloxy, and heterocyclic groups can be (but are not limited to) hydroxy groups, amine groups, imine groups, ammonium groups, pyridine groups, pyridinium groups, ether groups, ester groups, amide groups, carbonyl groups, thiocarbonyl groups, sulfate groups, sulfonate groups, sulfide groups, sulfoxide groups, phosphine groups, phosphonium groups, phosphate groups, mercapto groups, nitroso groups, sulfone groups, acyl groups, acid anhydride groups, azide groups, and the like, A is any desired - " CA 02341113 2001-03-16 or suitable anion, with examples of anions including (but not limited to) Cl-, Br , ~ , HS04 , HS03 , SO42 , SO32 , CHZS03 , CH3SO3 , CH3C6H4SO3 , N03 , HC00 , CH3C00~, HC03-, C032~, HZP04 , HP042-, PO43-, SCN-, BF4 , C104-, SS03-, and the like, as well as mixtures thereof, and n is an integer; n typically is 1, 2, or 3, but when the anion is polymeric, the value of n is not limited; examples of suitable conductive pyridinium compounds include (1) 1-propyl pyridinium salts, such as 1-propyl pyridinium bromide (Aldrich 41,288-0), of the formula Bra V

(2) 1-ethyl-3-hydroxy pyridinium salts, such as 1-ethyl-3-hydroxy pyridinium bromide (Aldrich 19,264-3), of the formula OH
~N Bra (3) 1-ethyl-4-phenyl pyridinium salts, such as 1-ethyl-4-phenyl pyridinium iodide (Aldrich 36,208-5), of the formula / to ~J
~N

(4) 1-ethyl-4-(methoxy carbonyl) pyridinium salts, such as 1-ethyl-4-(methoxy carbonyl) pyridinium iodide (Aldrich 32,625-9), of the formula H3C~C~0 I
~ V

(5) pyridinium 3-nitrobenzene sulfonate (Aldrich 27,198-5), of the formula o SO3 ~J
~N
H ~ N02 (6) pyridinium-p-toluene sulfonate (Aldrich 23,223-8), (7) pyridinium trifluoroacetate (Aldrich 21,513-9), (8) 1-heptyl-4-(4-pyridyl) pyridinium salts, such as 1-heptyl-4-(4-pyridyl) pyridinium bromide (Aldrich 37,778-3), of the formula CH3(CH2)5CH2-Br~
(9) cetyl pyridinium salts, such as cetyl pyridinium bromide monohydrate (Aldrich 28,531-5), of the formula . , CA 02341113 2001-03-16 / OH

Br ~
~H2(CH2)14CH3 and cetyl pyridinium chloride monohydrate (Aldrich 85,556-1), (10) 1-dodecyl pyridinium salts, such as 1-dodecyl pyridinium chloride hydrate (Aldrich 27,860-2), of the formula / ~ . H2O
CI~
CH2(CH2)1 oCH3 and the tike, as well as mixtures thereof; (II) 1,3-dialkyl ureas, including those of the general formula CH3(CH2)~NHCONH(CH2)~CH3, wherein n is an integer typically of from about 5 to about 20, such as 1,3-dioctadecyl urea (Aldrich 32,803-0), wherein n is 17, and the like; (III) N,N'-ethylene bisalkylamides, wherein the alkyl groups can be saturated or unsaturated, including those of the general formula (CH3(CHZ)"CH=CH(CH2)"CONHCH2-)z, wherein n is an integer typically of from about 5 to about 20, such as N,N'-ethylene bisoleamide (Atdrich 43,466-3), wherein n is 7, and those of the general formula (CH3(CHZ)~CHCONHCH2-)2, wherein n is an integer typically of from about 5 to about 20, such as N,N'-ethylene bisstearamide, wherein n is 16, and the like; (IV) N-(4-chloro-3-(4,5-dihydro-5-oxo-1-(2,4,6-trichlorophenyl)-1 H-pyrazol-3-ylamino) phenyl)-2-(1-octadecenyl) succinimide (Aldrich 38,582-4); (V) 1,3-diamino-5,6-bis(octyloxy) isoindoline (Aldrich 46,218-7); (VI) N,N-dimethyl alkylamine N-oxides, including those of the general formula CH3(CH2)"N(CH3)Z0, wherein n is an integer typically of from about 5 to about 20, such as N,N-dimethyl heptylamine N-oxide hydrate (Aldrich 38,250-7), wherein n is 6, N,N-dimethyl octylamine N-oxide hydrate (Aldrich 36,568-8), wherein n is 7, N,N-dimethyl nonylamine N-oxide hemihydrate (Aldrich 38,252-3), wherein n is 8, N,N-dimethyl undecyl amine N-oxide (Aldrich 38,253-1 ), wherein n is 10, N,N-dimethyl dodecyl amine N-oxide (Aldrich 28,970-1), wherein n is 11, and the like; (VII) alkyl amides, wherein the alkyl portion can be saturated or unsaturated, including those of the general formula CH3(CH2)~CH=CH(CH2)mCONH2, wherein m and n are each integers the sum of which typically is from about 5 to about 20, such as erucamide (Aldrich 28,057-7), wherein n is 7 and m is 11, and those of the general formula CH3(CH2)"CONHz, wherein n is an integer typically of from 0 to about 20, such as acetamide (Aldrich 12,263-7), wherein n is 0, propionamide (Aldrich 14,393-6), wherein n is 1, hexanoamide (Aldrich 29,339-3), wherein n is 4, octadecanamide (Aldrich 0-60-1), wherein n is 16, or the tike; (VIII) polymeric anhydrides, such as (1 ) poly (sebacic anhydride) (Aldrich 45,832-5), (2) poly (azelaic anhydride) (Aldrich 45,831-7), (3) poly (malefic anhydride-alt-1-tetradecene (Aldrich 45,251-3), (4) polyethylene-graft-malefic anhydride with 0.5 weight percent malefic anhydride (Aldrich 45,662-4), (5) poly(ethylene-co-butylacrylate-co-malefic anhydride) with 91 weight percent ethylene, 5.5 weight percent butyl acrylate, and 3.5 weight percent malefic anhydride (Aldrich 43,085-4), (6) poly(maleic anhydride-alt-a-olefin, wherein the olefin typically has from about 24 to about 28 carbon atoms (Aldrich 45,262-95), and the like; (IX) aldehyde copolymers, including copolymers of aldehyde monomers, such as formaldehyde and the like and other monomers, with specific examples of suitable aldehyde copolymers including (1 ) poly ((phenyl glycidyl ether)-co-formaldehyde) (Aldrich 40,676-7), of the formula O O O
~H2 I H2 ~H2 \ \ \

/ / n /
(2) poly ((o-cresyl glycidyl ether)-co-formaldehyde) (Aldrich 40,551-5), of the formula O O O
I H2 I H2 , H2 \ CH3 \ CH3 \

n (3) poly (p-toluenesulfonamide-co-formaldehyde) (Aldrich 28,076-3), and the like; (X) nonpotymeric aromatic compounds, including (1 ) 4-hexyl resorcinol (Aldrich 20,946-5), (2) 4-dodecyl resorcinol (Aldrich D22,260-7), (3) 4-(tert-octyl) phenol (Aldrich 29,082-3), (4) 4-bromo-N-dodecyl-1-hydroxy-2-naphthalene carboxamide (Aldrich 37,157-2), (5) 2,2-Biphenyl-1,4-diazaspiro-(4, 5)deca-1, 3-diene (Aldrich 37,146-7), (6) N, N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane (Aldrich 29,472-1 ), (7) 1,4-dihydro-9-isopropylidene-1,4-methanonaphthalene (Aldrich 43,201-6), (8) 1,4,4a,8a-tetrahydro-endo-1,4-methanonaphthalene (Aldrich 34,180-0), (9) 1, 5-dihydroxy-1,2,3,4-tetrahydronaphthalene (Aldrich 10,915-0), (10) 2,5-difluorophenylhydrazine (Atdrich 32,419-1 ), and the like; (XI) nonpolymeric ketones, including (a) alkyl alkyl ketones, including those of the general formula R-(C=0)-R' wherein R and R' each, independently of the other, is an alkyl group, including linear, branched, cyclic, saturated, unsaturated, and substituted alkyl groups, typically with from 1 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, with specific examples including (1 ) n-octyl-n-propyl ketone (ICN #213357), (2) n-octyl-n-butyl ketone (ICN #206848), (3) n-decyl-n-ethyl ketone (ICN #204911 ), (4) n-undecyl-n-propyl ketone (ICN #207355), (5) n-dodecyl-n-ethyl ketone (ICN
#209666), (6) di-n-hexylketone (ICN #215620), (7) di-n-heptylketone (ICN
#209745), (8) di-n-octyl ketone (ICN #204765), (9) di-n-nonyl ketone (ICN
#212765), (10) di-n-decyl ketone (ICN #215139), (11 ) di-n-undecyl ketone (ICN #203303), (12) di-n-tridecyl ketone (ICN #213235), (13) di-n-heptadecyl ketone (ICN #201684), (14) di-n-octadecyl ketone (ICN #201684), and the like, as well as mixtures thereof, (b) alkyl aryl ketones, including those of the general formula R-(C=0)-Ar wherein R is an alkyl group, including linear, branched, cyclic, saturated, unsaturated, and substituted alkyl groups, typically with from 1 to about 20 carbon atoms, although the number of carbon atoms can be outside of this range, and Ar is an aryl group, including substituted aryl groups, typically with from 6 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, such as phenyl, naphthyl, anthryl, or the like, with specific examples including (1 ) n-octyl phenyl ketone (obtained from ICN Biomedical; ICN #204935), (2) n-undecyl phenyl ketone (ICN #217796), (3) n-pentadecyl phenyl ketone (ICN #225428), (4) n-octadecyl phenyl ketone (available as #00185 from TCI America), and the like, as well as mixtures thereof, (c) aryl aryl ketones, including those of the general formula Ar-(C=0)-Ar' wherein Ar and Ar' each, independently of the other, is an aryl group, including substituted aryl groups, typically with from 6 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, such as phenyl, naphthyl, anthryl, or the like, with specific examples including (1 ) diphenyl acetone (ICN #208157, ICN #206354), (2) 2-naphthyl phenyl ketone (available as #B0301 from TCI America), and the like, as well as mixtures thereof, (d) aryl arylalkyl ketones and aryl alkylaryl ketones, including those of the general formulae Ar-(C=0)-RAr' and Ar-(C=0)-Ar'R
wherein Ar and Ar' each, independently of the other, is an aryl group, including substituted aryl groups, typically with from 6 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, such as phenyl, naphthyl, anthryl, or the like, and R is an alkyl group, including linear, branched, cyclic, saturated, unsaturated, and substituted alkyl groups, typically with from 1 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, with specific examples including (1 ) benzyl phenyl ketone (ICN #202318) and the like, (e) arylalkyl arylalkyl ketones, arylalkyl alkylaryl ketones, and alkylaryl alkylaryl ketones, including those of the general formulae . CA 02341113 2001-03-16 ArR-(C=0)-Ar'R' ArR-(C=0)-R'Ar' RAr-(C=0)-R'Ar' wherein Ar and Ar' each, independently of the other, is an aryl group, including substituted aryl groups, typically with from 6 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, such as phenyl, naphthyl, anthryl, or the like, and R and R' each, independently of the other, is an alkyl group, including linear, branched, cyclic, saturated, unsaturated, and substituted alkyl groups, typically with from 1 to about 25 carbon atoms, although the number of carbon atoms can be outside of this range, with examples of suitable substituents on the substituted alkyl, aryl, arylalkyl, and alkylaryl groups including (but not being limited to) hydroxy groups, amine groups, imine groups, ammonium groups, pyridine groups, pyridinium groups, ether groups, ester groups, amide groups, carbonyl groups, thiocarbonyl groups, sulfate groups, sulfonate groups, sulfide groups, sulfoxide groups, phosphine groups, phosphonium groups, phosphate groups, mercapto groups, nitroso groups, sulfone groups, acyl groups, acid anhydride groups, azide groups, and the tike, with specific examples of suitable ketones including (1 ) di-n-benzyl ketone (obtained from ICN Biomedicals; ICN #208157) and the like; (XII) polyesters, including homopolymers of ester monomers and copolymers of ester monomers and other monomers, with examples of suitable polyesters including (1 ) poly(hexamethylene sebacate) (#124 Scientific Polymer Products), (2) poly(1,6-hexamethylene adipate) (Aldrich 45,836-8), (3) polyvinyl acetate) (Aldrich 43,043-9), (4) polyvinyl cinnamate) (Aldrich 18,264-8), (5) polyvinyl stearate) (Aldrich 18,279-68), (6) polyethylene succinate (Aldrich 18,203-6), (7) polyethylene terephthalate (Vitel 5833, available from Shell Chemical Co.), (8) poly(vinylacetate-co-crotonic acid) (Aldrich 44,467-7), (9) sucrose octaacetate (Aldrich 25,260-3), (10) poly(di(ethyleneglycol)/cyclohexanedimethanol-alt-isophthalic acid, sulfonated) (Aldrich 45,871-6), and the like; (XIII) carbamates, such as (1 ) butyl carbamate (Aldrich B9,080-7); (2) tert-butyl carbamate (Aldrich 16,739-8); (3) tert-butyl N-(3-aminopropyl) carbamate (Aldrich 43,699-2);
(4) tert-butyl N-(3-hydroxypropyl) carbamate (Aldrich 41,644-4); (5) tert-butyl-N-(benzytoxy)-carbamate (Atdrich 40,769-0); (6) tert-butyl-N-hydroxycarbamate (Aldrich 22,615-7); (7) tert-butyl-N-allylcarbamate (Aldrich 42,233-9); (8) tert-butyl-N-(tert-butoxycarbonyloxy) carbamate (Aldrich 41,279-1); (9) tert-butyl-N-(2-hydroxy-2-(hydroxyphenyl)-1-methylethyl) carbamate (Aldrich 40,429-2); (10) tert-butyl-(2,4-dinitrophenoxy) carbamate (Aldrich 33,305-0); (11 ) benzyl carbamate (Alfa Organics #A11569); (12) benzyl N-hydroxycarbamate (Aldrich 32,327-6); (13) benzyl N-(2-hydroxyethyl)carbamate (Aldrich 40,790-9); (14) benzyl-N,N-dimethyldithiocarbamate (Aldrich 36,822-9); (15) ethyl N-methyl-N-phenylcarbamate (Aldrich 30,951-6); (16) ethyldiphenyl carbamate (Aldrich 37,291-9); (17) cyanomethyt-N,N-dimethyt dithiocarbamate (Aldrich 28,054-2); (18) 4,4'-methylene-bis(dibutyldithio carbamate) (Vanlube 7723, Vanderbilt Corporation); (19) potassium N-hydroxy methyl-N-methyl-dithiocarbamate (Busan 40 from Buckman Laboratories Inc.); (20) sodium dimethyl dithiocarbamate; (21 ) disodium ethylenebis-dithio carbamate; (22) diethylammonium diethyldithio carbamate (Alfa Organics #A10458); (23) benzyl(S)-(-)-tetrahydro-5-oxo-3-furanyl carbamate (Aldrich 41,924-9); (24) diethyldithiocarbamic acid, ammonium salt (Aldrich 35,954-8); (25) diethyldithiocarbamic acid, diethyl ammonium salt (Aldrich 31,811-6); (26) diethyldithiocarbamic acid, sodium salt, trihydrate (Aldrich 22,868-0); (27) 4-bromo-3,5-dimethylphenyl N-methylcarbamate (Aldrich 34,694-2); (XIV) thioureas, such as (1) 1-allyl-2-thiourea (Aldrich 10,880-41); (2) 1-allyl-3-(2-hydroxyethyl)-2-thiourea (Aldrich A3,280-2); (3) 1-methyl-2-thiourea (Aldrich M8,460-7); (4) 1-methallyl-3-methyl-2-thiourea (Aldrich 19,046-2); (5) 1,3-dibutyl-2-thiourea (Aldrich D4,959-8); (6) 1,1,3,3-tetramethyl-2-thiourea (Aldrich 11,516-9); (7) N,N'-di-n-propyl thiourea (Alfa Organics #A17217); (8) 1-benzyl-3-methyl-2-thiourea (Atdrich 27,550-6); and the like; (XV) alcohols, such as (A) cyclic alcohols, such as (1 ) cycloalkyl alcohols where the number of carbons in the alkyl chain vary, for example, from 1, preferably from about 6 to about 12 and more preferably from about 8 to about 10, such as cyclohexanol (Aldrich 10,589-9), cycloheptanol (Aldrich C9,880-2), cyclododecanol, (Aldrich C9,740-7); (2) 4-tert-butyl cyclohexanol (Aldrich 89,200-1 ); (3) 3-aminomethyl-3,5,5-trimethyl cyclohexanol (Aldrich 19,479-4); (4) 2,2,6,6-tetrachloro cyclohexanol, (Aldrich 18,681-3); (5) cycloalkane methanol where the number of carbons in the alkane chain is for example, from about 5 to about 12 and preferably between about 8 to about 11, such as cyclopentane methanol (Aldrich 10,398-5), cyclohexane methanol (Aldrich C10,580-5), cycloheptane methanol (Aldrich 13,865-7), cyclododecane methanol (Aldrich 11,224-0); (6) dicyclohexylmethanol (Aldrich 31,772-1 ); (7) 3-cyclohexyl-1-propanol (Aldrich 30,440-9); (8) 2-amino-3-cyclohexyl-1-propanol (Aldrich 42,161-8); (9) (S)-2-(tert-butoxycarbonylamino)-3-cyclohexyl-1-propanol (Aldrich 42,169-3); (10) cycloalkane diol where the number of carbons in the alkane chain is from 5 to about 9 and preferably between about 6 and 8 such as 1,2-cyclopentanediol (Aldrich 36,144-5), 1,3-cyclohexanediol (Aldrich C10,110-9), 1,2-cyclohexane diol (Aldrich 36,126-7;
14,171-2), 1,4-cyclohexane diol (Aldrich C10,120-6), cyclooctanediol (Aldrich 17,903-5; 36,223-9); (11) cis-3,5-cyclohexadiene-1,2-diol (Aldrich 36,506-8);

(12) p-menthane-3,8-diol (Aldrich 38,404-6; 38,405-4); (13) cyclohexane dimethanol (Aldrich 12,559-8; Aldrich 18,908-1 ); (14) 1,3-dioxane-5,5-dimethanol (Aldrich 22,062-0); (15) 3-cyclohexene-1,1-dimethanol (Aldrich 16,215-9); (16) piperidine methanol (Aldrich 15,522-5; Aldrich 15,523-3);
(17) 4,4'-trimethylenebis(1-piperidine ethanol) (Aldrich 12,122-3); (B) linear alcohols, such as (1 ) alkyl alcohols where the number of carbons in the alkyl chain is for example, from about 1, preferably from about 6 about 22 and more preferably between about 12 to about 16 such as hexyl alcohol (Aldrich H1330-3), heptyl alcohol (Aldrich H280-5), octyl alcohol (Aldrich 29,324-5), nonyl alcohol (Aldrich 13,121-0), decylalcohol (Aldrich 23,976-3), undecyl alcohol (Aldrich U100-1), 1-dodecanol (Aldrich 12,679-9), 1-tetra decanol (Aldrich 18,538-8), 1-pentadecanol (Aldrich 41,222-8), 1-hexadecanol (Aldrich 25,874-1 ), 1-eicosanol (Aldrich 23,449-4), 1-docosanol (Aldrich 16,910-2); (2) alkane diols where the number of carbons in the alkane chain is about 5 to about 14 and preferably from about 8 to about 12, such as 1, 5-pentane diol (Aldrich P770-3), 1,6-hexane diol (Aldrich H1,180-7), 1,7-heptane diol (Aldrich H220-1), 1,2-octane diol (Aldrich 21,370-5), 1,8-octane diol (Aldrich 0,330-3), 1,9-nonane diol (Aldrich N2,960-0), 1,10-decane diol (Aldrich D,120-3), 1,2-decane diol (Aldrich 26,032-0), 1,2-dodecane diol (Aldrich 21,372-1), 1,12-dodecane diol (Aldrich D22,130-9), 1,2-tetradecane diol (Aldrich 26,029-0), 1,14-tetradecane diol (Aldrich 29,901-4); (3) di(trimethylol propane) (Aldrich 41,613-4); (4) nitromethane trispropanol (Aldrich 36,153-4); (5) 11-bromo-1-undecanol (Aldrich 18,413-6); (6) 12-bromo-1-dodecanol (Aldrich 22,467-7); (7) 2-methyl-2-propyl-1,3-propane diol (Aldrich M7,520-9); (8) 2,2-diethyl-1,3-propanediol (Aldrich D10,000-5);
(9) (2-(hydroxymethyl)-1,3-propanediol (Aldrich 39,365-7); (10) 2,2,4-trimethyl-1,3-pentanediol (Aldrich 32,722-0); (11) 2-butyne-1,4-diol (Aldrich 810,320-9); (12) (~)-3,6-dimethyl-4-octyne-3,6-diol (Aldrich 27,840-8); (13) 3,6-dithia-1,8-octanediol (Aldrich 23,533-4); (14) 2,4,7,9-tetramethyl-5-decyne-4,7-diol (Aldrich 27,838-6); (C) amino alcohols such as (1 ) 2-(2-aminoethoxy)ethanol (Aldrich A5,405-9); (2) 2-(2-amino ethylamino) ethanol (Aldrich 12,758-2); (3) amino-1-propanol (Aldrich 23,886-4, 29,768-2, 19,217-1, A7,620-6, 23,984-4); (4) 2-amino-1-butanol (Aldrich A4,380-6); (5) 4-amino-1-butanol (Aldrich 17,833-0); (6) 2-amino-3-methyl-1-butanol (Aldrich 18,483-7); (7) 5-amino-1-pentanol (Aldrich 12,304-8); (8) 6-amino-1-hexanol (Aldrich A5,645-0); (9) D,L-2-amino-1-hexanol (Aldrich 23,767-1 ); (10) (S)-(-)-N-(tert-butoxycarbonyl) leucinol (Aldrich 44,119-8); (D) aromatic alcohols, such as (1 ) alkyl benzyl alcohol where the number of carbon atoms in the alkyl group is, for example, from 0 to about 8, and preferably between about 4 and 6, such as benzyl alcohol (Aldrich 10,800-6), 3-methyl benzyl alcohol (Aldrich 18,821-2), 4-methyl benzyl alcohol (Aldrich 12,780-9), 2-phenyl benzyl alcohol (Aldrich 18,882-4), 2-phenethyl benzyl alcohol (Aldrich 18,478-0); (2) alkoxy and aryloxy benzyl alcohols where the number of carbons in the alkoxy groups is for example, from about 1 to about 4 such as 2-methoxy benzyl alcohol (Aldrich M1,080-8), 3-methoxybenzyl alcohol (Aldrich M1,100-6), 4-methoxy benzyl alcohol (Aldrich 13,690-5), 2-ethoxy benzyl alcohol (Aldrich 19,066-7), 4-ethoxy benzyl alcohol (Aldrich 19,047-0), 4-butoxy benzyl alcohol (Aldrich 18,424-1 ), and in the aryloxy groups these vary from 6 to 8 such as 3-benzyloxy benzyl alcohol; (3) alkyl alkyl benzyl alcohols where the number of carbons in each alkyl group varies from about 1 to about 4, such as 2,4-dimethyl benzyl alcohol (Aldrich 18,878-6), 2,5-dimethyl benzyl alcohol (Aldrich 18,932-4), 3,5-dimethyl benzyl alcohol (Aldrich 19,999-0), 3,4-dimethyl benzyl alcohol (Aldrich 18,879-4); (4) 2-amino-3-methyl benzyl alcohol (Aldrich 33,419-7); (5) alkoxy alkoxy benzyl alcohols where the number of carbon atoms in each alkoxy group varies from about 1 to about 4, such as 2,4-dimethoxy benzyl alcohol (Aldrich 15,963-8), 3,5-dimethoxy benzyl alcohol (Aldrich 19,165-5), 2,3-dimethoxy benzyl alcohol (Aldrich 12,631-4), 3-ethoxy-4-methoxy benzyl alcohol (Aldrich 30,790-4), 4-ethoxy-3-methoxy benzyl alcohol (Aldrich 18,914-6); (6) 2-hydroxy-3-methoxy benzyl alcohol (Aldrich 30,596-0); (7) 3,4,5-trimethoxy benzyl alcohol (Aldrich T7,000-9); (E) phenyl alcohol derivatives such as (1 ) phenylpropanol (Aldrich P3,080-2; Aldrich 14,085-6); (2) 3-(4-hydroxy phenyl)-1-propanol (Aldrich 19,741-6); (3) (S)-(-)-1-phenyl-1-butanol (Aldrich 31,731-4); (4) 2-amino-1-phenyl ethanol (Aldrich A7,240-5); (5) 3,4-dimethoxy phenethyl alcohol (Aldrich 19,765-3); (6) 2-phenyl-1,2-propane diol (Aldrich 21,376-4); (7) 3-phenoxy-1,2-propane diol (Aldrich 10, 819-7); (8) 3-methoxy catechol (Aldrich M1,320-3); (9) benzhydrol (Aldrich B,485-4); (10) methyl benzhydrol (Aldrich 18,995-2; Aldrich 18,996-0); (11 ) phenethylalcohol (Aldrich P1,362-2); (12) 4-methoxy phenethyl alcohol (Aldrich 15,418-0); (13) 2-hydroxy phenethyl alcohol (Aldrich 18,824-7; Aldrich 19,902-8); (14) 2-amino phenethylalcohol (Aldrich 19,260-0); and the like; (XVI) oxazolines, such as (1 ) 5-(hydroxymethyl)-5'-(methoxy stearate) oxazoline; (2) 2-stearyl-5-(hydroxymethyl)-5'-(methoxy stearate) oxazoline; and the like; (XVII) oxime compounds, such as (i) 2,3-butanedione monoxime (Aldrich 11,213-5);
(ii) acetone oxime (Aldrich A1,050-7); (iii) cyclohexanone oxime (Aldrich C10,220-2); (iv) 4-(trifluoromethoxy) benzamidoxime (Aldrich 42,223-1 ); (v) 2-nitrobenzaldoxime (Aldrich 24,204-7); (vi) 1-phenyl-1,2-propanedione 2-oxime (Aldrich 22,009-4); and the like; (XVIII) azoles, such as (a) pyrazole compounds, such as (1) pyrazole (Aldrich P5,660-7); (2) 1-nitro pyrazole (Aldrich 39,074-7); (3) 4-iodo pyrazole (Aldrich 21,399-3); (4) 4-bromo pyrazole (Aldrich 37,482-2); (5) 3,5-dimethyl pyrazole (Aldrich D18,200-1 );
(6) 4-bromo-3-methylpyrazole (Aldrich 27,823-8); (7) 4-bromo-3,5-dimethyl pyrazole (Aldrich B6,440-7); (8) 3-amino-5-phenyl pyrazole (Aldrich 39,379-7); (9) ethyl 4-pyrazolecarboxylate (Aldrich 30,078-0); (10) 1,1'-cyclopentylidene bis-1-H-pyrazole (Aldrich 39,415-7); (11) a-((2-ethoxy-2-oxoethoxy)imino)-3-pyrazoleacetic acid (Aldrich 38,971-4); (12) ethyl 5-amino-1-phenyl-4-pyrazole carboxylate (Aldrich 37,944-1); (13) 1,1'-(1-ethylpropylidene)bis-1-H-pyrazole (Aldrich 39,414-9); (14) ethyl 3-amino-4-pyrazolecarboxylate (Aldrich A4,500-9); (15) 3,5-bis(trifluoromethyl) pyrazole (Aldrich 39,039-9); (16) N-(tert-butoxycarbonyl)-1H-pyrazole-1-carbox amidine (Aldrich 44,201-1); (17) 3,5-dimethylpyrazole-1-carboxamide (Aldrich D18,220-6); (18) 3,5-dimethylpyrazole-1-methanol (Aldrich 33,145-7); (19) 2,3-dimethyl-1-phenyl-3-pyrazolin-5-one, (Aldrich A9,135-3); (b) imidazole compounds such as (1 ) imidazole (Aldrich 43,615-1 ); (2) 4-methyl imidazole (Aldrich 19,988-5); (3) 2-ethyl imidazole (Aldrich 23,934-8); (4) 2-ethyl-4-methylimidazole (Aldrich E3,665-2); (5) 2-propyl imidazole (Aldrich 37,537-3); (6) 2-isopropyl imidazole (Aldrich 37,399-0); (7) 1-acetylimidazole (Aldrich 15,786-41); (8) 1-benzylimidazole (Aldrich 11,641-6); (9) 2-undecyl imidazole (Aldrich 40,948-0); (10) 1,5-dicyclohexyl imidazole (Aldrich 31,654-7); (11) 1-(2,4,6-triisopropyl benzene sulfonyl imidazole (Aldrich 40,948-0); (12) 1-(mesitylene sulfonyl) imidazole (Aldrich 24,422-8); (13) 1-trans-cinnamoyl imidazole (Aldrich 21,904-5); (14) 2-methyl-4-nitro-1-imidazole propionitrile (15) 1,1'-carbonyl diimidazole (Aldrich 11,553-3);
(16) 1,1'-thiocarbonyl diimidazole (Aldrich 15,605-1); (17) 1,1'-sulfonyl diimidazole (Aldrich 36,781-8); (18) 1,1'-oxalyldiimidazole (Aldrich 36,643-9); Aldrich 37,769-4); (19) 5-methyl benzimidazole (Aldrich 30,523-5); (c) triazole derivatives such as (1) 1,2,4-triazole (Aldrich T4,610-8); (2) 4-amino-1,2,4-triazole (Aldrich A8,180-3); (3) benzotriazole (Aldrich B1,140-0); (4) 1H-benzotriazole carboxaldehyde (Aldrich 44,691-2); (5) benzotriazole-5-carboxylic acid (Aldrich 30,423-9); (6) 1-(methoxy methyl)-1 H-benzotriazole (Aldrich 43,802-0); (7) 5-methyl-1 H-benzotriazole (Aldrich 19,630-4); (8) N-(triphenylphosphoranylidene)-1H-benzotriazole-1-methane amine (Aldrich 44,693-9); (9) 1-aminobenzotriazole (Aldrich 38,637-5); (10) 1-cyanobenzotriazole (Aldrich 38,181-0); (11) (4-morpholinyl methyl) benzotriazole (Aldrich 46,750-2); (12) (4-morpholinyl phenylmethyl) benzotriazole (Aldrich 46,926-2); (13) (1-(4-morpholinyl) propyl) benzotriazole (Aldrich 47,108-9); (d) those with four nitrogens in the cyclic ring such as (1) 5-mercapto-1-methyltetrazole (Aldrich 35,787-1); (2) 1,5-pentamethylene tetrazole (Aldrich P,720-7); (XIX) bisamides, including those of the structure RCONH-R'-NHOCR, where R is an alkyl of from about 2 to about 30 carbon atoms or aryl, R' is an alkylene with from about 2 to about 30 carbon atoms, as disclosed in U.S. Patent 5,667,568, wherein examples of bisamides include (a) N,N'-ethylene bis-stearamide; (b) N,N'-propylene bis-stearamide; (c) N,N'-butylene bis-stearamide; (d) N,N'-hexylene bis-stearamide; (e) N,N'-heptylene bis-stearamide; (f) N,N'-octylene bis-stearamide; (g) N,N'-decylene bis-stearamide; (h) N,N'-dodecylene bis-stearamide; (i) N,N'-stearylene bis-stearamide; (j) N,N'-ethylene bis-lauramide; (k) N,N'-propylene bis-lauramide; (l) butylene bis-lauramide; (m) N,N'-hexylene bis-lauramide; (n) N,N'-heptylene bis-lauramide; (o) N,N'-octylene bis-lauramide; (p) N,N'-decylene bis-lauramide;
(q) N,N'-dodecylene bis-lauramide; (r) N,N'-stearylene bis-lauramide, with preferred bisamides include N,N'-stearylene bis-stearamide, N,N'-stearylene bis-lauramide; (XX) organic acid salts, such as (1 ) diethyldithiocarbamic acid ammonium salt (Aldrich 35,954-8); (2) diethyldithiocarbamic acid diethylammonium salt (Aldrich 31,811-6); (3) L-alanine ethyl ester hydrochloride (Aldrich 85,566-9); (4) D,L-alanine ethyl ester hydrochloride (Aldrich 26,886-0); (5) ethyl 4-aminobutyrate hydrochloride (Aldrich 39,066-6); (6) 2-ethyl-2-thiopseudourea hydrobromide (Aldrich 30,131-0); (7) formamidine hydrochloride (Aldrich 26,860-7); (8) N-methylhydroxylamine hydrochloride (Aldrich M5,040-0), and the like, as well as mixtures thereof.
Any desired or effective colorant can be employed in the inks of the present invention, including dyes, pigments, mixtures thereof, and the like, provided that the colorant can be dissolved or dispersed in the ink vehicle, with solvent or alcohol (spirit) soluble dyes being preferred.
Particularly preferred dyes include the Macrolex series available from Bayer and the Ceres dyes, such as Ceres Blue N, the Savinyl series available from Clariant, such as Savinyl Yellow RLS, Red 3BL, Blue GLS, Black RLSN, Black NS, and Duasyn Black A-RG VP280; the Orasol dyes available from Ciba Geigy, such as Orasol Yellow 4GN, Yellow 2GLN, Yellow 3R, Orange G, Orange RG, Red 3GL, Red 2B, Red BL, Pink 5BLG, Blue GN, Blue BL, Black CN, Black RL, and Black RL1; the Neopen Series available from BASF, such as Neopen Yellow 075, yellow 159, orange 252, red 336, red 335, red 366, blue 808 or 807, black X53, and Black X55. Also suitable are dispersed dyes and polymeric dyes, such as the Millijet Series available from Milliken.
Examples of suitable pigments include Violet Toner VT-8015 (Paul Uhlich); Paliogen Violet 5100 (BASF); Paliogen Violet 5890 (BASF);
Permanent Violet VT 2645 (Paul Uhlich); Heliogen Green L8730 (BASF); Argyle Green XP-111-S (Paul Uhlich); Brilliant Green Toner GR 0991 (Paul Uhlich);
Lithol Scarlet D3700 (BASF); Toluidine Red (Aldrich); Scarlet for Thermoplast NSD PS PA (Ugine Kuhlmann of Canada); E.D. Toluidine Red (Aldrich); Lithol Rubine Toner (Paul Uhlich); Lithol Scarlet 4440 (BASF); Bon Red C (Dominion ~

Color Company); Royal Brilliant Red RD-8192 (Paul Uhlich); Oracet Pink RF
(Ciba-Geigy); Paliogen Red 3871 K (BASF); Paliogen Red 3340 (BASF); Lithol Fast Scarlet L4300 (BASF); Heliogen Blue L6900, L7020 (BASF); Heliogen Blue K6902, K6910 (BASF); Heliogen Blue D6840, D7080 (BASF); Sudan Blue OS
(BASF); Neopen Blue FF4012 (BASF); PV Fast Blue B2G01 (American Hoechst);
Irgalite Blue BCA (Ciba-Geigy); Paliogen Blue 6470 (BASF); Sudan III (Red Orange) (Matheson, Colemen Bell); Sudan II (Orange) (Matheson, Colemen Bell); Sudan Orange G (Aldrich), Sudan Orange 220 (BASF); Paliogen Orange 3040 (BASF); Ortho Orange OR 2673 (Paul Uhlich); Paliogen Yetlow 152, 1560 (BASF); Lithol Fast Yellow 0991 K (BASF); Paliotol Yellow 1840 (BASF);
Novoperm Yellow FGL (Hoechst); Permanent Yellow YE 0305 (Paul Uhlich);
Lumogen Yellow D0790 (BASF); Suco-Yellow L1250 (BASF); Suco-Yellow D1355 (BASF); Suco Fast Yellow D1355, D1351 (BASF); Hostaperm Pink E (American Hoechst); Fanal Pink D4830 (BASF); Cinquasia Magenta (Du Pont); Paliogen Black L0084 (BASF); Pigment Black K801 (BASF); and carbon blacks such as REGAL 330~ (Cabot), Carbon Black 5250, Carbon Black 5750 (Columbia Chemical), and the like. Additional examples of suitable spirit solvent dyes include Neozapon Red 492 (BASF); Orasol Red G (Ciba Geigy); Direct Brilliant Pink B (Crompton F~ Knowles); Aizen Spilon Red C-BH (Hodogaya Chemical);
Kayanol Red 3BL (Nippon Kayaku); Levanol Brilliant Red 3BW (Mobay Chemical); Levaderm Lemon Yellow (Mobay Chemical); Spirit Fast Yellow 3G;
Aizen Spilon Yellow C-GNH (Hodogaya Chemical); Sirius Supra Yellow GD 167;
Cartasol Brilliant Yellow 4GF (Sandoz); Pergasol Yellow CGP (Ciba Geigy);
Orasol Black RLP (Ciba Geigy); Savinyl Black RLS (Sandoz); Dermacarbon 2GT
(Sandoz); Pyrazol Black BG (ICI); Morfast Black Conc. A (Morton-Thiokol);
Diaazol Black RN Quad (ICI); Orasol Blue GN (Ciba-Geigy); Savinyl Blue GLS
(Sandoz); Luxol Blue MBSN (Morton-Thiokol); Sevron Blue 5GMF (ICI); Basacid Blue 750 (BASF), and the like. Neozapon Black X51 (C.I. Solvent Black, C.I.
12195) (BASF), Sudan Blue 670 (C.I. 61554) (BASF), Sudan Yellow 146 (C.I.
12700) (BASF), and Sudan Red 462 (C.I. 26050) (BASF) are preferred.
The colorant is present in the ink in any desired or effective amount to obtain the desired color and hue, typically at least about 0.5 percent by weight of the ink, preferably at least about 1 percent by weight, and more preferably at least about 2 percent by weight of the ink, and typically no more than about 10 percent by weight of the ink, preferably no more than about 7 percent by weight of the ink, and more preferably no more than about 6 percent by weight of the ink, although the amount can be outside of these ranges.
The inks of the present invention also contain both a cationic and an anionic surfactant. While not being limited to any particular theory, it is believed that at the temperatures at which the ink is jetted from the printhead (typically at least about 125 and typically no more than about 170°C, although the temperature can be outside of this range), the cationic and anionic surfactants are partly or fully thermally dissociated. When the ink cools to ambient temperature (typically from about 20 to about 25°C), however, the cationic and anionic surfactants can become strongly associated by Coulomb attractions. This strong association is believed to form a hard shell at the surface of the ink drop, thereby producing images that are smear resistant and possibly also with increased surface hardness.
Although some of the surfactant molecules are dissolved in the bulk of the ink, the ink bulk viscosity is not undesirably affected because the overall concentration of surfactant in the ink is usually relatively small. The addition of the optional neutral surfactant provides a method of controlling ~
~ CA 02341113 2001-03-16 the amount of association by diluting the surface concentration of the charged surfactants.
Any anionic surfactant can be employed. Examples of suitable anionic surfactants include alkyl carboxylic acids of the general formula RCOOH, wherein R is an alkyl group, typically with at least about 5 carbon atoms, and typically with no more than about 20 carbon atoms, although the number of carbon atoms can be outside of these ranges, including those of the formula CH3(CH2)XCOOH wherein x is an integer representing the number of repeat -CH2- units, typically being at least about 5, and preferably at least about 10, and typically being no more than about 20, and preferably no more than about 18, although the value of x can be outside of these ranges. Salts of these acids can also be used. Specific examples of anionic surfactants of this formula include palmitic acid, wherein x=14, lauric acid, wherein x=10, stearic acid, wherein x=16, and the like. Branched, unsaturated, and cyclic acids can also be used in addition to linear acids.
Also suitable are alkyl dicarboxylic acids of the general formula HOOC-R-COOH, wherein R is an alkyl group, typically with at least about 10 carbon atoms and typically with no more than about 20 carbon atoms, although the number of carbon atoms can be outside of these ranges, including those of the formula HOOC(CH2)xC00H wherein x is an integer representing the number of repeat -CHZ- units, typically being at least about 10, preferably at least about 12, and more preferably at least about 16, and typically being no more than about 20, although the value of x can be outside of these ranges. Branched, unsaturated, and cyclic acids can also be used in addition to linear acids. Specific examples of anionic surfactants of this formula include undecanedioic acid and the like. Also suitable are alkyl sulfates, salts of sulfonated naphthalene-formaldehyde condensates, ~
~ CA 02341113 2001-03-16 salts of lignosulfonate, poly(methyl vinyl ether/maleic anhydride) salts, and those of the formula ROS03-B+ wherein R is an alkyl group, typically with at least about 5 carbon atoms, preferably with at least about 10 carbon atoms, and more preferably with at least about 16 carbon atoms, and typically with no more than about 20 carbon atoms, although the number of carbon atoms can be outside of these ranges, and B is a cation. Any desired or suitable cation can be employed, including monovalent, bivalent, trivalent, and polyvalent cations. Examples of suitable cations include, but are not limited to, alkali metal cations, such as Li+, Na+, and K+, alkaline earth metal cations, such as Mg2+ and Caz+, ammonium and quaternary amine cations such as NH4+, N(CH3)4+, and the like, as well as mixtures thereof.
Specific examples of anionic surfactants of this formula include sodium lauryl sulfate and the like. Also suitable are alkyl ether sulfates, of the formula R(OCH2CH2)nOS03-B+ wherein n is an integer with an average value of from about 1 to about 4, R is an alkyl group, typically with at least about 12 carbon atoms and typically with no more than about 15 carbon atoms, although the number of carbon atoms can be outside of this range, and B is a cation as defined above for the formula ROS03-B+. Specific examples of anionic surfactants of this formula include sodium lauryl ether sulfate (also known as sodium laureth sulfate) and the like. The anionic surfactant is present in the ink in any desired or effective amount, typically at least about 0.01 percent by weight of the ink, preferably at least about 0.1 percent by weight of the ink, and more preferably at least about 1 percent by weight of the ink, and typically no more than about 50 percent by weight of the ink, preferably no more than about 40 percent by weight of the ink, and more preferably no more than about 20 percent by weight of the ink, although the amount can be outside of these ranges.

Any cationic surfactant can be employed. Examples of suitable cationic surfactants include those of the general formula N(R~)X(R2)y(R3)Z+A-wherein R~ and R2 each, independently of the other, are hydrogen atoms, alkyl groups, typically with at least about 1 carbon atom, and typically with no more than about 25 carbon atoms, preferably with no more than about 20 carbon atoms, and more preferably with no more than about 18 carbon atoms, although the number of carbon atoms can be outside of these ranges, or a mixture thereof, R3 is an alkyl group, typically with at least about 1 carbon atom, and preferably with at least about 10 carbon atoms, and typically with no more than about 25 carbon atoms, and preferably with no more than about 18 carbon atoms, although the number of carbon atoms can be outside of these ranges, an aryl group, typically with at least about 5 carbon atoms, and preferably with at least about 6 carbon atoms, and typically with no more than about 25 carbon atoms, preferably with no more than about 20 carbon atoms, and more preferably with no more than about 18 carbon atoms, although the number of carbon atoms can be outside of these ranges, an alkylaryl group or arylalkyl group, typically with at least about 6 carbon atoms, and preferably with at least about 7 carbon atoms, and typically with no more than about 30 carbon atoms, preferably with no more than about 25 carbon atoms, and more preferably with no more than about 22 carbon atoms, although the number of carbon atoms can be outside of these ranges, or a mixture thereof, x, y, and z are integers representing the number of R~, R2, and R3 groups, wherein x is at least one and z is at least one and the sum of x+y+z=4, and A is an anion. Any desired or suitable anion can be employed, including monovalent, bivalent, trivalent, and polyvalent anions. Examples of suitable anions include, but are not limited to, Cl-, Br-, I-, HS04-, HS03-, 5042-, 5032-, CH2S03-, CH3S03-, CH3C6H4SO3 , N03 , HC00 , CFi3C00 , IiC03 , CO32~, HZP04 , HP042 , P043 , SCN
, BF4-, C104~, SS03-, or the like, as well as mixtures thereof. Specific examples of cationic surfactants of this formula include benzyl cetyl dimethyl ammonium chloride, wherein R~ is methyl, x is 2, R2 is benzyl, y is 1, R3 is cetyl dimethyl (-(CH2)~5(CH3)2), z is 1, and A is chloride, hexadecyl trimethyl ammonium bromide, wherein R~ is methyl, x is 3, RZ is hexadecyl, y is 1, and A is bromide, tetraheptyl ammonium bromide, wherein R~ is heptyl, x is 3, R3 is heptyl, z is 1, and A is bromide, and the like. Also suitable are octadecylamine, acetic acid salts of n-alkyl amines wherein the alkyl groups typically have at least about 1 carbon atom and typically have no more than about 25 carbon atoms, although the number of carbon atoms can be outside of this range, stearamido amine, stearamido morpholine, palmitic amidoalkyl dimethyl amine, stearic amido alkyl dimethyl amine, substituted imidazoline from oleic acid, alkyl dimethyl benzyl ammonium saccharinate, dihydydrogenated tallow dimethyl ammonium chloride, dialuryl dimethyl ammonium bromide, n-octyl decylamine, and the tike, as well as mixtures thereof. The cationic surfactant is present in the ink in any desired or effective amount, typically at least about 0.1 percent by weight of the ink, preferably at least about 0.5 percent by weight of the ink and more preferably at least about 1 percent by weight of the ink, and typically no more than about 50 percent by weight of the ink, preferably no more than about 40 percent by weight of the ink, and more preferably no more than about 20 percent by weight of the ink, although the amount can be outside of these ranges.
One particularly preferred pair of anionic and cationic surfactants is that of stearic acid and octadecylamine.

Any nonionic surfactant can be employed as the optional nonionic surfactant. Preferably, the nonionic surfactant has a melting point of at least about 70°C, and more preferably of at least about 100°C, with no necessary upper limit, although the melting point can be outside of these ranges. Examples of suitable nonionic surfactants include ethoxylated lanolin alcohol (typically having at least about 5 ethylene oxide repeat units and typically having no more than about 75 ethylene oxide repeat units), polyethylene glycol monostearate (typically having at least about 200 repeat ethylene glycol units and typically having no more than about 1,500 repeat ethylene glycol units), and the like, as well as mixtures thereof. The optional nonionic surfactant, when present, is present in the ink in any desired or effective amount, typically at least about 0.1 percent by weight of the ink, and preferably at least about 1 percent by weight of the ink, and typically no more than about 20 percent by weight of the ink, preferably no more than about 10 percent by weight of the ink, and more preferably no more than about 5 percent by weight of the ink, although the amount can be outside of these ranges.
The inks of the present invention further optionally contain a conductivity enhancing agent when conductive inks are desirable, as in applications such as electric field assisted hot melt acoustic ink printing processes. Any desired or effective conductivity enhancing agent can be employed. Specific examples of suitable conductivity enhancing agents include complexes of dianilines, including dianiline and bis dianiline compounds, such as (1 ) 2,2'-dithio dianiline (Aldrich 16,676-6), (2) 4,4'-dithiodianiline (Aldrich 36,946-26), (3) 3,3'-methylene dianiline (Aldrich 37,826-7), (4) 4,4'-methylene dianiline (Aldrich 13,245-4), (5) N-methyl-4,4'-methylene dianiline (Aldrich 42,282-7), (6) 4,4'-methylene bis(2,6-diethyl aniline) (Aldrich 36,078-3), (7) 4,4'-methylene bis(2,6-diisopropyl-N,N-dimethylaniline) (Aldrich 40,353-9), (8) 4,4'-methylene bis (N,N-dimethylaniline) (Aldrich M4,445-1 ), (9) 4,4'-methylene bis (2,6-dimethylaniline) (Aldrich 36,079-1 ), (10) 4,4'-methylene bis (3-chloro-2,6-diethylaniline) (Aldrich 42,660-1), (11) 3,3'-(sulfonyl bis(4,1-phenylene))dianiline (Aldrich 44,095-7), (12) 4,4'-(1,3-phenylene diisopropylidene) bisaniline (Aldrich 45,048-0), and the like, as well as mixtures thereof, said dianilines being complexed with, for example, conductivity inducing phosphorous compounds such as phosphorus-containing acid compounds, with specific examples including (1 ) phenylphosphinic acid (Aldrich P2,880-8), (2) dimethylphosphinic acid (Aldrich 32,829-4), (3) methyl phosphonic acid (Aldrich 28,986-8), and the like, as well as mixtures thereof.
Additional suitable conductivity enhancing agents include (1 ) (diethyl-(4-aminobenzyl) phosphonate (Aldrich 33,847-8), (2) diethyl-(phthalimidomethyl) phosphonate (Aldrich 36,622-6), (3) diethyl-(2,2,2-trifluoro-1-hydroxyethyl) phosphonate (Aldrich 43,982-7), (4) Biphenyl succinimidyl phosphate (Aldrich 45,061-8), (5) dihexadecyl phosphate (Aldrich 27,149-7), (6) undecylenic acid zinc salt (hardness value 68; Aldrich 32,958-4), (7) zinc bis(2,2,6,6-tetramethyl-3,5-heptanedionate) (Aldrich 41,773-4), (8) zinc cyclohexanebutyrate (Aldrich 22,841-9), (9) zinc stearate (Aldrich 30,756-4), (10) methyl-1-adamantane sulfonate (Aldrich 40,956-1 ), (11 ) octadecyl-4-chlorobenzene sulfonate (Aldrich 47,799-0), (12) tetrabutylammonium trifluoromethanesulfonate (Aldrich 34,509-1), (13) S,S'-ethylene-p-toluene thiosulfonate (Aldrich 23,257-2), (14) pyridinium-3-nitrobenzene sulfonate (Aldrich#27,198-5), (15) p-toluene sulfonyl chloride (Aldrich 24,087-7), (16) o-toluene sulfonyl chloride (Aldrich 15,971-9), (17) 1-(p-toluene sulfonyl) imidazole (Aldrich 24,424-4), (18) 1-(p-toluene sulfonyl)-3-vitro-1,2,4-triazole (Aldrich 24,417-1), (19) 2,4,6-triisopropyl benzene sulfonyl chloride (Aldrich 11,949-0), (20) 1-(2,4,6-triisopropyl benzene sulfonyl) imidazole (Aldrich 40,948-0), (21) 1-(2,4,6-triisopropyl benzene sulfonyl)-3-vitro-1,2,4-triazole (Aldrich 40,948-0), (22) 4-nitrobenzene sulfonyl chloride (Aldrich 27,224-8), and the like, as well as mixtures thereof. The conductivity enhancing agent, when present, is present in the ink in any desired or effective amount, typically at least about 1 percent by weight of the ink, and typically no more than about 20 percent by weight of the ink, preferably no more than about 10 percent by weight of the ink, and more preferably no more than about 5 percent by weight of the ink, although the amount can be outside of these ranges.
The inks of the present invention further optionally contain an antioxidant. The optional antioxidants of the ink compositions protect the images from oxidation and also protect the ink components from oxidation during the heating portion of the ink preparation process. Specific examples of suitable antioxidants include (but are not limited to) (1 ) 2,6-di-tert-butyl-4-methoxyphenol (Aldrich 25,106-2), (2) 2,4-di-tert-butyl-6-(4-methoxybenzyl) phenol (Aldrich 23,008-1), (3) 4-bromo-2,6-dimethylphenol (Aldrich 34,951-8), (4) 4-bromo-3,5-didimethylphenol (Aldrich B6,420-2), (5) 4-bromo-2-nitrophenol (Aldrich 30,987-7), (6) 4-(diethyl aminomethyl)-2,5-dimethylphenol (Aldrich 14,668-4), (7) 3-dimethylaminophenol (Aldrich D14,400-2), (8) 2-amino-4-tert-amylphenol (Aldrich 41,258-9), (9) 2,6-bis(hydroxymethyl)-p-cresol (Aldrich 22,752-8), (10) 2,2'-methylenediphenol (Aldrich B4,680-8), (11) 5-diethylamino)-2-nitrosophenol (Aldrich 26,951-4), (12) antimony dialkyl phosphorodithioate (commercially available from Vanderbilt), (13) molybdenum oxysulfide dithiocarbamate (commercially available from Vanderbilt), (14) (nickel-bis(o-ethyl(3,5-di-tert-butyl-4-hydroxybenzyl) phosphonate (commercially available from Ciba Geigy), (15) 4,4'-methylene-bis(dibutyldithiocarbamate) (commercially available as Vanlube 7723 from Vanderbilt), (16) tetrasodium-N-(1,2-dicarboxyethyl)-N-octadecyl sulfosuccinamate (commercially available from American Cyanamid), (17) 2,6-di-tert-butyl-a-dimethylamino-4-cresol (commercially available as Ethanox-703 from Ethyl Corporation), (18) 2,2'-isobutylidene-bis(4,6-dimethyl phenol) (commercially available as Vulkanox NKF from Mobay Chemicals), (19) 2,2'-methylenebis(6-tert-butyl-4-methylphenol) (commercially available as Cyanox-2246, Aldrich 41,315-5), (20) 2,2'-methylenebis(6-tert-butyl-4-ethylphenol) (commercially available as Cyanox-425, Atdrich 41,314-3), (21) N-isopropyl-N'-phenyl-phenylene diamine (commercially available as Santoflex-IP from Monsanto Chemicals, (22) N-(1,3-dimethylbutyl)-N'-phenyl-phenylene-diamine (commercially available as Santoflex-13 from Monsanto Chemicals), (23) N,N'-di(2-octyl)-4-phenylene diamine (commercially available as Antozite-1 from Vanderbilt), (24) N,N'-bis(1,4-dimethylpentyl)-4-phenylene diamine (commercially available as Santoflex-77 from Monsanto Chemicals), (25) 2,4,6-tris-(N-1,4-dimethyl pentyl-4-phenylenediamino)-1,3,5-triazine (commercially available as Durazone-37 from Uniroyal), (26) D-raffinose pentahydrate (Aldrich 20,667-9), (27) 2,2'-methylene bis(6-tert-butyl-4-methyl-phenol) (Aldrich 41,313-5), (28) 2,6-di-tert-butyl-4-(dimethylaminomethyl) phenol (Aldrich 41,327-5), (29) 4-dodecylresorcinol (Aldrich D22,260-7), and the like, as well as mixtures thereof. When present, the optional antioxidants are present in any desired or effective amount, typically at least about 0.01 percent by weight of the ink, preferably at least about 0.05 percent by weight of the ink, and more preferably at least about 0.1 percent by weight of the ink, and typically no more than about 2 percent by weight of the ink, and preferably no more than about 0.5 percent by weight of the ink, although the amount can be outside of these ranges.
The inks of the present invention further optionally contain a UV absorber. The optional UV absorbers in the inks of the present invention primarily protect the images generated therewith from UV degradation.
Specific examples of suitable UV absorbers include (but are not limited to) (1 ) 2-amino-2',5-dichlorobenzophenone (Aldrich 10,515-5), (2) 2'amino-4',5'-dimethoxyacetophenone (Aldrich 32,922-3), (3) 2-benzyl-2-(dimethylamino)-4'-morpholino butyrophenone (Aldrich 40,564-7), (4) 4'-benzyloxy-2'-hydroxy-3'-methylacetophenone (Aldrich 29,884-0), (5) 4,4'-bis(diethylamino) benzophenone (Aldrich 16,032-6), (6) 5-chloro-2-hydroxy benzophenone (Aldrich C4,470-2), (7) 4'-piperazinoacetophenone (Aldrich 13,646-8), (8) 4'-piperidinoacetophenone (Aldrich 11,972-5), (9) 2-amino-5-chlorobenzophenone (Aldrich A4,556-4), (10) 2-bromo-2',4-dimethoxyacetophenone (Aldrich 19,948-6), (11) 2-bromo-2',5'-dimethoxyacetophenone (Aldrich 10,458-2), (12) 2-bromo-3'-nitroacetophenone (Aldrich 34,421-4), (13) 2-bromo-4'-nitroacetophenone (Aldrich 24,561-5), (14) 3',5'-diacetoxyacetophenone (Aldrich 11,738-2, (15) 2-phenylsulfonyl) acetophenone (Aldrich 34,150-3), (16) 3'-aminoacetophenone (Aldrich 13,935-1 ), (17) 4'-aminoacetophenone (Aldrich A3,800-2), (18) 1 H-benzotriazole-1-acetonitrile (Aldrich 46,752-9), (19) 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (Aldrich 42,274-6), (20) 1,1-(1,2-ethane-diyl)bis(3,3,5,5-tetramethylpiperazinone) (commercially available from Goodrich Chemicals), (21 ) 2,2,4-trimethyl-1,2-hydroquinoline (commercially available from Mobay Chemical), (22) 2-(4-benzoyl-3-hydroxy phenoxy)ethylacrylate, (23) 2-dodecyl-N-(1,2,2,6,6-pentamethyl-4-piperidinyl) succinimide (commercially available from Aldrich Chemical Co., ~

Milwaukee, WI), (24) 2,2,6,6-tetramethyl-4-piperidinyl/~,~,~',~3'-tetramethyl-3,9-(2,4,8,10-tetraoxo spiro(5,5)-undecane) diethyl)-1,2,3,4-butane tetracarboxylate (commercially available from Fairmount), (25) N-p-ethoxycarbonylphenyl)-N'-ethyl-N'-phenylformadine (commercially available from Givaudan), (26) 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline (commercially available from Monsanto Chemicals), (27) 2,4,6-tris-(N-1,4-dimethylpentyl-4-phenylenediamino)-1,3,5-triazine (commercially available from Uniroyal), (28) 2-dodecyl-N-(2,2,6,6-tetramethyl-4-piperidinyl) succinimide (commercially available from Aldrich Chemical Co.), (29) N-(1-acetyl-2,2,6,6-tetramethyl-4-piperidinyl)-2-dodecyl succinimide (commercially available from Aldrich Chemical Co.), (30) (1,2,2,6,6-pentamethyl-4-piperidinyl/ ~, ~~', ~'-tetramethyl-3,9-(2,4,8,10-tetraoxo-spiro-(5,5)undecane)diethyl)-1,2,3,4-butane tetracarboxylate (commercially available from Fairmount), (31 ) (2,2,6,6-tetramethyl-4-piperidinyl)-1,2,3,4-butane tetracarboxylate (commercially available from Fairmount), (32) nickel dibutyl dithio carbamate (commercially available as UV-Chek AM-105 from Ferro), and the like, as well as mixtures thereof. The optional UV absorber, when present, is present in the ink in any desired or effective amount, typically at least about 0.01 percent by weight of the ink, preferably at least about 0.05 percent by weight of the ink, and more preferably at least about 0.1 percent by weight of the ink, and typically no more than about 2 percent by weight of the ink, and preferably no more than about 0.5 percent by weight of the ink, although the amount can be outside of these ranges.
Other optional additives to the inks include clarifiers, such as UNION CAMP~ X37-523-235 and UNION CAMPO UC-235 (commercially available from Union Camp), in an amount typically of at least about 5 percent by weight of the ink, and preferably at least about 10 percent by weight of the ink, and typically no more than about 40 percent by weight of the ink, and preferably no more than about 25 percent by weight of the ink, although the amount can be outside of this range, tackifiers, such as FORAL~ 85, a glycerol ester of hydrogenated abietic (rosin) acid (commercially available from Hercules), FORALO 105, a pentaerythritol ester of hydroabietic (rosin) acid (commercially available from Hercules), CELLOLYNO 21, a hydroabietic (rosin) alcohol ester of phthalic acid (commercially available from Hercules), ARAKAWA KE-311 Resin, a triglyceride of hydrogenated abietic (rosin) acid (commercially available from Arakawa Chemical Industries, Ltd.), synthetic polyterpene resins such as NEVTACO 2300 and NEVTAC~ 80 (commercially available from Neville Chemical Company), WINGTACKO 86, a modified synthetic polyterpene resin (commercially available from Goodyear), and the like, in an amount typically of at least about 1 percent by weight of the ink, and preferably at least about 3 percent by weight of the ink, and typically no more than about 40 percent by weight of the ink, preferably no more than about 20 percent by weight of the ink, and more preferably no more than about 10 percent by weight of the ink, although the amount can be outside of this range, adhesives, such as VERSAMIDO 757, 759, 744, and 963 (commercially available from Henkel), in an amount typically of at least about 0.5 percent by weight of the ink, preferably at least about 5 percent by weight of the ink, and more preferably at least about 10 percent by weight of the ink, and typically no more than about 50 percent by weight of the ink, preferably no more than about 40 percent by weight of the ink, and more preferably no more than about 20 percent by weight of the ink, although the amount can be outside of this range, plasticizers, such as UNIPLEXO 250 (commercially available from Uniplex), the phthalate ester plasticizers commercially available from Monsanto under the trade name SANTICIZERO, such as dioctyl phthalate, diundecyl phthalate, alkylbenzyl phthalate (SANTICIZERO 278), KP-1400, a triphenyl phosphate (commercially available from MC
Corporation), MORFLEXO 150, a dicyclohexyl phthalate (commercially available from Morflex Chemical Company, Inc.), trioctyl trimellitate (commercially available from Eastman Kodak Co.), and the like, in an amount typically of at least about 0.5 and typically no more than about 20 percent by weight of the ink, and preferably no more than about 10 percent by weight of the ink, although the amount can be outside of this range, and the like.
The ink compositions of the present invention typically have melting points no tower than about 60°C, preferably no lower than about 70 ° C, and more preferably no lower than about 80 ° C, and typically have melting points no higher than about 160°C, preferably no higher than about 140°C, and more preferably no higher than about 120°C, although the melting point can be outside of these ranges.
The ink compositions of the present invention generally have melt viscosities at the jetting temperature (typically no lower than about 75 ° C, preferably no lower than about 100 ° C, and more preferably no lower than about 120°C, and typically no higher than about 180°C, preferably no higher than about 150°C, and more preferably no higher than about 130°C, although the jetting temperature can be outside of these ranges) typically of no more than about 25 centipoise, preferably no more than about 20 centipoise, and even more preferably no more than about 10 centipoise, and typically of no less than about 2 centipoise, preferably no less than about 5 centipoise, and even more preferably no less than about 7 centipoise, although the melt viscosity can be outside of these ranges. Since image hardness tend to drop with lower viscosities, it is preferred that the viscosity be as low as possible while still retaining the desired degree of image hardness.
Hardness is a property of solids and plastics that is defined by their solidity and firmness as measured by their resistance to indentation by an indenter of fixed shape and size under a static load. The hardness of images can be measured with a Digital-Pencil style Durometer, Model 211 B-00 PTC, obtained from Pacific Transducer Corporation, using ASTM Standard specifications D2240 for resistance to penetration with a conical (30 degrees included angle) indenter and applying a 1 kilogram load. The hardness range for materials as measured with this instrument is from about 1 to about 100, the latter being the highest measurable value. It is believed that the images generated with the inks of the present invention, after cooling to ambient temperature (typically from about 20 to about 25°C, although ambient temperature can be outside of this range) will exhibit hardness values of at least about 60 or more, with no necessary upper limit (although practical upper limits may be around 90).
The inks of the present invention typically undergo, upon freezing on the print substrate, a change from a liquid state to a solid state in a period of less than about 100 milliseconds, preferably less than about 50 milliseconds, and more preferably less than about 10 milliseconds, although the time can be outside of these ranges. There is no necessary lower limit on this period of time for the inks; it is believed that practically achievable lower limits are around 5 milliseconds, although, if practically achievable, lower periods of time are acceptable.

The inks of the present invention typically exhibit acoustic-loss values of no more than about 100 decibels per millimeter, preferably no more than about 60 decibels per millimeter, and more preferably no more than about 40 decibels per millimeter, although the acoustic-loss value can be outside of these ranges. There is no necessary lower limit on acoustic-loss value for the inks; it is believed that practically achievable lower limits are around 10 decibels per millimeter, although, if practically achievable, lower acoustic-loss values are acceptable. Acoustic-loss can be measured by placing a sample of the material to be measured between two transducers with the temperature set at about 150°C. The samples are allowed to equilibrate at 150°C for five minutes. The two transducers are then brought together to maximize the acoustic signal. The amplitude and the position of the signals are recorded. The two transducers are then separated by a distance varying from about 25.4 microns to about 125.4 microns, recording each time the amplitude and the position of the signal. Preferably, each measurement is performed three times, and three samples of the same material are measured. The attenuation decibels per millimeter is then calculated by ratioing the amplitude values obtained at different separation distances.
The inks of the present invention typically exhibit a conductivity of no less than about 2 log(picomho/cm), preferably no less than about 6 log(picomho/cm), more preferably no less than about 6.5 log(picomho/cm), and even more preferably no less than about 7 log(picomho/cm), although the conductivity can be outside of these ranges.
While there is no upper limit on conductivity, typical conductivity values generally do not exceed about 9 log(picomho/cm). Conductivity can be measured under melt conditions (typically at about 150°C) by placing an aluminum electrode in the molten ink and reading the resistivity output on a GenRad 1689 precision RLC Digibridge at a frequency of 1 kiloHertz). The conductivity of the material is measured in terms of the reciprocal of resistivity, which is the capacity for electrical resistance.
The ink compositions of the present invention can be prepared by any desired or suitable method. For example, the ink ingredients can be mixed together, followed by heating, typically to a temperature of from about 100 to about 140°C, although the temperature can be outside of this range, and stirring until a homogeneous ink composition is obtained, followed by cooling the ink to ambient temperature (typically from about 20 to about 25°C). The inks of the present invention are solid at ambient temperature.
The present invention is also directed to a process which entails incorporating an ink of the present invention into an ink jet printing apparatus, melting the ink, and causing droplets of the melted ink to be ejected in an imagewise pattern onto a recording sheet. In one preferred embodiment, the printing apparatus employs an acoustic ink jet process, wherein droplets of the ink are caused to be ejected in imagewise pattern by acoustic beams. In a particularly preferred embodiment, the printing apparatus employs an acoustic ink jet printing process wherein droplets of the ink are formed by acoustic beams without imparting a substantial velocity component toward the print medium, using a droplet forming force that is sufficient only to form the ink droplets, and the printing process further comprises generating an electric field to exert an electrical force different from the droplet forming force on the ink droplets to move the ink droplets toward the print medium, and controlling the electrical force exerted on the formed complete ink droplets by the electric field.

Any suitable substrate or recording sheet can be employed, including plain papers such as Xerox~ 4024 papers, Xerox~ Image Series papers, Courtland 4024 DP paper, ruled notebook paper, bond paper, silica coated papers such as Sharp Company silica coated paper, JuJo paper, and the like, transparency materials, fabrics, textile products, plastics, polymeric films, inorganic substrates such as metals and wood, and the like.
In a preferred embodiment, the process entails printing onto a porous or ink absorbent substrate, such as plain paper.
Specific embodiments of the invention will now be described in detail. These examples are intended to be illustrative, and the invention is not limited to the materials, conditions, or process parameters set forth in these embodiments. All parts and percentages are by weight unless otherwise indicated.
SYNTHESIS I
Synthesis of C,$-C,6 Carbamate Vehicle A carbamate vehicle of the formula O
H3CCH2C)~ ~
I
H
was prepared as follows. In a 500 milliliter Erlenmeyer flask with a magnetic stirrer, 82 grams of 1-hexadecanol and 0.1 gram of 1,4-diazabicyclo(2.2.2)octane (catalyst) were mixed with 200 grams of toluene and the resultant mixture was heated to 80°C. To this heated solution, grams of octadecyl isocyanate was slowly added. The mixture was heated for 3 hours at 80°C, after which the mixture was allowed to cool to room temperature. The product precipitated out of solution, and was filtered and recrystallized from isopropyl alcohol to yield the white solid product with a melting point of 83°C.
SYNTHESIS II
Synthesis of C~$-C4 Urea Vehicle A urea vehicle of the formula O
H3CCH2C)pN~
I I
H H
was prepared as follows. In a 500 milliliter Erlenmeyer flask with a magnetic stirrer, 39 grams of n-butyl amine were mixed with 200 grams of toluene and the resultant mixture was heated to 80°C. To this heated solution, 150 grams of octadecyl isocyanate was slowly added. The mixture was heated for 3 hours at 80°C, after which the mixture was allowed to cool to room temperature. The product precipitated out of solution, and was filtered and recrystallized from isopropyl alcohol to yield the white solid product with a melting point of 98°C.
SYNTHESIS III
Synthesis of C~8-C$ Urea Vehicle A urea vehicle of the formula ' CA 02341113 2001-03-16 I
H3CCH2C)~ yN~yN
I I
H H
was prepared as follows. In a 500 milliliter Erlenmeyer flask with a magnetic stirrer, 36.7 gams of octyl amine were mixed with 200 grams of toluene and the resultant mixture was heated to 80°C. To this heated solution, 80 grams of octadecyl isocyanate was slowly added. The mixture was heated for 3 hours at 80°C, after which the mixture was allowed to cool to room temperature. The product precipitated out of solution, and was filtered and recrystallized from isopropyl alcohol to yield the white solid product with a melting point of 98°C.
SYNTHESIS IV
Synthesis of Stearylcarbamoyl Alkanoate Vehicles In a 100 milliliter round bottom flask fitted with a reflux condensor and nitrogen purge were placed 14.78 grams (0.05 mole) of octadecylisocyanate, 50 milliliters of toluene, and 10 milligrams of a catalyst 1,4-diazabicyclo(2.2.2)octane. Stearyl alcohol (13.53 grams; 0.05 mole) was then rapidly added and the mixture heated to reflux.
Precipitation was evident at completion of the alcohol addition. The reaction mixture was heated at reflux for 5 hours, cooled, and filtered to secure stearylcarbamoyl stearate as a white solid melting at 85°C in 85 percent yield. Other stearylcarbamates were prepared in an analogous fashion by varying the alcohol component of the reaction mixture as shown:
Carbamate Alcohol mp (°C) Stearylcarbamoyl octoate 1-octanol 66 ' CA 02341113 2001-03-16 Stearylcarbamoyl dodecanoate 1-dodecanol 72 Stearylcarbamoyl hexadecanoate1-hexadecanol 83 INK SAMPLE PREPARATION AND TESTING
All ink samples were prepared by adding to an aluminum dish the most viscous compounds first, followed by the less viscous ones (other than the dye). The aluminum dish was then placed on a hot plate set at 130°C. The sample was covered by a glass slice and heated for about an hour to melt all of the components. A magnetic stirrer was used at the end of this cycle to mix the melted sample. A weight was used to keep the dish stable. The appropriate amount of dye was then added to the sample. The covered sample was stirred for 1.5 hour and then poured into a brass mold.
The sample was left to stand overnight before evaluation was done.
HARDNESS TEST
A PTC Durometer stand Model 476 211 B-00 was used to determine the hardness of the samples.
SMEAR TEST
A draw-down of each of the samples was made on XeroxO
Color Xpressions0 paper using a #5 rod (Consler Scientific Design, Inc.) to obtain a coated film about 12 microns thick. The smear was determined 18 to 24 hours later as follows: The coating was rubbed with a Pink PearlO 100 eraser (Dixon) for 1 rub, 5 rubs, and 10 rubs at three different places along the draw-down coating. The optical density of the original drawdown, the smeared area, and the paper background was determined with an X-Rite Model 428 Density Meter. The smear percent was calculated by taking the ' ° CA 02341113 2001-03-16 ratio of the optical density of the smeared area over the optical density of the drawdown, both corrected for paper background for each of the smeared areas.
HAZE TEST
The haze was determined with a Haze-Bard plus-Byk Gardner-Folio Co. using recommended testing conditions. The samples tested were prepared by the method described for the smear test except that a MylarO
film was used instead of paper.
CREASE TEST
The crease was determined by the method developed for xerographic print evaluation. More specifically, crease values were measured on solid area ink sample images on paper by (a) folding inwards the printed area of the image, (b) passing over the folded image a standard TEFLON~ coated copper roll 2 inches in width, 3 inches in outer diameter, 2.25 inches in inner diameter, and weighing 860 grams, (c) unfolding the paper and wiping the loose ink from the creased imaged surface with a cotton swab, and (d) measuring the average width of the ink free creased area with an image analyzer.

A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.4 gram of VERSAMIDO 963 (adhesive; amine terminated polyamide copolymer; obtained from Henkel), 1.12 grams of FORALO F-105 (tackifier, obtained from Hercules), 1.75 grams of UNION CAMPO UC-235 (clarifier, obtained from Union Camp), and 6.18 ' ' CA 02341113 2001-03-16 grams of KEMAMIDE~ S-180 (ink vehicle; obtained from Witco). The mixture was heated to 130°C for one hour until all of the components were melted.
While stirring with a magnetic stirrer, 0.55 gram of Duasyn Black A-RG VP280 black dye (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, crease, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 75.3 haze: 27.6 crease: 11 smear resistance after 1 rub: 0.93 smear resistance after 5 rubs: 3.06 smear resistance after 10 rubs: 3.70 EXAMPLE II
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.5 gram of VERSAMIDO 757 (adhesive; amine terminated polyamide copolymer; obtained from Henkel), 1.10 grams of FORALO F-105 (tackifier, obtained from Hercules), 1.63 grams of UNION CAMPO UC-235 (clarifier, obtained from Union Camp), and 6.21 grams of KEMAMIDEO S-180 (ink vehicle; obtained from Witco). The mixture was heated to 130°C for one hour until alt of the components were melted.
While stirring with a magnetic stirrer, 0.56 gram of Duasyn Black A-RG VP280 black dye (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. ft was then poured in a brass mold of 35 millimeters in diameter and 6.3 ' ' CA 02341113 2001-03-16 millimeters in thickness. The hardness, haze, crease, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 74.6 haze: 36.3 crease: 20 smear resistance after 1 rub: 0.96 smear resistance after 5 rubs: 3.85 smear resistance after 10 rubs: 6.38 EXAMPLE III
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.25 gram of VERSAMIDO 963 (adhesive; amine terminated polyamide copolymer; obtained from Henkel), 0.25 gram of VERSAMIDO 757 (adhesive; amine terminated polyamide copolymer; obtained from Henkel), 1.10 grams of FORALO F-105 (tackifier, obtained from Hercules), 1.63 gram of UNION CAMPO UC-235 (clarifier, obtained from Union Camp), and 6.21 grams of KEMAMIDEO S-180 (ink vehicle; obtained from Witco). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.56 gram of Duasyn Black A-RG VP280 black dye (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness.
The hardness, haze, crease, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 75.3 haze: 60.7 ' CA 02341113 2001-03-16 crease: 20 smear resistance after 1 rub: 2.44 smear resistance after 5 rubs: 3.60 smear resistance after 10 rubs: 7.69 EXAMPLE IV
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.25 gram of VERSAMIDO 963 (adhesive; amine terminated polyamide copolymer; obtained from Henkel), 0.25 gram of VERSAMIDO 744 (adhesive; amine terminated polyamide copolymer; obtained from Henkel), 1.10 grams of FORALO F-105 (tackifier, obtained from Hercules), 1.63 gram of UNION CAMPO UC-235 (clarifier, obtained from Union Camp), and 6.21 grams of KEMAMIDEO S-180 (ink vehicle; obtained from Witco). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.56 gram of Duasyn Black A-RG VP280 black dye (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness.
The hardness, haze, crease, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 72.2 haze: 31.2 crease: 17 smear resistance after 1 rub: 0.44 smear resistance after 5 rubs: 3.15 smear resistance after 10 rubs: 5.02 " CA 02341113 2001-03-16 rveum r t7 A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.0 grams of stearic acid, 4.62 grams of EP700 (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite), and 3.08 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.30 gram of Ceres Blue N dye (obtained from Bayer Co. ) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 70.4 haze: 53.3 smear resistance after 1 rub: 0.78 smear resistance after 5 rubs: 5.43 smear resistance after 10 rubs: 11.5 EXAMPLE VI
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.0 grams of octadecylamine, 4.62 grams of EP700 (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite), and 3.08 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite). The mixture was heated to ' " CA 02341113 2001-03-16 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.30 gram of Ceres Blue N dye (obtained from Bayer Co.) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 68.2 haze: 99.7 smear resistance after 1 rub: 5.56 smear resistance after 5 rubs: 6.42 smear resistance after 10 rubs: 9.57 EXAMPLE VII
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 1.0 gram of stearic acid, 1.0 gram of octadecylamine, 4.62 grams of EP700 (ink vehicle; polyethylene wax;
obtained from Baker Hughes, Petrolite), and 3.08 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.30 gram of Ceres Blue N dye (obtained from Bayer Co.) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 69.8 ' CA 02341113 2001-03-16 haze: 36.8 smear resistance after 1 rub: 5.22 smear resistance after 5 rubs: 10.66 smear resistance after 10 rubs: 13.33 As the data indicate, haze is substantially reduced when the octadecylamine and stearic acid are used in combination, compared to the inks containing only stearic acid (Example V) and only octadecylamine (Example VI).
EXAMPLE VIII
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.0 grams of the C~$-C~6 ink vehicle prepared in Synthesis I, 4.62 grams of EP700 (ink vehicle; polyethylene wax;
obtained from Baker Hughes, Petrolite), and 3.08 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.30 gram of Ceres Blue N dye (obtained from Bayer Co. ) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 71.5 haze:43.0 smear resistance after 1 rub: 5.3 smear resistance after 5 rubs: 12.3 smear resistance after 10 rubs: 13.7 ' CA 02341113 2001-03-16 EXAMPLE IX
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 1.0 gram of the C~8-C~6 ink vehicle prepared in Synthesis I, 1.0 gram of stearic acid, 4.62 grams of EP700 (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite), and 3.08 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.30 gram of Ceres Blue N dye (obtained from Bayer Co.) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 71.8 haze: 52.0 smear resistance after 1 rub: 6.8 smear resistance after 5 rubs: 11.5 smear resistance after 10 rubs: 14.4 EXAMPLE X
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.0 grams of octadecylamine, 2.0 grams of stearic acid, 3.45 grams of EP700 (ink vehicle; polyethylene wax;
obtained from Baker Hughes, Petrolite), and 2.25 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, ' ' CA 02341113 2001-03-16 Petrolite). The mixture was heated to 130°C for one hour until all of the components were melted. White stirring with a magnetic stirrer, 0.30 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 69.6 haze: 59.0 smear resistance after 1 rub: 3.1 smear resistance after 5 rubs: 4.8 smear resistance after 10 rubs: 6.3 rvAUm r V1 A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.5 grams of octadecylamine, 2.5 grams of stearic acid, 2.70 grams of EP700 (ink vehicle; polyethylene wax;
obtained from Baker Hughes, Petrolite), and 1.80 grams of VYBARO 103 (V-103) (ink vehicle; polyethylene wax; obtained from Baker Hughes, Petrolite). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.30 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 69.0 ' CA 02341113 2001-03-16 haze: 57.2 smear resistance after 1 rub: 2.4 smear resistance after 5 rubs: 6.1 smear resistance after 10 rubs: 11.2 EXAMPLE XII
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.0 grams of stearic acid and 7.5 grams of EPOLENEO N-14 (ink vehicle; polyethylene, molecular weight about 4,000; obtained from Eastman). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.50 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 69.3 haze: 59.6 smear resistance after 1 rub: 2.9 smear resistance after 5 rubs: 32.6 smear resistance after 10 rubs: 32.6 EXAMPLE XIII
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 2.0 grams of octadecylamine and ' ' CA 02341113 2001-03-16 7.5 grams of EPOLENEO N-14 (ink vehicle; polyethylene, molecular weight about 4,000; obtained from Eastman). The mixture was heated to 130°C
for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.50 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 66.9 haze: 98.0 smear resistance after 1 rub: 0.81 smear resistance after 5 rubs: 17.96 smear resistance after 10 rubs: 32.3 EXAMPLE XIV
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 1.0 gram of stearic acid, 1.0 gram of octadecylamine and 7.5 grams of EPOLENEO N-14 (ink vehicle;
polyethylene, molecular weight about 4,000; obtained from Eastman). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.50 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:

' CA 02341113 2001-03-16 hardness: 71.4 haze: 44.3 smear resistance after 1 rub: 2.0 smear resistance after 5 rubs: 8.6 smear resistance after 10 rubs: 14.4 As the data indicate, haze is substantially reduced and smear resistance is substantially improved when the octadecylamine and stearic acid are used in combination, compared to the inks containing only stearic acid (Example XLI) and only octadecylamine (Example XIII).
EXAMPLE XV
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 1.5 grams of stearic acid and 8.0 grams of the C~$-C~6 ink vehicle prepared in Synthesis I. The mixture was heated to 130°C for one hour until all of the components were melted.
While stirring with a magnetic stirrer, 0.50 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 74.0 haze: 63.7 smear resistance after 1 rub: 2.7 smear resistance after 5 rubs: 12.5 smear resistance after 10 rubs: 16.9 EXAMPLE XVI
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 1.5 grams of octadecylamine and 8.0 grams of the C,$-C~6 ink vehicle prepared in Synthesis I. The mixture was heated to 130°C for one hour until all of the components were melted.
While stirring with a magnetic stirrer, 0.50 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 65.7 haze: 90.7 smear resistance after 1 rub: 1.9 smear resistance after 5 rubs: 14.4 smear resistance after 10 rubs: 17.8 EXAMPLE XVII
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.75 gram of octadecylamine, 0.75 gram of stearic acid, and 8.0 grams of the C~$-C~6 ink vehicle prepared in Synthesis I. The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.50 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an ' CA 02341113 2001-03-16 hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The hardness, haze, and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
hardness: 72.6 haze: 53.5 smear resistance after 1 rub: 3.8 smear resistance after 5 rubs: 9.6 smear resistance after 10 rubs: 12.5 As the data indicate, haze is substantially reduced and smear resistance is substantially improved when the octadecylamine and stearic acid are used in combination, compared to the inks containing only stearic acid (Example XV) and only octadecylamine (Example XVI).
EXAMPLE XVIII
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.5 gram of stearic acid, 0.5 gram of the C~$-C$ urea ink vehicle prepared in Synthesis III, 5.97 grams of KEMAMIDEO S-180 (ink vehicle; obtained from Witco), 1.016 grams of FORALO F-105 (tackifier, obtained from Hercules), 1.335 grams of X37-523-235 (clarifier, obtained from Union Camp), and 0.126 gram of VERSAMIDO 963 (adhesive; amine terminated polyamide copolymer;
obtained from Henkel). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.554 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters ~ CA 02341113 2001-03-16 in diameter and 6.3 millimeters in thickness. The haze and smear resistance after 1 rub for this ink were as follows:
haze: 35.2 smear resistance after 1 rub: 5.5 EXAMPLE XIX
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.5 gram of stearic acid, 0.5 gram of EPOLENEO N-14 (ink vehicle; polyethylene, molecular weight about 4,000; obtained from Eastman), 5.97 grams of KEMAMIDE~ S-180 (ink vehicle; obtained from Witco), 1.016 grams of FORAL~ F-105 (tackifier, obtained from Hercules), 1.335 grams of X37-523-235 (clarifier, obtained from Union Camp), and 0.126 gram of VERSAMID~ 963 (adhesive; amine terminated polyamide copolymer; obtained from Henkel). The mixture was heated to 130°C for one hour until alt of the components were melted.
While stirring with a magnetic stirrer, 0.554 gram of Duasyn Black A-RG
VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The haze and smear resistance after 1 rub for this ink were as follows:
haze: 57.1 smear resistance after 1 rub: 5.3 " ' CA 02341113 2001-03-16 EXAMPLE XX
A 10 gram sample of ink was prepared by adding to an aluminum dish (diameter 5 centimeters) 0.5 gram of stearic acid, 0.5 gram of the C~$-C4 urea ink vehicle prepared in Synthesis II, 5.97 grams of KEMAMIDEO S-180 (ink vehicle; obtained from Witco), 1.016 grams of FORALO F-105 (tackifier, obtained from Hercules), 1.335 grams of X37-523-235 (clarifier, obtained from Union Camp), and 0.126 gram of VERSAMID~ 963 (adhesive; amine terminated polyamide copolymer;
obtained from Henkel). The mixture was heated to 130°C for one hour until all of the components were melted. While stirring with a magnetic stirrer, 0.554 gram of Duasyn Black A-RG VP280 (obtained from Clariant) was added to the molten mixture. The covered sample was further heated and stirred for an hour and a half. It was then poured in a brass mold of 35 millimeters in diameter and 6.3 millimeters in thickness. The haze and smear resistance after 1, 5, and 10 rubs for this ink were as follows:
haze: 54.7 smear resistance after 1 rub: 3.1 smear resistance after 5 rubs: 3.8 smear resistance after 10 rubs: 5.8 Other embodiments and modifications of the present invention may occur to those of ordinary skill in the art subsequent to a review of the information presented herein; these embodiments and modifications, as well as equivalents thereof, are also included within the scope of this invention.

Claims (30)

1. An ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher.

2. An ink composition according to claim 1 wherein the ink composition has a melting point of at least about 60°C and wherein the ink composition has a melting point of no more than about 160°C.

3. An ink composition according to claim 1 wherein the ink composition has a melting point of at least about 70°C and wherein the ink composition has a melting point of no more than about 140°C.

4. An ink composition according to claim 1 wherein the ink vehicle is (a) a carbamate of the formula C n H2n+1-NHCOO-C n H2n+1 or a biscarbamate of the formula C n H2n+1-OCONH-C n H2n-NHCOO-C n H2n+1 wherein n is an integer of from about 5 to about 20, said ink vehicle being solid at about 25°C, (b) an alkylated urea or an alkylated bis-urea, said ink vehicle being solid at about 25°C, (c) a monoamide, (d) a polyethylene, (e) an amine terminated polyamide copolymer, or (f) a mixture thereof.

5. An ink composition according to claim 1 wherein the ink vehicle is stearamide, behenyl benenamide, stearyl stearamide, polyethylene, stearylcarbamoyl stearate, stearylcarbamoyl octoate, stearylcarbamoyl dodecanoate, a stearylcarbamoyl hexadecanoate, or a mixture thereof.

6. An ink composition according to claim 1 wherein the ink vehicle is present in the ink in an amount of at least about 50 percent by weight of the ink and wherein the ink vehicle is present in the ink in an amount of no more than about 98 percent by weight of the ink.

7. An ink composition according to claim 1 wherein the ink vehicle is present in the ink in an amount of at least about 60 percent by weight of the ink and wherein the ink vehicle is present in the ink in an amount of no more than about 92 percent by weight of the ink.

8. An ink composition according to claim 1 wherein the colorant is a solvent soluble dye, a spirit soluble dye, or a mixture thereof.

9. An ink composition according to claim 1 wherein the colorant is a pigment.

10. An ink composition according to claim 1 wherein the colorant is present in the ink in an amount of at least about 0.5 percent by weight of the ink and wherein the colorant is present in the ink in an amount of no more than about 10 percent by weight of the ink.

11. An ink composition according to claim 1 wherein the anionic surfactant is (a) of the formula RCOOH or RCOO-B+, wherein R is an alkyl group and B is a cation, (b) of the formula HOOC-R-COOH, wherein R is an alkyl group, (c) an alkyl sulfate salt, (d) a sulfonated naphthalene-formaldehyde condensate salt, (e) a lignosulfonate salt, (f) a poly(methyl vinyl ether/maleic anhydride) salt, (g) of the formula ROSO3-B+ wherein R is an alkyl group and B is a cation, (h) of the formula R(OCH2CH2)n OSO3-B+
wherein n is an integer with an average value of from about 1 to about 4, R
is an alkyl group, and B is a canon, or (i) mixtures thereof.

12. An ink composition according to claim 1 wherein the anionic surfactant is palmitic acid, lauric acid, stearic acid, undecanedioic acid, sodium lauryl sulfate, sodium lauryl ether sulfate, or mixtures thereof.

13. An ink composition according to claim 1 wherein the anionic surfactant is stearic acid.

14. An ink composition according to claim 1 wherein the anionic surfactant is present in the ink in an amount of at least about 0.01 percent by weight and wherein the anionic surfactant is present in the ink in an amount of no more than about 50 percent by weight.

15. An ink composition according to claim 1 wherein the cationic surfactant is of the formula N(R1)x(R2)y(R3)z+A- wherein R1 and R2 each, independently of the other, are hydrogen atoms or alkyl groups, R3 is an alkyl group, an aryl group, an alkylaryl group, or an arylalkyl group, x, y, and z are integers wherein x is at least one and z is at least one and the sum of x+y+z=4, and A is an anion.

16. An ink composition according to claim 1 wherein the cationic surfactant is benzyl cetyl dimethyl ammonium chloride, hexadecyl trimethyl ammonium bromide, tetraheptyl ammonium bromide, octadecytamine, acetic acid salts of n-alkyl amines, stearamido amine, stearamido morpholine, palmitic amidoalkyl dimethyl amine, stearic amido alkyl dimethyl amine, substituted imidazoline from oleic acid, alkyl dimethyl benzyl ammonium saccharinate, dihydydrogenated tallow dimethyl ammonium chloride, dialuryl dimethyl ammonium bromide, n-octyl decylamine, or mixtures thereof.

17. An ink composition according to claim 1 wherein the cationic surfactant is octadecylamine.

18. An ink composition according to claim 1 wherein the cationic surfactant is present in the ink in an amount of at least about 0.1 percent by weight and wherein the anionic surfactant is present in the ink in an amount of no more than about 50 percent by weight.

19. An ink composition according to claim 1 wherein the anionic surfactant is stearic acid and the cationic surfactant is octadecylamine.

20. An ink composition according to claim 1 wherein the ink contains a nonionic surfactant which is ethoxylated lanolin alcohol, polyethylene glycol monostearate, or mixtures thereof.

21. An ink composition according to claim 1 wherein the ink contains a nonionic surfactant in an amount of at least 0.1 percent by weight of the ink and wherein the ink contains a nonionic surfactant in an amount of no more than about 20 percent by weight of the ink.

22. An ink composition according to claim 1 wherein the ink contains a conductivity enhancing agent in an amount of at least 1 percent by weight of the ink and wherein the ink contains a conductivity enhancing agent in an amount of no more than about 20 percent by weight of the ink.

23. An ink composition according to claim 1 wherein the ink contains an antioxidant in an amount of at least 0.01 percent by weight of the ink and wherein the ink contains an antioxidant in an amount of no more than about 2 percent by weight of the ink.

24. An ink composition according to claim 1 wherein the ink contains a UV absorber in an amount of at least 0.01 percent by weight of the ink and wherein the ink contains a UV absorber in an amount of no more than about 2 percent by weight of the ink.

25. An ink composition according to claim 1 wherein the ink has an acoustic loss value of no higher than about 100 decibels per millimeter.

26. An ink composition according to claim 1 wherein the ink has an acoustic loss value of no higher than about 60 decibels per millimeter and wherein the ink has an acoustic loss value of no lower than about 10 decibels per millimeter.

27. An ink composition according to claim 1 wherein the ink generates images having a hardness of no less than about 60.

28. An ink composition according to claim 1 wherein the ink generates images having a hardness of no less than about 60 and wherein the ink generates images having a hardness of no more than about 90.

29. A printing process which comprises (1) incorporating into a hot melt ink jet printing apparatus an ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV
absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher; (2) melting the ink; and (3) causing droplets of the melted ink to be ejected in an imagewise pattern onto a recording sheet.

30. A printing process which comprises (1) incorporating into an acoustic ink jet printing apparatus an ink composition comprising (a) an ink vehicle, (b) a colorant, (c) an anionic surfactant, (d) a cationic surfactant, (e) an optional nonionic surfactant, (f) an optional conductivity enhancing agent, (g) an optional antioxidant, and (h) an optional UV
absorber, said ink composition being solid at 25°C and having a melting point of about 60°C or higher; (2) melting the ink; and (3) causing droplets of the melted ink to be ejected by acoustic beams in an imagewise pattern onto a recording sheet.