JP2018505242A - ink - Google Patents

Abstract

(A) 0.5-5 parts self-dispersing pigment; (b) 2-8 parts styrene acrylic latex binder and / or styrene butadiene latex binder; (c) 0.5-5 parts polyurethane latex binder; d) 0-5 parts glycol selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol or triethylene glycol; (e) 1-10 parts 2-pyrrolidone; (f) 1-15 (G) 0.1-3 parts acetylenic surfactant; (h) 0.001-5 parts biocide; (i) 0-10 parts viscosity modifier; and (j) Ink containing up to 100 parts of excess water; Similarly, an inkjet printing method, an inkjet ink container, a printed substrate, and an inkjet printer. [Selection figure] None

Description

  The present invention relates to an ink, an inkjet printing method, an inkjet ink container, an ink set, and an inkjet printer.

Inkjet printing is a non-impact printing technique that ejects ink droplets through a fine nozzle onto a substrate without bringing the nozzle into contact with the substrate. There are basically three types of inkjet printing:
i) Continuous ink jet printing uses a pressurized ink source that provides a continuous flow of ink droplets from the nozzles. The ink droplets are directed at a nominally constant distance from the nozzle by either thermal or electrostatic means. Droplets that do not deflect well are recycled to the ink reservoir via the grooves.
ii) Drop-on-demand ink jet printing where ink is stored in a cartridge and fired from a print head nozzle using a pressure actuator (usually thermal or piezoelectric). Drop-on-demand printing results in only the drops that are needed for printing.
iii) Recirculating ink jet printing where ink is continually recirculated through the printhead and only the drops required for printing come out of the nozzles (similar to drop-on-demand printing).

  Each of these types of ink jet printing presents unique challenges. Thus, in continuous inkjet printing, solvent evaporation during the time of flight of droplets ejected from the nozzle but not producing a printed image (ie, the time between ejection from the nozzle and recycling in the groove), and Ink active solvent monitoring and adjustment is necessary to prevent solvent evaporation from the degassing process that removes excess air (which is drawn into the reservoir when recycling unused drops).

  In drop-on-demand printing, the ink may be retained in the cartridge for an extended period of time, when the ink degrades and forms a deposit that can clog the print head's fine nozzles when used. Sometimes. This problem is particularly acute with pigmented inks where suspended pigment particles can settle.

  These problems are avoided in recirculating ink jet printing. Since the ink is constantly circulating, the likelihood of pigment settling is reduced, and solvent evaporation is minimal because the ink moves to the nozzle only as needed to form an image.

  Recirculating ink jet printers find utility, especially in the industrial sector. Industrial inkjet printers are required to operate at high speeds. The print head of an industrial inkjet printing machine is optimal if it has a large number of nozzles arranged in a high density so as to enable high productivity single pass printing with acceptable print resolution.

  Ink formulations suitable for all forms of inkjet printing are extremely demanding. It is particularly difficult to formulate inks that can operate with these high speed single pass printheads. In order to allow these printers to operate at these high speeds, the inks used must exhibit low foaming and excellent drop formation.

Accordingly, the present invention provides a pigment ink formulated as follows:
(I) does not cause nozzle blockage in the recirculation head;
(Ii) Enables rapid drying due to higher volatility than standard inkjet inks. This is extremely important in industrial processes as it allows for high production rates with low energy consumption (ie low temperature printing);
(Iii) incorporating carefully selected latexes and optimizing ink vehicle design to provide a high quality image that is durable and comparable to flexographic printing;
(Iv) sufficiently stable and robust so that it can be used in a continuous industrial environment;
(V) does not cause foaming;
(Vi) Does not cause wetting of the face-plate in the print head.

  The wetting ability of a liquid is a function of its surface tension with respect to the surface energy of the solid surface. Thus, surface wetting occurs when liquid molecules have an attractive force on solid surface molecules that is stronger than an attractive force on each other (adhesion is stronger than cohesion). However, if the molecules in the liquid are attracted to each other more strongly than they are attracted to the molecules on the solid surface (cohesion is stronger than adhesion), the liquid becomes ball-like and does not wet the surface. The wetness of a liquid on a particular surface can be determined by measuring the contact angle of a droplet placed on the surface. The liquid is said to wet the surface when the contact angle is less than 90 degrees. The smaller the contact angle, the higher the wetness.

  The design of volatile inks that do not foam, do not wet the face plate of the print head, and contain latexes with low filming temperatures (required in (ii) and (iii)) is very difficult.

Therefore, according to the first aspect of the present invention,
(A) 0.5 to 5 parts of a self-dispersing pigment;
(B) 2-8 parts styrene acrylic latex binder and / or styrene butadiene latex binder;
(C) 0.5-5 parts polyurethane latex binder;
(D) 0 to 5 parts glycol selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol or triethylene glycol;
(E) 1-10 parts 2-pyrrolidone;
(F) 1-15 parts glycerol;
(G) 0.1 to 3 parts of an acetylenic surfactant;
(H) 0.001 to 5 parts biocide;
(I) 0-10 parts of viscosity modifier; and (j) up to 100 parts of residual water;
An ink containing the ink is provided.

  All parts and percentages herein are based on weight (unless otherwise noted).

  “Self-dispersing pigments” are pigment preparations that can be freely, rapidly and permanently dispersed when added to a liquid medium. If the pigment has charged groups on the surface (directly or via an associated polymer dispersant), it preferably has a counter ion.

  Self-dispersing pigments originate from any of the classes of pigments listed in the chapter entitled “Pigments” in the third edition of Color Index (1971), and subsequent revisions thereof, and its supplements. It is preferable.

  Examples of suitable organic pigments are azo (including disazo and condensed azo), thioindigo, indanthrone, isoindanthrone, antanthrone, anthraquinone, isodibenzanthrone, triphendioxazine, quinacridone, and phthalocyanine series, especially copper phthalocyanine And rakes of acidic, basic and mordant dyes, as well as those from their halogenated derivatives. Carbon black is often regarded as an inorganic substance, but in terms of dispersion characteristics, it behaves more like an organic pigment and is equally suitable. Preferred organic pigments are phthalocyanines, especially copper phthalocyanine pigments, azo pigments, indanthrone, antanthrone, quinacridone, and carbon black pigments.

  The pigment is preferably a yellow, cyan, magenta or black pigment. The pigment can be a single chemical species or a mixture comprising two or more chemical species (eg, a mixture comprising two or more different pigments). In other words, two or more different pigment solids can be used in the method of the present invention.

  More preferably, the self-dispersing pigment is selected from the group consisting of carbon black; Pigment Blue 15: 3; Pigment Blue 60; Pigment Yellow 74; Pigment Yellow 155; Pigment Red 254 and Pigment Red 122.

  The pigment in the self-dispersing pigment can be dispersed by any means known in the art. This can include coating the surface of the pigment with a suitable dispersant or mixture thereof. Dispersants can be anionic, cationic or nonionic and can include random, block or comb polymers. Suitable dispersants include but are not limited to poly (meth) acrylates, polyurethanes, polyesters and polyethers.

  Other preferred self-dispersing pigments can be prepared by chemically modifying the surface of the pigment. This is especially preferred for carbon black, which can oxidize the pigment surface to make the carbon black water dispersible. Suitable oxidants include air, hydrogen peroxide, hypochlorite, nitric acid, nitrogen dioxide, ozone and persulfate.

Accordingly, in a preferred embodiment of the present invention, the self-dispersing pigment is carbon black whose surface is oxidized.
Organic pigments can also have charged groups introduced on their surface using either reagents specific to that particular class / type of pigment or more general reactions such as sulfonation.

Alternatively, the self-dispersing pigment can have charged groups or polymer dispersants that are chemically covalently attached to its surface.
Thus, for example, carbon black can react with a diazonium salt. This makes it possible to introduce specific charged groups onto the surface of carbon black. Generally, a phenyl spacer group in which a charge / dispersing group is bonded to phenyl is used. Examples of such charged groups are sulfonates, carboxyls, phosphonates and biphosphonates. It is also possible to use the chemical action of diazonium to introduce certain polymer dispersants onto the surface of carbon black.

  Certain organic pigments can also have charged groups and polymer dispersants introduced on the surface via the diazonium chemistry. The dispersant attached to the surface of the self-dispersing pigment can be of any type known to those skilled in the art. Dispersants can be of general applicability or designed for use with specific pigments.

In a preferred embodiment of the present invention, the self-dispersing pigment is a pigment having a charged group or polymer dispersant that is covalently attached to the surface of the pigment by a diazonium compound.
One preferred form of dispersant is a diblock copolymer AB or a triblock copolymer ABA where block B has an affinity for the pigment and block A is involved in colloidal stabilization. . With organic pigments, it is possible to synthesize specific pigments containing such dispersants rather than attaching the dispersant to the pigments after the synthesis stage.

In component (a), the self-dispersing pigment preferably contains a dispersant that is crosslinked around the pigment.
In one particularly preferred embodiment of component (a), the self-dispersing pigment comprises at least two groups selected from oxetane, carbodiimide, hydrazide, oxazoline, aziridine, isocyanate, N-methylol, ketenimine, isocyanurate and epoxy groups, in particular A carboxy functional dispersant is crosslinked around the pigment core by a crosslinking agent having two or more epoxy groups.

The dispersant preferably has an acid value of at least 125 mg KOH / g before crosslinking with the crosslinking agent.
The dispersant preferably has one or more oligomer dispersing groups.

  In order to provide water dispersibility, it is preferred that the polymer encapsulated pigment particles have carboxy groups (ie, not all of the carboxy groups in the dispersant are crosslinked to form polymer encapsulated pigment particles).

  The polymer encapsulated pigment particles are prepared by crosslinking some of the carboxy groups in the carboxy functional dispersant in the presence of the pigment and the crosslinking agent, preferably at a temperature below 100 ° C. and / or a pH of at least 6. Can do. Such cross-linking is usually carried out in an aqueous medium, for example in a mixture comprising water and an organic solvent. Suitable mixtures comprising water and organic solvent are as described above for the ink.

The polymer encapsulated pigment particles preferably have a Z average particle size of less than 500 nm, more preferably 10 to 400 nm, especially 15 to 300 nm.
The Z average particle size can be measured by any means, but the preferred method is by a photon correlation spectrometer available from Malvern® or Coulter®.

  Suitable methods for making polymer encapsulated pigment particles are described in International Publications WO2006 / 064193 and WO2010 / 038071. Essentially, a pigment dispersion in which a dispersant having carboxy groups is adsorbed onto the pigment and then some (but not all) of the carboxy groups are crosslinked so that the pigment is permanently trapped within the crosslinked dispersant Get things. Such particles can be obtained commercially from FUJIFILM Imaging Colorants Limited.

The carboxy functional dispersant preferably comprises benzyl methacrylate.
Preferred carboxy functional dispersants are one or more hydrophobic ethylenically unsaturated monomers (preferably at least half of which are benzyl methacrylate based on weight) and one or more hydrophilic ethylenes having one or more carboxy groups. A copolymer comprising a water-soluble unsaturated monomer; optionally containing some or no hydrophilic ethylenically unsaturated monomer having one or more hydrophilic nonionic groups.

Particularly preferred carboxy functional dispersants are:
(I) 75-97 parts of one or more hydrophobic ethylenically unsaturated monomers comprising at least 50 parts benzyl methacrylate;
(Ii) 3 to 25 parts of one or more hydrophilic ethylenically unsaturated monomers having one or more carboxy groups; and (iii) 0 to 1 part hydrophilic ethylenic having one or more hydrophilic nonionic groups. Unsaturated monomers;
Said parts are based on weight;
Is a copolymer comprising

And typically, the sum of parts (i), (ii) and (iii) will be 100.
It is preferred that the only hydrophobic ethylenically unsaturated monomer of component (i) is benzyl methacrylate.

More preferably, the carboxy functional dispersant is
(I) 80-93 parts of one or more hydrophobic ethylenically unsaturated monomers comprising at least 50 parts benzyl methacrylate;
(Ii) 7 to 20 parts of one or more hydrophilic ethylenically unsaturated monomers having one or more carboxy groups;
(Iii) 0 to 1 part of a hydrophilic ethylenically unsaturated monomer having a hydrophilic nonionic group;
Said parts are based on weight;
Is a copolymer comprising

And typically, the sum of parts (i), (ii) and (iii) will be 100.
Preferably, the hydrophobic monomer does not have a hydrophilic group, whether it is ionic or nonionic. For example, they preferably have no water-dispersing groups.

The hydrophobic ethylenically unsaturated monomer preferably has a calculated log P of at least 1, more preferably 1-6, especially 2-6.
Mannhold, R.M. And Dross, K .; (Quant. Struct-Act. Relat. 15, 403-409, 1996) describes a method for calculating the log P value.

Preferred hydrophobic ethylenically unsaturated monomers are styrenic monomers (eg styrene and alphamethylstyrene), aromatic (meth) acrylates (especially benzyl (meth) acrylate), C _1-30 -hydrocarbyl (meth) acrylates, In addition to butadiene, they are (meth) acrylates containing poly (C _3-4 ) alkylene oxide groups, (meth) acrylates containing alkylsiloxanes or fluorinated alkyl groups, and vinyl naphthalene.

The dispersant preferably comprises 75 to 97, more preferably 77 to 97, especially 80 to 93, most particularly 82 to 91 parts by weight of repeating units derived from copolymerizing component (i).
Dispersants containing at least 50 parts of benzyl (meth) acrylate monomer repeating units can provide polymer encapsulated pigment dispersions with good stability and good optical density.

  Component (i) preferably comprises at least 60 parts by weight, more preferably at least 70 and especially at least 75 parts benzyl (meth) acrylate. The balance required to obtain the preferred total amount of hydrophobic monomers can be provided by any one or more of the above hydrophobic monomers other than benzyl (meth) acrylate. The benzyl (meth) acrylate is preferably benzyl methacrylate (not benzyl acrylate).

In a preferred embodiment, component (i) contains only benzyl (meth) acrylate, more preferably only benzyl methacrylate.
The monomer of component (ii) is preferably less than 1, more preferably from 0.99 to -2, especially from 0.99 to 0, most particularly from 0.8, calculated in the unneutralized (eg free acid) form. It has a log p calculation of 99-0.5.

  Preferred hydrophilic ethylenically unsaturated monomers for component (ii) having one or more carboxylic acid groups include beta carboxyl ethyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, more preferably acrylic acid, especially methacrylic acid. Is mentioned. These ethylenically unsaturated monomers preferably provide the only ionic group in the dispersant when polymerized.

In a preferred embodiment, component (ii) is methacrylic acid or contains methacrylic acid.
The dispersant preferably comprises repeating units derived from copolymerizing 3 to 25, more preferably 3 to 23, in particular 7 to 20, most particularly 9 to 18 parts by weight of component (ii). This is especially true when component (ii) contains methacrylic acid, more preferably methacrylic acid.

  For the purposes of the present invention, monomers having both ionic and nonionic hydrophilic groups are considered to belong to component (iii). Therefore, all of the ethylenically unsaturated monomers of component (ii) do not have hydrophilic nonionic groups.

The monomer of component (iii) preferably has a calculated log P of less than 1, more preferably 0.99 to -2.
Component (iii) is preferably less than 1 part, more preferably less than 0.5 part, especially less than 0.1 part, most especially 0 part (ie absent). Thus, the dispersant does not contain repeating units derived from hydrophilic monomers having one or more hydrophilic nonionic groups.

  Examples of hydrophilic nonionic groups include polyethyleneoxy, polyacrylamide, polyvinyl pyrrolidone, hydroxy functional cellulose, and polyvinyl alcohol. The most common ethylenically unsaturated monomer having a hydrophilic nonionic group is polyethyleneoxy (meth) acrylate.

  In embodiments where repeating units derived from component (iii) are present in the dispersant (eg, 1 part by weight of component (iii)), in one embodiment, the amount of component (iii) is subtracted from the preferred amount of component (i). . Thus, the amounts of all components (i), (ii) and (iii) still total 100. Thus, in the embodiment where 1 part by weight of component (iii) is present, the preferred amount of component (i) described above is 74-96 (75-1-97-1), more preferably 76-96 ( 77-1 to 97-1), especially 79 to 92 (80-1 to 93-1), most particularly 81 to 90 (82-1 to 91-1) parts by weight of component (i). In other embodiments, the amount of component (iii) can be subtracted from the preferred amount of component (ii) so that the sum of the amounts of components (i), (ii) and (iii) is likewise 100 Parts by weight.

  The function of the carboxylic acid group (s) in the dispersant is primarily to provide polymer encapsulated pigment particles that have the ability to crosslink with the crosslinker and subsequently disperse in the aqueous ink medium. If the carboxylic acid group (one or more) is the only group to stabilize the polymer encapsulated pigment particles in an aqueous medium, the crosslinker ensures that unreacted carboxylic acid groups remain after the crosslinking reaction is complete. It is preferable to have a molar excess of the carboxylic acid group with respect to the carboxy-reactive group (for example, epoxy group). In one embodiment, the ratio of moles of carboxylic acid groups to moles of carboxy reactive groups (eg epoxy groups) in the cross-linking agent is preferably 10: 1 to 1.1: 1, more preferably 5: 1 to 1. .1: 1, particularly preferably 3: 1 to 1.1: 1.

The dispersant may have other stabilizing groups. The choice of stabilizing group and the amount of such group are highly dependent on the nature of the aqueous medium.
In embodiments where the cross-linking agent has one or more oligomeric dispersing groups, the dispersing agent preferably has an acid value of at least 125 mg KOH / g.

  The acid value of the dispersant before crosslinking with the crosslinking agent is preferably 130 to 320, more preferably 135 to 250 mg KOH / g. In addition to showing good stability in aqueous inks, dispersants with such acid values result in polymer encapsulated pigment particles that have sufficient carboxy groups for subsequent crosslinking with the crosslinking agent. I found. The dispersant (before crosslinking) preferably has a number average molecular weight of 500 to 100,000, more preferably 1000 to 50000, and particularly 1000 to 35000. The molecular weight can be measured by gel permeation chromatography.

  The dispersant need not be completely dissolved in the liquid medium used to make the polymer encapsulated pigment particles. That is, a completely transparent and non-scattering solution is not essential. The dispersant may condense into surfactant-like micelles, resulting in a slightly turbid solution in the liquid medium. The dispersant may be such that some proportion of the dispersant tends to form a colloidal or micellar phase. The dispersant preferably provides a uniform and stable dispersion in the liquid medium used to make the polymer encapsulated pigment particles that does not settle or separate upon standing.

The dispersant is preferably substantially dissolved in the liquid medium used to make the polymer encapsulated pigment particles, resulting in a clear or cloudy solution.
Preferred random polymeric dispersants tend to give clear compositions, but less preferred polymeric dispersants with two or more segments tend to produce turbid compositions as described above in liquid media.

  Typically, the dispersant is adsorbed onto the pigment prior to crosslinking to form a relatively stable pigment particle dispersion. The dispersion is then cross-linked using a cross-linking agent to form polymer encapsulated pigment particles. This pre-adsorption and pre-stabilization, among other things, distinguishes the present invention from the coacervation approach. In the coacervation approach, a polymer or prepolymer (not a dispersant) is mixed with a particulate solid, a liquid medium and a crosslinking agent, and the resulting crosslinked polymer precipitates on the particulate solid only during or after crosslinking.

  In embodiments where the dispersant has an acid value of at least 125 mg KOH / g, the cross-linking agent may not have an oligomer dispersing group, but the cross-linking agent preferably has one or more oligomer dispersing groups.

Crosslinking agents having one or more oligomeric dispersing groups improve the stability of the polymer encapsulated pigment particles in the ink.
The oligomer dispersing group is preferably a polyalkylene oxide, more preferably a poly C _2-4 -alkylene oxide, in particular polyethylene oxide. The polyalkylene oxide groups provide steric stabilization that improves the stability of the resulting encapsulated particulate solid.

The polyalkylene oxide preferably contains 3 to 200, more preferably 5 to 50 alkylene oxides, especially 5 to 20 alkylene oxide repeating units.
The crosslinking agent preferably has at least two epoxy groups.

  Preferred crosslinkers having two epoxy groups and no oligomer dispersing groups are ethylene glycol diglycidyl ether, resorcinol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, and polybutadiene diglycidyl ether.

  Preferred crosslinkers having two epoxy groups and one or more oligomeric dispersing groups are diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether.

  Preferred crosslinkers having 3 or more epoxy groups and no oligomer dispersing groups are sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, and triglyceryl ether. Methylolpropane polyglycidyl ether.

In one embodiment, the epoxy crosslinker does not have an oligomer dispersing group.
Examples of oxetane crosslinkers include 1,4-bis [(3-ethyl-3-oxetanylmethoxymethyl)] benzene, 4,4′-bis [(3-ethyl-3-oxetanyl) methoxy] benzene, 1, 4-bis [(3-ethyl-3-oxetanyl) methoxy] benzene, 1,2-bis [(3-ethyl-3-oxetanyl) -methoxy] benzene, 4,4-bis [(3-ethyl-3- Oxetanyl) methoxy] biphenyl and 3,3 ′, 5,5′-tetramethyl- [4,4′-bis (3-ethyl-3-oxetanyl) methoxy] biphenyl.

  An example of a carbodiimide crosslinking agent is the crosslinking agent CX-300 from DSM NeoResins. A carbodiimide crosslinking agent having good solubility or dispersibility in water can also be prepared as described in Synthesis Examples 1 to 93 of US Pat. No. 6,124,398.

  Examples of isocyanate crosslinking agents include isophorone diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, methylene diphenyl diisocyanate, methylene dicyclohexyl diisocyanate, 2-methyl-1,5-pentane diisocyanate, 2,2,4-trimethyl-1,6-hexane. Diisocyanate and 1,12-dodecane diisocyanate, 1,11-diisocyanatoundecane, 1,12-diisocyanatododecane, 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexane 1,3-diisocyanatocyclobutane, 4,4′-bis- (isocyanatocyclohexyl) -methane, hexamethylene diisocyanate, 1,2-bis- (isocyanatomethyl) -cyclobutane, 1, -And 1,4-bis- (isocyanatomethyl) cyclohexane, hexahydro-2,4- and / or -2,6-diisocyanatotoluene, 1-isocyanato-2-isocyanatomethylcyclopentane, 1-isocyanato- 3-isocyanatomethyl-3,5,5-trimethyl-cyclohexane, 2,4′-dicyclohexylmethane diisocyanate, and 1-isocyanato-4 (3) -isocyanatomethyl-1-methylcyclohexane, tetramethyl-1,3 -And / or-1,4-xylylene diisocyanate, 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6-toluene diisocyanate, 2,4- and / or 4, 4'-diphenyl-methane diisocyanate, 1,5-diiso And cyanatonaphthalene and p-xylylene diisocyanate. Suitable diisocyanates are also understood to include those containing modifying groups such as biuret, uretdione, isocyanurate, allophanate and / or carbodiimide groups, as long as they contain two or more isocyanate groups. In the case of isocyanates, the liquid medium is preferably non-aqueous, but in some cases water may be acceptable with blocked isocyanates.

  In a preferred embodiment, the polyisocyanate crosslinker contains three isocyanate groups. A convenient source of triisocyanate functional compounds is the known isocyanurate derivatives of diisocyanates. Isocyanurate derivatives of diisocyanates can be made by reacting diisocyanates with a suitable trimerization catalyst. An isocyanurate derivative is obtained containing an isocyanurate core having an organic side chain terminated with three isocyanate groups. Several isocyanurate derivatives of diisocyanate are commercially available. In a preferred embodiment, the isocyanurate used is isocyanurate of isophorone diisocyanate. In another preferred embodiment, isocyanurate of hexamethylene diisocyanate is used.

  Examples of N-methylol crosslinkers include dimethoxydihydroxyethylene urea; N, N-dimethylol ethyl carbamate; tetramethylol acetylene diurea; dimethylol uron; dimethylol ethylene urea; dimethylol propylene urea; dimethylol adipic amide ( dimethylol adipic amide); and mixtures containing two or more thereof.

Examples of ketene imine crosslinkers include the formula Ph ₂ C═C═N—C ₆ H ₄ —N═C = CPh ₂ wherein each Ph is independently a phenyl group that may be substituted. ] Of the compound.

  Examples of hydrazide crosslinking agents include malonic acid dihydrazide, ethylmalonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, isophthalic acid dihydrazide, oxalyl dihydrazide and pimelic acid dihydrazide.

  A commercially available highly reactive oxazoline cross-linking agent is available, for example, under the trademark Epocross® from Nippon Shokubai. These are emulsion types (e.g., Epocross K-2000 series such as K-2010E, K-2020E and K-2030E) and water soluble types (e.g. Epocross WS series such as WS-300, WS-500 and WS-700). ).

  Examples of aziridine crosslinkers include ethyleneimine based polyaziridines (eg, PZ-28 and PZ-33 available from PolyAziridine LLC, Medford, NJ); XC-103 trifunctional aziridine, XC-105 polyfunctional Aziridine and crosslinker XC-113 (available from Shanghai Zealchem CO., Ltd., China); multifunctional aziridine liquid crosslinker SaC-100 (available from Shanghai UN Chemical Co., Ltd., China); Aziridine crosslinkers disclosed in WO2009 / 120420; NeoCryl® CX-100 (available from DSM NeoResins); Xama® multifunctional aziridine (Lu) available from rizol); trimethylolpropane tris (beta-aziridino) propionate, neopentyl glycol di (beta-aziridino) propionate, glyceryl tris (beta-aziridino) propionate, pentaerythrityl tetra (beta-aziridino) propionate, 4, 4'-isopropylidenediphenoldi (beta-aziridino) propionate, 4,4'-methylenediphenoldi (beta-aziridino); and mixtures containing two or more thereof.

  Particularly preferred cross-linking agents are polyethylene glycol diglycidyl ethers (for example those having an average molecular weight of 526 and which can be obtained from Aldrich) and / or trimethylolpropane polyglycidyl ethers (for example Denacol which can be obtained from Nagase Chemtex ( (Registered trademark) EX-321, the weight per epoxy is 140).

Component (a) is preferably present in the range of 0.75-4 parts, more preferably 1-3 parts.
The ink may contain more than one styrene acrylic latex binder and / or styrene butadiene latex binder (component (b)). Latex binders can differ in properties such as particle size, glass transition temperature or molecular weight.

  However, the styrene acrylic latex binder and / or styrene butadiene latex binder is preferably either a styrene acrylic latex binder or a styrene butadiene latex binder. More preferably, component (b) is a styrene acrylic latex binder.

The styrene acrylic latex binder preferably has a Tg in the range of -30 ° C to 50 ° C, more preferably in the range of 0 ° C to 40 ° C, particularly in the range of 10 ° C to 30 ° C.
The styrene butadiene latex binder preferably has a Tg in the range of 0 ° C to 120 ° C, more preferably in the range of 10 ° C to 110 ° C, especially in the range of 50 ° C to 90 ° C.

  Tg is determined by differential scanning calorimetry with dry latex. Tg is considered the midpoint value from the reheat differential scanning calorimetry scan (ie, after initial heating and cooling).

The styrene acrylic latex preferably has an acid value in the range of 5 to 100 mg KOH / g, more preferably in the range of 30 to 70 mg KOH / g.
The styrene acrylic latex binder and / or styrene butadiene latex binder is preferably prepared by emulsion polymerization.

  The molecular weight of the styrene acrylic latex binder and styrene butadiene latex binder can be determined by methods known in the art, such as the use of chain transfer agents (eg mercaptans) and / or in the case of emulsion polymerization, control of initiator concentration, and / or heating time. Can be controlled. The styrene acrylic latex binder and the styrene butadiene latex binder preferably have a molecular weight greater than 20000 Dalton, more preferably greater than 100,000 Dalton. It is particularly preferred that the molecular weight of the styrene acrylic latex binder and the styrene butadiene latex binder is greater than 200,000 to 500,000 daltons.

  Styrene acrylic latex binders and styrene butadiene latex binders can be unimodal and preferably have an average particle size of less than 1000 nm, more preferably less than 200 nm, especially less than 150 nm. The average particle size of the styrene acrylic latex binder and the styrene butadiene latex binder is preferably at least 20 nm, more preferably at least 50 nm. Accordingly, the styrene acrylic latex binder and the styrene butadiene latex binder can preferably have an average particle size in the range of 20 to 200 nm, more preferably in the range of 50 to 150 nm. The average particle size of the styrene acrylic latex binder and the styrene butadiene latex binder can be measured using photon correlation spectroscopy.

  Styrene acrylic latex binders and styrene butadiene latex binders can also exhibit a bimodal particle size distribution. This can be achieved by mixing two or more latexes of different particle sizes or by generating a bimodal distribution directly, for example by two-stage polymerization. When using a bimodal particle size distribution, the lower peak of the particle size is preferably in the range of 20-80 nm and the upper peak of the particle size is preferably in the range of 100-500 nm. More preferably, the ratio of the two particle sizes is at least 2, more preferably at least 3, and most preferably at least 5.

  The molecular weight of the styrene acrylic latex binder and styrene butadiene latex binder can be determined by gel permeation chromatography against polystyrene standards using an Agilent HP1100 instrument, THF as eluent, and a PL mixed gel C column.

  Once formed, the styrene acrylic latex binder and styrene butadiene latex binder have an average pore size of, for example, less than 3 μm, preferably 0.3-2 μm, especially 0.5-1.5 μm, in order to remove too large particles before use. It is preferred to screen through a filter having The styrene acrylic latex binder and styrene butadiene latex binder can be sieved before, during, or after mixing with the other ingredients to form the ink.

Commercially available styrene acrylic latex binders and styrene butadiene latex binders may be used in the ink according to the present invention.
Examples of commercially available styrene acrylic latex binders and styrene butadiene latex binders that can be used in the inks of the present invention include the Rovene® type of styrene acrylic latex supplied by Mallard Creek polymers, especially the Rovene 6102, Rovene 6112. And Rovene 6103, and styrene butadiene latexes such as Rovene 5499 and Rovene 4111.

Component (b) is preferably in the range of 5 to 8 parts.
Component (c) is a polyurethane latex binder.
Polyurethane dispersions are typically
(I) a polymer diol (polyol), and optionally other components capable of reacting with isocyanate groups, are reacted with a diisocyanate to make a prepolymer, followed by
(Ii) the prepolymer is optionally chain extended and dispersed in water by reacting with water and / or a chain extender present in the aqueous phase;
To make.

The dispersion can be stabilized by monomers present in the polyurethane, such as ionic or nonionic groups, or by added surfactants.
The Tg of the polyurethane latex binder can be controlled by the choice of polyol, di-isocyanate and chain extender. The Tg of the polyurethane binder latex can also be controlled by mixing batches of latex having different Tg.

The polyurethane latex binder preferably has a Tg in the range of −30 ° C. to 0 ° C.
The weight average molecular weight of the polyurethane is preferably> 20000, more preferably> 50000, most preferably> 100,000.

  The polyurethane latex binder preferably has an average particle size of less than 1000 nm, more preferably less than 200 nm, in particular less than 150 nm. The average particle size of the latex binder is preferably at least 20 nm, more preferably at least 50 nm. Accordingly, the latex binder preferably has an average particle size in the range of 20 to 200 nm, more preferably in the range of 50 to 150 nm. The average particle size of the latex binder can be measured using photon correlation spectroscopy.

  Commercial polyurethane latex binders include W835 / 177 and A835 / 397 from Incorez, Joncryl® U4190 from BASF, and Sancure® 20025F and Sancure 2710 from Lubrizol.

  Component (c) is preferably present in the range of 1 to 3 parts. Latex binders play an important role with respect to the improved adhesion seen when the inks of the present invention are applied to low surface energy substrates and the durability of the prints in wet and oily states.

  Latex binders (b) and (c) play an important role with respect to the improved adhesion seen when the inks of the present invention are applied to low surface energy substrates and the durability of the prints in wet and oily states. Fulfill.

Component (d) is preferably either ethylene glycol or triethylene glycol.
Component (d) is preferably present in the range of 0.5 to 2.5 parts, more preferably in the range of 0.75 to 2.0 parts.

Component (e) is preferably present in the range of 2.5 to 7.5 parts.
Component (f) is preferably present in the range of 2 to 7.5 parts.
Any acetylenic surfactant can be used as component (g). However, 2,4,7,9-tetramethyl-5-decyne-4,7-diol and its ethylene oxide condensate and 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol and its Ethylene oxide condensates are preferred.

  The acetylenic surfactant is particularly preferably 2,4,7,9-tetramethyl-5-decyne-4,7-diol or an ethylene oxide condensate thereof. The acetylene surfactant is particularly preferably 2,4,7,9-tetramethyl-5-decyne-4,7-diol. Surfactant 2,4,7,9-tetramethyl-5-decyne-4,7-diol and its ethylene oxide condensate are commercially available from Air Products as Surfynol (R) type surfactants.

  The preferred surfactant 2,4,7,9-tetramethyl-5-decyne-4,7-diol is available from Air Products as Surfynol® 440 or as its ethoxylated analog Surfynol® 465. Are commercially available.

Mixtures containing various surfactants may be used.
Component (g) is preferably in the range of 0.001 to 2.5 parts, more preferably 0.01 to 1.5 parts, especially 0.05 to 1.0 parts, and even more preferably 0. It exists in the range of 1 to 0.5 part.

  Surfactant is an important component of the ink of the present invention. Proper selection of both the surfactant and its concentration in the particular ink is essential to effectively eject the ink and not wet the printhead faceplate.

It is very important that the surfactant does not cause the ink to foam.
It is also desirable that the ink be designed to not wet the face plate of the print head that has not been treated with a “non-wetting coating”. These faceplates can exhibit a contact angle with water of less than 90 ° or less than 80 °. Faceplates specially designed to be non-wetting can have a contact angle with water that is greater than 90 °, in some cases greater than 95 °, and in some cases even greater than 100 °.

  In order to achieve these properties, it is desirable that the ink exhibits a dynamic surface tension range, i.e., the surface tension depends on the surface age. Although the surface tension of the newly created surface is high, drops such as surfactants or other surface active species migrate to the surface. The dynamic surface tension range can be determined by measurement with a bubble tensiometer. This measures surface tension as a function of surface life or bubble frequency. The surface tension measured at 5 ms (γ (5)) is> 35 dynes / cm, the surface tension measured at 1000 ms (γ (1000)) is in the range of 20-40 dynes / cm, and γ (10)> Gamma (1000) is preferred. Alternatively, the equilibrium surface tension of the ink can be compared to an equivalent ink made without the surfactant (one or more). Preferably, the equilibrium surface tension without surfactant is at least 10 dynes / cm higher than when surfactant (one or more) is present (singular or plural).

  With respect to component (h), any biocide (or mixture of biocides) that is stable in the ink can be used. Biocides are 1,2-benzisothiazolin-3-one available as a 20% active solution from Lonza as Proxel® GXL, and Bioban®, DXN (2,6 from Dow Chemical Company) -Dimethyl-1,3-dioxane-4-yl acetate) is particularly preferred.

  Component (i), which is a viscosity modifier, includes polyethers (such as polyethylene glycol and poly (ethylene oxide)), cellulose polymers such as hydroxyethyl cellulose, hydroxypropyl cellulose and carboxymethyl cellulose, water-soluble polyesters, and homopolymers of 2-ethyl-oxazoline. It is preferably selected from the group consisting of (eg poly-2-ethyl-2-oxazoline), poly (vinyl alcohol) and poly (vinyl pyrrolidone) and mixtures thereof.

  Component (i) is preferably poly (ethylene glycol) or poly (ethylene oxide). More preferably, component (h) is polyethylene glycol, especially polyethylene glycol 20000.

Component (i) is preferably present in the composition in an amount of 3-8 parts.
The ink preferably has an MFFT of less than 65 ° C, especially less than 60 ° C.
MFFT is the lowest temperature at which various components of the ink component fuse to form a film, for example, during ink drying.

  Measurement equipment for MFFT is commercially available, for example, Minimum Film Forming Temperature Bar is available from Rhopoint Instruments (“MFFT Bar90”). The MFFT Bar 90 includes a temperature bar having a nickel-plated copper surface plate that is electronically imposed with a temperature gradient. Ten equally spaced sensors below the surface instantaneously measure the temperature along the bar. Select the desired temperature program and allow the instrument to reach thermal equilibrium. The damp test ink trail can be applied using a cube applicator or spreader. When the ink is dry, the instrument shows MFFT. If for some reason the above-mentioned commercial equipment is not effective for ink (eg due to low latex content and / or ink color), a small amount of ink is placed on the dish instead and a dish with ink is preferred After heating at an evaluation temperature (for example, 70 ° C.) for 24 hours, it is possible to evaluate whether a film is formed by rubbing the surface with a gloved finger. Little or no ink is transferred to the gloved finger when the film is formed, but there is considerable ink transfer to the gloved finger or cracked dry ink when the film is not formed .

  The desired MFFT can be achieved by selecting a suitable combination of polymer latex and organic solvent. If the MFFT of the ink is too high, the amount of fusion solvent can be increased and / or a lower Tg polymer latex can be used to bring the ink MFFT to the desired range. Thus, at the ink design stage, depending on the desired MFFT, it can be determined whether to include more or less fusion solvent and higher or lower Tg polymer latex.

  Typically, the ink and substrate are selected so that the ink has a MFFT below the temperature at which the substrate deforms, warps or melts. In this way, the ink can form a film on the substrate at a temperature that does not damage the substrate.

In a first preferred embodiment, the viscosity of the ink at 32 ° C. is in the range of 10-14 mPa s as measured using Brookfield SC4-18 at 150 rpm.
In a second preferred embodiment, the viscosity of ink 1 at 32 ° C. is in the range of 4-8 mPas as measured using Brookfield SC4-18 at 150 rpm.

  In a first preferred embodiment, the ink is 20-65 dynes / cm, more preferably 20-50 dynes / cm, especially 32-42 dynes / cm, as measured at 25 ° C. using a Kruss K100 tensiometer, In particular, it has a surface tension of 34-38 dynes / cm.

  In a second preferred embodiment, the ink has a surface of 20-65 dynes / cm, more preferably 20-50 dynes / cm, especially 30-40 dynes / cm as measured at 25 ° C. using a Kruss K100 tensiometer. Has tension.

The ink composition is preferably filtered through a filter having an average pore size of less than 10 microns, more preferably less than 5 microns, especially less than 1 micron.
The ink preferably has a pH in the range of 7.5 to 9.5. The pH can be adjusted with a suitable buffer.

  In addition to the above components, the ink composition may optionally include one or more ink additives. Preferred additives suitable for ink jet printing inks are anti-kogation agents, rheology modifiers, corrosion inhibitors and chelating agents. The total amount of all such additives is preferably 10 parts by weight or less. These additives are added to and constitute part of component (j), the water added to the ink.

In a preferred embodiment, the ink is
(A ′) 0.75 to 4 parts of a self-dispersing pigment;
(B ′) 4-10 parts styrene acrylic latex binder;
(C ′) 1-3 parts polyurethane latex binder (d ′) 0.5-2.5 parts ethylene glycol;
(E ') 2.5-7.5 parts 2-pyrrolidone;
(F ′) 2 to 7.5 parts of glycerol;
(G ′) 0.05 to 1.0 part 2,4,7,9-tetramethyl-5-decyne-4,7-diol;
(H ′) 0.001 to 2 parts biocide;
(I ′) 3-8 parts viscosity modifier;
(J ′) up to 100 parts of residual water;
including.

In a second preferred embodiment, the ink of the present invention has no glycol. That is, component (d) is zero.
The present invention is particularly useful for printing substrates that are non-absorbent and / or temperature sensitive, but can also be used to print substrates that are absorbent and / or non-temperature sensitive. For such substrates, the present inks and methods provide the advantage of providing prints with good friction fastness properties at temperatures lower than those used in conventional methods, thereby reducing manufacturing costs.

  Examples of non-absorbing substrates include polyester, polyurethane, bakelite, polyvinyl chloride, nylon, polymethyl methacrylate, polyethylene terephthalate, polypropylene, acrylonitrile-butadiene-styrene, polycarbonate, about 50% polycarbonate and about 50% acrylonitrile. -Butadiene-styrene blends, polybutylene terephthalate, rubber, glass, ceramics and metals.

In one aspect, the ink of the present invention is particularly preferably used for printing on a substrate comprising a low density polyethylene film.
In another preferred embodiment, the ink is preferably used to print a substrate comprising a spunbond laminate film, particularly a polypropylene-based spunbond laminate film.

  It is particularly preferred that the ink be used to print a nonwoven wipe, preferably comprising polypropylene, more preferably a nonwoven wipe comprising a spunbond laminate film based on polypropylene.

  If desired, the substrate can be pretreated using, for example, plasma, corona discharge, or surfactant treatment to enhance ink adhesion to the substrate. For example, the substrate can be roughened or the substrate can be coated with an ink receptive coating.

In one embodiment, the method further comprises drying the ink applied to the substrate at a temperature of 70 ° C. or lower, more preferably 65 ° C. or lower, especially 60 ° C. or lower.
According to a second aspect of the present invention, there is provided an ink jet printing method in which an ink according to the first aspect of the present invention is printed on a substrate by an ink jet printer. In the second aspect of the present invention, it is preferable to print the ink according to the first aspect of the present invention on a substrate using an ink jet printer having an ink recirculating print head.

  Any ink jet printer with an ink recirculating printhead can be used in the process of the present invention. The print head preferably has an ink recirculation channel in the ink supply system. This channel allows unused ink to be made available for ejection and can be part of an ink supply system or can be a specially processed channel that extends behind the nozzle plate. The ink supply system preferably extends behind the nozzle plate so that more volatile ink can be used without adversely affecting restart / latency behavior. Recirculation behind the nozzle plate has been demonstrated with commercially available FUJIFILM Dimatix print heads such as Samba® or SG1024®.

  A preferred type of recirculating print head for the present invention typically comprises a reservoir heater and a thermistor for controlling the jetting temperature. In stage (III), the jetting temperature is preferably above 30 ° C.

The ink droplet volume applied by the ink jet printer is preferably in the range of 1 to 100 pL.
When ejecting the ink of the first preferred embodiment described above in step (I), the volume of ink droplets applied by an ink jet printer is preferably in the range of 20-100 pL, more preferably 20-40 pL, especially 25-35 pL. It is in the range.

  When ejecting the ink of the second preferred embodiment described above in step (I), the volume of ink droplets applied by the ink jet printer is preferably in the range of 1-20 pL, more preferably in the range of 2-8 pL.

  A third aspect of the present invention provides a substrate printed by the ink jet printing method described in the second aspect of the present invention using the ink described in the first aspect of the present invention. This substrate is as described and preferred in the first aspect of the present invention.

Thus, in one aspect, the printed substrate preferably comprises a low density polyethylene film.
In a second embodiment, the printed substrate is preferably a substrate comprising a spunbond laminate film, in particular a polypropylene-based spunbond laminate film.

  More preferably, in the second aspect, the printed substrate comprises a nonwoven wipe, preferably comprising polypropylene, more preferably comprising a spunbond laminate film based on polypropylene.

  In accordance with a fourth aspect of the present invention, there is provided an ink container (eg, a cartridge or a larger ink tank) for an ink jet printer that contains the ink defined in the first aspect of the present invention.

  A fifth aspect of the present invention includes the recirculation type print head described in the second aspect of the present invention and the ink container for an ink jet printing machine containing the ink described in the fourth aspect of the present invention. An ink jet printer is provided.

  A sixth aspect of the present invention is an ink set comprising black ink, cyan ink, yellow ink and magenta ink, wherein the ink is as described and preferred in the first aspect of the present invention. Provide an ink set. Preferably, the pigment in the black ink is carbon black; the pigment in the cyan ink is Pigment Blue 15: 3; the pigment in the yellow ink is Pigment Yellow 74 (or Pigment Yellow 155); in the magenta ink The pigment is Pigment Red 122. The ink set can also contain blue ink and red ink. Preferably, the pigment in the blue ink is Pigment Blue 60 and the pigment in the red ink is Pigment Red 254.

The invention will now be illustrated by the following examples. In this regard, all parts are based on weight unless otherwise specified.
The self-dispersing pigment used was Pro-Jet® APD 1000 black. The same ink can be prepared using Pro-Jet® APD 1000 cyan, magenta, yellow and yellow LF, red and blue. Pro-Jet® APD 1000 pigment dispersion is available from FUJIFILM Imaging Colorants Limited.

Surfynol® 440 and 465 are acetylenic surfactants from Air Products.
Ravene® 6102 is a styrene acrylic dispersion from Mallard Creek Polymers. The Rene 6102 has a Tg of 20 ° C. and an acid value of 50 mg KOH / g.

Sancure® 20025F is an aliphatic polyester urethane polymer dispersion from Lubrizol.
NeoRez® R-551 is a polyurethane dispersion from DSM.

  1,2-Benzisothiazolin-3-one was obtained from Lonza as Proxel® GXL (20% solution).

  Example inks 1 and 2 were printed via a StarFire® SG1024 recirculating printhead from FUJIFILM Dimatix. The StarFire (R) SG1024 recirculating print head generally only works with non-aqueous inks because the faceplate tends to "wet" when used with water-based inks, thus adversely affecting press performance. Used together.

  However, the ink of the example was printed without any problem. The print head was photographed using a JetXpert drop watcher. There was no evidence of wet faceplates with any of the inks of the present invention.

Wet clock fastness (wet crock-fastness)
Ink Examples 1 and 2 and Comparative Ink Examples 1 and 2 were printed on a polyolefin film.

The wet clock fastness of the prints was evaluated using the ASTM D5264 protocol revised in F1571.
The results are shown below. Larger numbers reflect higher wet clock fastness.

Clearly, the inks of the present invention show better wet clock fastness than the comparative inks.
To test the foam resistance of the foam test ink, 2 mL of ink was introduced into a disposable 12 cm plastic test tube. Thereafter, air was bubbled through the ink for 2 minutes to form a foam as it was. Thereafter, the ink was allowed to stand for 2 minutes to eliminate the foam as it was. Measurements of the height of the foam formed on the ink were recorded at 30 second intervals during foam generation and foam disappearance. The test was repeated three times. The average results are shown in the table below.

  Clearly, the inks of the present invention show a much lower tendency to foam than the comparative inks, and the foam formed disappears much more quickly.

Claims (15)

(A) 0.5 to 5 parts of a self-dispersing pigment;
(B) 2-8 parts styrene acrylic latex binder and / or styrene butadiene latex binder;
(C) 0.5-5 parts polyurethane latex binder;
(D) 0 to 5 parts glycol selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol or triethylene glycol;
(E) 1-10 parts 2-pyrrolidone;
(F) 1-15 parts glycerol;
(G) 0.1 to 3 parts of an acetylenic surfactant;
(H) 0.001 to 5 parts biocide;
(I) 0-10 parts of viscosity modifier; and (j) up to 100 parts of residual water;
Ink containing.   The self-dispersing pigment of component (a) is selected from the group consisting of carbon black; Pigment Blue 15: 3; Pigment Blue 60; Pigment Yellow 74; Pigment Yellow 155; Pigment Red 254 and Pigment Red 122. The ink described in 1.   The ink according to claim 1 or 2, wherein the self-dispersing pigment of component (a) comprises a carboxy functional dispersant that is crosslinked around the pigment core by two or more epoxy groups.   The ink according to any one of claims 1 to 3, wherein the component (b) is a styrene acrylic latex binder.   The ink according to any one of claims 1 to 4, wherein the component (c) is in the range of 1 to 3.0 parts.   The ink according to any one of claims 1 to 5, wherein the component (d) is ethylene glycol.   The ink according to any one of claims 1 to 6, wherein the component (e) is present in a range of 2.5 to 7.5 parts.   The ink according to any one of claims 1 to 7, wherein the component (f) is present in the range of 2 to 7.5 parts.   The ink according to any one of claims 1 to 8, wherein the component (g) is 2,4,7,9-tetramethyl-5-decyne-4,7-diol.   The ink according to any one of claims 1 to 9, wherein component (i) is polyethylene glycol. (A ′) 0.75 to 4 parts of a self-dispersing pigment;
(B ′) 4-10 parts styrene acrylic latex binder;
(C ′) 1-3 parts polyurethane latex binder (d ′) 0.5-2.5 parts ethylene glycol;
(E ') 2.5-7.5 parts 2-pyrrolidone;
(F ′) 2 to 7.5 parts of glycerol;
(G ′) 0.05 to 1.0 part 2,4,7,9-tetramethyl-5-decyne-4,7-diol;
(H ′) 0.001 to 2 parts biocide;
(I ′) 3-8 parts viscosity modifier;
(J ′) up to 100 parts of residual water;
The ink according to claim 1, comprising:   The ink-jet printing method which prints the ink as described in any one of Claims 1-11 on a base material using the ink-jet printer which has an ink recirculation type print head.   A substrate printed by the ink jet printing method according to claim 12.   The ink container for inkjet printers containing the ink defined in any one of Claims 1-11.   An inkjet printer comprising a recirculating printer head and an ink container for an inkjet printer containing ink according to claim 14.