JP4068028B2 - Emulsion ink jet ink composition - Google Patents

Description

  The present invention relates to an emulsion-type ink-jet ink composition, and more specifically, an emulsion that has excellent ejection stability while being quick-drying, can provide a clear and high-gloss printed matter, and has excellent fixability. Type ink-jet ink composition.

  In the field of inkjet inks, it is a very important research subject to achieve both the printing speed and the printing quality and to improve the ejection stability. The drying property of ink is known as a basic property that affects any of these performances.

  First, in order to improve the printing speed, it is indispensable to increase the drying speed of the ink. As the drying mode, there are two physical actions such as evaporation and penetration and chemical actions such as reaction and precipitation. It is considered. However, drying by chemical action is often difficult to control, and the apparatus and process are often complicated. Also, among the drying by physical action, if the drying by evaporation is accelerated, the ink dries while it is in the nozzle, and there is a high possibility that it will cause a decrease in ejection stability and a resulting decrease in print quality. Become.

  On the other hand, the drying by permeation occurs after the ink is printed on the printing medium, so that even if the drying speed is increased, the discharge stability is hardly lowered. Therefore, when printing on a permeable printed material such as paper, methods for positively promoting osmotic drying have been studied.

  For example, generally speaking, ink-jet ink refers to an aqueous type in which a dye is dissolved in water. However, since water has a high surface tension, penetration hardly occurs, and as it is, drying is slow. In view of this, a method has been used in which the surface tension of the system is lowered as much as possible by adding a water-miscible solvent, a surfactant, or the like, and the penetrability is improved.

  However, in this method, there is a problem that the dye is diffused with the penetration of the aqueous component, and the concentration is liable to decrease and blur. In addition, when the substrate to be printed is thin, the problem that the ink penetrates to the back surface and makes it look bad remains unsolved.

  More recently, in addition to such technical problems, fundamental disadvantages of dyes, that is, the long-term storage of printed matter due to poor light resistance, low water resistance against sweat, etc. Such a point has been pointed out, and there is a demand for pigment-type ink. However, if a dye that has made it possible to perform high-quality printing by virtue of excellent performance such as vivid color developability and good ejection stability is replaced with a pigment, a number of technical problems will occur.

  For example, since pigments do not dissolve in water or organic solvents, it is extremely difficult to restore normal conditions when clogging occurs due to ink concentration or solidification in the nozzle. Thus, the reliability of so-called ink-jet ink is lowered.

  In addition, in order to clearly develop an insoluble pigment, it is necessary to stably disperse it with finer particles. However, since the pigment basically has a hydrophobic surface, the dispersibility in an aqueous medium is It is at a low level. Furthermore, when dispersed in the form of particles, when the ink permeates into the printing medium, diffusion occurs vigorously, and it becomes difficult to maintain a high color density as a printed matter.

  As described above, in order to shift to the pigment-type water-based ink-jet ink, there are many problems in terms of ink reliability and printing quality.

  Therefore, as one means for solving the above-mentioned problem, an aqueous continuous phase (aqueous component in the present invention) containing water as a main component and a discontinuous non-aqueous phase (invention) in which a pigment is dispersed in a hydrophobic solvent. And an emulsion type ink-jet ink comprising at least one polymer emulsifier is disclosed in Patent Document 1 and the like.

  In such an emulsion type ink-jet ink system, it is considered that the aqueous phase and the non-aqueous phase are separated after printing, and each component permeates into the printing medium separately, but the pigment is contained in the non-aqueous phase. Therefore, even if a larger amount of the aqueous phase permeates, the pigment does not diffuse. Therefore, by increasing the permeability of the aqueous phase, the pigment can remain on the surface of the printing medium while being fast-drying, and a clearer printed image can be obtained without causing high-concentration.

Japanese Patent Laid-Open No. 10-46069

  In the form of an ink composed of an aqueous continuous phase and a non-continuous non-aqueous phase as described above, the form of the aqueous continuous phase and the non-continuous non-aqueous phase should be stably maintained before printing and separated more quickly after printing. Is the most basic performance.

  However, Patent Document 1 is characterized only by a polymer emulsifier used for emulsifying a non-continuous non-aqueous phase into an aqueous continuous phase, and any non-aqueous carrier is used for the non-aqueous phase component. However, those having a high polarity have a problem that separation from the aqueous phase is delayed, and it is difficult to obtain good drying properties. In addition, ink with insufficient fixability has a problem that if the amount remaining on the surface of the substrate to be printed increases, the printed surface may become dirty due to rubbing or the like, and even hands and clothes may be colored. It has not been. In addition, many non-aqueous carriers such as ketones and aromatic compounds, particularly butyl acetate as disclosed in the examples of Patent Document 1, are corrosive to liquid contact parts such as inkjet printer heads. There is also a problem of shortening the lifetime of the device.

  Accordingly, an object of the present invention is to obtain a printed matter having good discharge stability, quick drying, clear and high gloss in a pigment type inkjet ink having high light resistance and water resistance, An object of the present invention is to provide an emulsion ink-jet ink composition having excellent fixability.

  As described above, in the water-based inkjet ink in which the colorant is directly dissolved or dispersed in the aqueous component, for the purpose of improving the drying property, if the penetration rate into the printing medium is increased, the aqueous component is combined with the aqueous component. The colorant component also penetrates, causing bleeding and a decrease in density. Therefore, it is technically very difficult to improve both dryness and high-quality printing performance with such a type of water-based inkjet ink.

  Therefore, by using an emulsion-type inkjet ink in which an oily component containing a colorant is dispersed in the form of fine droplets in an aqueous component, the repulsive action of water and oil is utilized when landing on the surface of the printing medium. Thus, a method of separating an aqueous component and an oily component (colorant component) and permeating them separately is considered.

  Usually, since the surface of the printing medium is subjected to hydrophilic treatment, if the aqueous component is selectively permeated into the printing medium, the oily component including the colorant remains in the vicinity of the surface of the printing medium. Can be made. It is considered that the faster the separation rate of the aqueous component and the oily component, the more the amount of the colorant that remains on the surface of the printing material, and the drying by permeation can be promoted without causing bleeding or a decrease in concentration. In the present invention, based on such consideration, the oil component contains a large amount of a saturated hydrocarbon compound having a high degree of hydrophobicity, and the material has a higher water-oil resilience, thereby improving the separation rate. It is intended.

  However, it is difficult to stably disperse an oily component having high hydrophobicity in an aqueous component, and the tendency becomes more remarkable as the droplets of the oily component become finer. On the other hand, in order to use as an emulsion type ink-jet ink, it is necessary to disperse the droplets of the oil component very finely. Problems such as causing layer separation occur.

  Therefore, as a means for solving this problem, an oil component can be obtained by using a compound having a chain hydrocarbon group having 12 or more carbon atoms in the molecule and an acid value of 5 mgKOH / g or more as a surfactant. The present invention has been completed by succeeding in achieving a balance between the ability to stably emulsify and disperse water in an aqueous component and the resilience.

  That is, the present invention provides the following emulsion-type inkjet ink composition.

(1) An oil component containing a pigment, a pigment dispersant, and a hydrophobic organic solvent having a boiling point of 180 ° C. or higher as a saturated hydrocarbon solvent as a main component has a chain hydrocarbon group having 12 or more carbon atoms in the molecule. An emulsion-type inkjet ink composition obtained by emulsifying in an aqueous component mainly composed of water using at least one surfactant selected from the group of compounds having an acid value of 5 mgKOH / g or more and salts thereof The emulsion-type inkjet ink composition, wherein the content of the oil component is 50% by mass or less based on the total amount of the emulsion-type inkjet ink composition.

(2) The emulsion-type inkjet ink composition according to (1), wherein the main component of the saturated hydrocarbon solvent is liquid paraffin.

(3) The emulsion-type inkjet ink composition according to (1) or (2), wherein the oil component further contains vegetable oil as a hydrophobic organic solvent.

(4) The surfactant contains at least a radical polymerizable compound having an alkyl group having 12 or more carbon atoms and an unsaturated double bond and a radical polymerizable compound having an acid group and an unsaturated double bond. The emulsion-type inkjet ink composition according to any one of (1) to (3) above, which is a polymer surfactant obtained by polymerization of a monomer mixture.

(5) The surfactant is a salt of a higher fatty acid having 13 or more carbon atoms, a salt of a dibasic acid having an alkenyl group having 12 or more carbon atoms, or a sulfate of a higher alcohol having 12 or more carbon atoms. Salts, alkyl ether sulfate esters having an alkyl group having 12 or more carbon atoms, phosphate esters of higher alcohols having 12 or more carbon atoms, alkylbenzene sulfonates having an alkyl group having 12 or more carbon atoms The emulsion-type inkjet ink composition according to any one of (1) to (4) above, which is at least one surfactant selected from the group.

(6) The emulsion type inkjet ink composition according to any one of (1) to (5), wherein the oily component is dispersed in the aqueous component using a high-pressure emulsifier.

(7) The high-pressure emulsifier includes a high-pressure emulsifier including a linear orifice portion having no bending portion and a bending portion, and a hollow member connected to the orifice portion and having a diameter larger than the orifice diameter of the orifice portion. The emulsion type ink-jet ink composition as described in (6) above, using an emulsifier.

  The emulsion-type ink-jet ink composition of the present invention obtained based on the above consideration can maintain the oily component stably dispersed in the aqueous component until immediately before printing, and promptly after the printing, the oily component. Since the water-based components are separated from each other, it is possible to solve the problems that water pigment-type ink-jet inks have so far, have good storage stability and ejection stability, fast drying during printing, Furthermore, it is an emulsion-type inkjet ink composition that can obtain a clear and high-gloss printed matter.

  Hereinafter, the present invention will be described in more detail.

  The present invention is an emulsion-type inkjet ink composition obtained by dispersing an oily component containing a pigment, a pigment dispersant and a saturated hydrocarbon solvent in an aqueous component using a surfactant.

<Oil component>
The oil component in the emulsion-type inkjet ink composition of the present invention is obtained by dispersing a pigment in a hydrophobic organic solvent containing a saturated hydrocarbon solvent as a main component using a pigment dispersant.

  Here, as the pigment, various inorganic and organic pigments that can be used in general inkjet inks can be used. As particularly useful ones, C.I. I. Pigment Yellow 93, 95, 109, 110, 120, 128, 138, 139, 151, 154, 155, 173, 180, 185, 193, C.I. I. Pigment orange 34, 36, 43, 61, 63, 64, 71, C.I. I. Pigment red 122, 202, a solid solution of 122 and 202, C.I. I. Pigment blue 15, C.I. I. Pigment violet 19, 23, 33, C.I. I. Pigment green 7, 36, C.I. I. Pigment black 7 and the like.

  In the inkjet recording method, based on four colors of yellow, magenta, cyan, and black, recently, a color image using six colors including orange and green, and eight colors including light magenta and light blue. Etc. are formed. Of these pigments, those having good weather resistance are more preferable. Among the pigments described above, C.I. I. Pigment Yellow 138, 154, 180, 185, and magenta include C.I. I. Pigment red 122, 202, C.I. I. Pigment Violet 19 and Cyan include C.I. I. Pigment Blue 15 and black include C.I. I. Pigment Black 7, particularly acidic or neutral pigments, oranges include C.I. I. Pigment Orange 43, 64, 71 and Green include C.I. I. Pigment Green 7 and 36 are more preferable.

  If necessary, metal powders such as aluminum, gold, silver, and zinc, metal oxides such as titanium oxide and aluminum oxide, and metal salts such as calcium carbonate and barium sulfate can be used.

  The pigment content may be a necessary amount depending on the use in the emulsion type ink-jet ink composition of the present invention, but is generally 0.1 to 50% by mass with respect to the total amount of the emulsion type ink-jet ink composition. Degree. And when the pigment content decreases, the color density decreases. On the other hand, if it increases too much, printing becomes difficult from the viewpoint of ink viscosity and fluidity. The preferable content of the pigment is 0.5 to 30% by mass, more preferably about 1 to 20% by mass with respect to the total amount of the emulsion type ink jet ink composition. In general, an inorganic pigment has a higher density than an organic pigment, and if it is the same weight, the coloring power is lowered. Therefore, when an inorganic pigment is used, it is preferably contained in a larger mass ratio.

  Next, the hydrophobic organic solvent in which the pigment is dispersed is mainly composed of a saturated hydrocarbon solvent having a boiling point (boiling point under normal pressure, the same shall apply hereinafter) of 180 ° C. or higher, and other hydrophobic organic solvents. When used in combination, select an oily component that can be stably dispersed in the aqueous component described below at least in the presence of the surfactant described later and that can be separated from the aqueous component faster after printing. It is necessary.

  Examples of the saturated hydrocarbon solvent include normal paraffin, isoparaffin, cycloparaffin, and the like. In particular, it is preferable to use a saturated hydrocarbon solvent mainly containing liquid paraffin containing them in a balanced manner.

  Liquid paraffin is a mixture of three components, mainly normal paraffin, isoparaffin, and monocyclic cycloparaffin, obtained by highly purifying relatively light lubricating oil components by washing with sulfuric acid. Among them, those containing 20% by weight or more of monocyclic cycloparaffins are more preferable.

  Purified to a level that does not substantially contain UV-absorbing impurities, and according to the purpose of use, purity of liquid paraffin according to the Japanese Pharmacopoeia, purity of liquid paraffin according to food additive standards established in Japan Those that have passed at least one of the tests and the purity test of liquid paraffin in the cosmetic raw material standards are more suitable in terms of work and hygiene.

  The purity test and standard values of these three liquid paraffins are currently the latest and are based on the cosmetic raw material standards based on the 14th revised Japanese Pharmacopoeia, the 7th edition Food Addendum, and Ministry of Health and Welfare Notification No. 181. Examples of liquid paraffin that are listed and passed both tests include Moresco White P-40, Moresco White P-55 (manufactured by Matsumura Oil Research Co., Ltd.), liquid paraffin No. 40-S, liquid paraffin No. 55-S (above, manufactured by Chuo Kasei Co., Ltd.).

  Further, as isoparaffins, isodecane, isododecane, and commercially available isoparaffin mixtures such as Isopar E, Isopar G, Isopar H, Isopar L, Isopar M (all of which are manufactured by Exxon Chemical Co., Ltd.), Shellsol (shell Oil Sol), Saltol (Philips Petroleum), Vegasol (Mobil Petroleum), IP Solvent 2835 (Idemitsu Petrochemical), etc. Examples of the paraffinic solvent include a mixture containing cyclodecane, decalin, and a commercially available cycloparaffin, such as Exol D130 and D140 (both manufactured by Exxon Chemical Co., Ltd.).

  In this way, when liquid paraffin is the main component and other saturated hydrocarbon solvents are mixed appropriately according to the required performance of the ink, isoparaffin solvents such as Isopar and Exol, and cycloparaffin solvents are used alone. Compared to the use in the above, it is possible to produce an emulsion-type inkjet ink composition having a good performance balance such as printability and drying property. The content of liquid paraffin is preferably 70% by weight or more based on the total saturated hydrocarbon solvent.

  Among these saturated hydrocarbon solvents, those having a viscosity at 25 ° C. of 20 mPa · s or less are preferable from the viewpoint of obtaining a clear printed matter, and low viscosity saturated hydrocarbon solvents and high viscosity saturated carbonization. It can also be used by mixing with a hydrogen-based solvent and adjusting to the above-mentioned viscosity.

  In consideration of the balance between improvement in printing speed by evaporative drying and clogging of the nozzles, the boiling point of the saturated hydrocarbon solvent is preferably in the range of 180 to 360 ° C./760 mmHg, and the saturated hydrocarbon solvent In the case of using the mixture, it is desirable that most of the components are in the above boiling range.

  In order to improve the pigment dispersibility and ejection stability of the oil component, other hydrophobic organic solvents may be used in combination with the hydrophobic organic solvent mainly composed of the saturated hydrocarbon solvent having a boiling point of 180 ° C. or higher. Of these, the combined use of vegetable oils is preferred.

  Here, available vegetable oils include soybean oil, rapeseed oil, cottonseed oil, sunflower oil, mustard oil, sesame oil, corn oil and other semi-drying oils, olive oil, falling raw oil, camellia oil and other non-drying oils, linseed oil And dry oils such as safflower oil, and these vegetable oils can be used alone or in combination.

  In particular, from the viewpoint of properties, it is a semi-drying oil or non-drying oil with low polymerization due to oxidation, and among them, rapeseed oil, olive oil, and cheap soybean oil with lower viscosity are more preferable.

  In addition, other hydrophobic organic solvents that can be used in combination include ketone-based hydrophobic organic solvents and ester-based hydrophobic organic solvents. A highly polar organic solvent can be used as an aqueous component when dispersed as oil droplets in water. It is preferable to use an organic solvent with a low polarity as much as possible, since it is difficult to keep the drying property from being slow and it may be difficult to keep the wetted part of the ink jet printer corroded.

  The hydrophobic organic solvent in the present invention is mainly composed of a saturated hydrocarbon solvent having a boiling point of 180 ° C. or higher, and is used in combination with other hydrophobic organic solvents as necessary, but is saturated with a boiling point of 180 ° C. or higher. The hydrocarbon solvent is preferably used in the range of 100 to 50% by mass of the total hydrophobic organic solvent, and the saturated hydrocarbon solvent having a boiling point of 180 ° C. or higher is used in the range of 100 to 70% by mass of the total hydrophobic organic solvent. Is more preferable.

  Next, the pigment dispersant used for dispersing the pigment in the hydrophobic organic solvent is not particularly limited as long as the pigment can be stably dispersed in the hydrophobic organic solvent. Among them, a reaction product of a polyamine compound and 12-hydroxystearic acid self-condensate is preferable, and specifically, a reaction product of polyallylamine and 12-hydroxystearic acid self-condensation product; Reaction product of polyethylene polyamine and 12-hydroxystearic acid self-condensate, for example, as a commercial product, Solsperse 13940 (trade name, manufactured by Avicia Co., Ltd.), dialkylaminoalkylamine and 12-hydroxystearic acid self-condensate As a commercially available product, Solsperse 17000, 18000 (both trade names, Shea Co., Ltd.) and the like can be mentioned.

  Various polymer pigment dispersants that can be dissolved in the hydrophobic organic solvent of the oil component, such as acrylic resins and styrene-acrylic resins, can also be used.

  Furthermore, a polymer compound used as a polymer surfactant described later, which has a pigment dispersing function, a function of dispersing an oily component in an aqueous component, and a function of fixing to a printing medium after printing, can also be suitably used as a pigment dispersant. .

  The amount of the pigment dispersant used is usually about 5 to 200% by mass with respect to the pigment.

  As other oil component materials, pigment derivatives such as Solsperse 5000 (manufactured by Avicia Co., Ltd.), various surfactants, resolubility and fixability to a printing medium, etc., which are effective in dispersing pigments Petroleum resins and rosin-modified maleic acid resins that are effective for improvement, and polymer compounds used as polymer surfactants described later can also be used, and various additives such as viscosity modifiers can also be added.

  As a method for preparing the oil component composed of the above components, first, a pigment dispersant is dissolved in a hydrophobic organic solvent to form a dispersant solution, and further, a pigment, and a surfactant as necessary are stirred and mixed. A method of adding and mixing the remaining materials after kneading with a kneading machine can be used.

  Examples of the meat mill include a wet circulation mill, a bead mill, a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, an ultrahigh pressure homogenizer, and a pearl mill. In the inkjet ink, a wet circulation mill is preferable among the above-mentioned models because it is necessary to disperse the pigment more finely than a normal printing ink.

  The oil component obtained by dispersing the pigment in the hydrophobic organic solvent obtained by the above method has a viscosity of 1.0 to 30.0 mPa · s and a surface tension of 26 to 30 mN / m at the environmental temperature at the time of use. When the viscosity and the surface tension of the oil component are in this range, the dischargeability from the nozzle, the drying property, the cosmetics of the printed matter, etc. can be maintained well.

  In addition, the content of the oil component is an amount that is 50% by mass or less based on the total amount of the emulsion type ink-jet ink composition, and when the content exceeds the above, the oil component is dispersed when dispersed in the aqueous component as oil droplets. Stability is lowered, which is not preferable. In addition, there is no restriction | limiting in particular as a minimum of content of an oil-based component, However, When it becomes too low content, since a function required as an oil-based component cannot be performed, it is desirable to set it as 1 mass% or more.

<Surfactant>
The surfactant used to disperse the oily component of the present invention as droplets in an aqueous component to be described later includes an acid value of 5 mg KOH / g or more having a chain hydrocarbon group having 12 or more carbon atoms in the molecule. As long as these surfactants and salts thereof are used, either a high molecular surfactant which is a polymer or a low molecular weight surfactant (hereinafter referred to as a low molecular surfactant) can be used.

  Among them, as the polymer surfactant, a compound having an alkyl group having 12 or more carbon atoms in the molecule and a radical polymerizable unsaturated double bond, a carboxyl group, a sulfonic acid group, a phosphate group, etc. in the molecule It is obtained by copolymerizing a monomer component that contains an acid group and a compound having a radically polymerizable unsaturated double bond, and may optionally contain other compounds having a radically polymerizable unsaturated double bond. A polymeric surfactant is preferred.

  Here, as a compound having an alkyl group having 12 or more carbon atoms in the molecule and a radically polymerizable unsaturated double bond, alkyl having 12 or more carbon atoms such as lauryl (meth) acrylate and stearyl (meth) acrylate. Α-olefins having 14 or more carbon atoms such as (meth) acrylate compounds, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 1-docosene, 1-tetracocene, 1-octacosene, 1-triacontene Etc. The upper limit of the carbon number in the alkyl group having 12 or more carbon atoms is not particularly limited, but is usually about 30 carbon atoms.

  In addition, compounds having an acid group and a radically polymerizable unsaturated double bond in the molecule include (meth) acrylic acid, crotonic acid, maleic anhydride, maleic acid, monoalkyl ester compounds of maleic acid, itaconic acid, itaconic Carboxyl group-containing unsaturated monomers such as monoalkyl ester compounds of acids, citraconic acid, monoalkyl ester compounds of citraconic acid, 2-acrylamido-2-methyl-1-propanesulfonic acid, 2-methacrylamide-2-methyl -1-Sulfonic group-containing unsaturated monomers such as propanesulfonic acid and styrenesulfonic acid, and phosphoric acid group-containing unsaturated monomers such as acid phosphonyl (meth) acrylate and acid phosphonylethyl (meth) acrylate I can give you.

  Other compounds having a radically polymerizable unsaturated double bond include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, etc. Examples include compounds having an alkyl group having 11 or less carbon atoms and radically polymerizable unsaturated double bonds, styrene monomer compounds such as styrene, α-methylstyrene, vinyltoluene, and acrylamide monomer compounds. Can do.

  In the monomer component composed of the above compound, when the content of the compound having an alkyl group having 12 or more carbon atoms in the molecule and a radically polymerizable unsaturated double bond decreases, the oil component is dispersed in water. Since the dispersion stability at the time decreases, the content is preferably 5% by mass or more, and the upper limit is preferably about 60% by mass.

  In addition, when the content of the compound having an acid group and a radically polymerizable unsaturated double bond in the molecule is reduced, the dispersion stability when the oil component is dispersed in water is similarly reduced. It is necessary to make it contain in the quantity from which an acid value will be at least 5 mgKOH / g or more. On the other hand, when the polymer has a high acid value, separation of the oily component and the aqueous component may be difficult to occur, and therefore the upper limit of the acid value is preferably about 350 mgKOH / g. From the standpoint of compatibility between the dispersion stability and the drying property, the acid value of the polymer is more preferably 10 to 300 mgKOH / g, especially 30 to 250 mgKOH / g, which is a normal acid group-containing radical polymerizability. In terms of the content of the compound, it corresponds to about 3 to 40% by mass.

  Furthermore, when copolymerizing the above-mentioned other compounds having a radically polymerizable unsaturated double bond, the dispersibility and separation rate of the oily component in the aqueous component are determined according to the composition of the oily component and the aqueous component described later. Can be used together up to about 55% by mass, preferably 10 to 55% by mass.

  These polymer surfactants can be used in the range of mass average molecular weight of about 1,000 to 1,000,000, and also have good dispersion stability of the oil component and fixability when printed on a printing medium. The weight average molecular weight is more preferably in the range of 5,000 to 100,000 from the viewpoint that the emulsion type ink-jet ink composition can be maintained at a low viscosity.

  Examples of the low molecular surfactant having a chain hydrocarbon group having 12 or more carbon atoms in the molecule that can be used in the emulsion type ink-jet ink composition of the present invention and having an acid value of 5 mgKOH / g or more include 13 or more carbon atoms. Higher fatty acid salts, dibasic acid salts having an alkenyl group having 12 or more carbon atoms, sulfates of higher alcohols having 12 or more carbon atoms, alkyl having an alkyl group having 12 or more carbon atoms Examples thereof include ether sulfate esters, phosphate esters of higher alcohols having 12 or more carbon atoms, and alkylbenzene sulfonates having an alkyl group having 12 or more carbon atoms.

  Specifically, as salts of higher fatty acids having 13 or more carbon atoms, for example, salts of dibasic acids having an alkenyl group having 12 or more carbon atoms such as sodium stearate and sodium oleate, for example, succinic anhydride Examples of sulfate salts of higher alcohols having 12 or more carbon atoms, such as sodium salts and amine salts of the reaction product of oleyl alcohol with oleyl alcohol (succinic acid monoester), such as sodium lauryl alcohol sulfate, ammonium lauryl alcohol sulfate, cetyl alcohol Examples of the alkyl ether sulfate salts having an alkyl group having 12 or more carbon atoms such as sodium sulfate ester, sodium stearyl alcohol sulfate, sodium oleyl alcohol sulfate, etc. include lauryl ether sulfate ester. Examples of phosphate esters of higher alcohols having 12 or more carbon atoms such as tersodium include sodium lauryl alcohol phosphate (mono or di) ester (di or mono), stearyl alcohol phosphate (mono or di) ester (di or di) Examples of alkylbenzene sulfonates having an alkyl group having 12 or more carbon atoms, such as mono) sodium, oleyl alcohol phosphate (mono or di) ester (di or mono) sodium, can include sodium dodecylbenzenesulfonate and the like. .

  The above polymer or low molecular surfactant is preferably contained in water in an amount not less than the critical micelle concentration and further increased as the oil phase content increases. The content thereof is preferably about 1 to 100% by mass, particularly about 5 to 50% by mass with respect to the oil component.

  In the emulsion type ink-jet ink composition, if the oily component and aqueous component are separated immediately after printing and the dryness can be maintained, other surfactants can be added to improve the dispersibility of the oily component. It can be used together.

<Aqueous component>
Next, the water-based component used in the emulsion-type ink-jet ink composition of the present invention may be water alone, but if necessary, a basic compound that can be used for emulsifying the polymer surfactant or water. It may contain miscible organic solvents and other various additives.

  First, examples of usable basic compounds include inorganic basic compounds such as ammonium hydroxide, and organic basic compounds such as triethylamine, monoethanolamine, and triethanolamine. The amount of these basic compounds used is as follows. The amount of the polymeric surfactant is not limited as long as it stabilizes the micelle formation. Usually, an appropriate amount is about 80 to 120 mol% of the neutralized amount of the polymeric surfactant.

  Next, usable water-miscible organic solvents include lower alcohols such as methanol, ethanol and propanol, (poly) alkylene glycols such as (poly) ethylene glycol and (poly) propylene glycol, butoxyethoxyethanol ( Examples thereof include alkyl ethers of poly) alkylene glycol.

  Furthermore, various additives, such as a viscosity modifier and an antifoamer, can also be utilized.

<Method for Producing Emulsion Type Inkjet Ink Composition>
As a method for producing the emulsion-type inkjet ink composition of the present invention using the above materials, a method of dispersing an oily component in an aqueous component using various emulsifying means can be used.

  Among them, as an emulsifying means, after preparing a mixed liquid of an oily component, a surfactant and an aqueous component, it is allowed to pass through a nozzle-like path under high pressure, and the mixed liquid collides with the mixed liquid and the emulsifying device wall. A method of generating impact force due to impact of water or a shearing force due to a speed difference between mixed liquids, a method of generating cavitation in a mixed liquid, a method of colliding an aqueous component containing a surfactant and an oily component, etc. A high-pressure emulsification method comprising

  Specific examples of apparatuses that can be used in the above-described high-pressure emulsification method include Nirosoabi type high-pressure emulsifiers (manufactured by Nirosoavi), Nanomizer (manufactured by Nanomizer), Microfluidizer (manufactured by Microfluidics), and Ultimizer (Sugino Machine). And high pressure emulsifiers such as DeBEE2000 (BEE International).

  A particularly preferred high-pressure emulsifier is DeBEE2000. FIG. 1 shows a schematic cross-sectional view of the main part of this apparatus. As shown in FIG. 1, this apparatus includes a fluid pressurizing portion 1, a linear orifice portion 2 having no curved portion and a bent portion, and a hollow member 3 having a diameter larger than the orifice diameter of the orifice portion 2. It is an ultra-high speed emulsification device arranged in series. A hollow portion is formed in the hollow member 3 by connecting a plurality of substantially cylindrical cell members 4 via a seal 5.

  Then, as shown in the schematic cross-sectional view of FIG. 2, the liquid mixture 10 in which the oil component, the surfactant and the aqueous component used in the present invention are mixed in advance from the hopper 11 or the like using the pressure pump 12. The pressure is introduced into the pressurizing unit 1 and pressurized, and is passed through the linear orifice unit 2 having no curved and bent portions at high speed. Here, by adjusting the orifice diameter and the speed of passing through the orifice portion 2, it is possible to generate an optimum stress applied to the mixed solution in the orifice in order to obtain a uniform and fine dispersion.

  Further, a high-speed jet flow of the mixed liquid generated by passing through the orifice portion 2 is injected into the hollow member 3 to cause cavitation due to pressure drop or mixing that has been previously injected and stays in the hollow member 3. The oily component is dispersed in the aqueous component by a shear stress generated by a difference in speed from the liquid to obtain an oil-in-water emulsion type inkjet ink composition.

  The obtained emulsion-type inkjet ink composition 15 is discharged from the discharge port 13 and stored in the storage tank 16. In addition, it is also possible to control the flow rate of the mixture in the hollow member 3 by providing a back pressure valve 14 between the discharge port 13 and the pipe path of the storage tank 16 as shown in FIG. .

More specifically, normally, the orifice portion 2 of this apparatus has an orifice diameter of 0.01 to 1.5 mm. The mixture adjusted so that the viscosity is preferably 1 Pa · sec or less, more preferably 0.5 Pa · sec or less, and further preferably 0.2 Pa · sec or less is preferably 5 × 10 ^{3 to} 3.2 × 10 ⁵ kPa, Pressurizes to about 8 × 10 ^{4 to} 2 × 10 ⁵ kPa, and passes through the orifice portion 2 at a flow rate of preferably 100 to 1000 m / sec, more preferably 300 to 700 m / sec. Stress due to change is applied to the mixture.

  The hollow member 3 preferably has a cylindrical shape, and the ratio of the orifice diameter of the orifice portion 2 to the tube inner diameter of the hollow member 3 is set to 1: so that an appropriate speed difference occurs due to shear stress between the mixed liquids. (2 to 50), more preferably about 1: (5 to 10), and it is desirable that the high-speed jet flow has a sufficient volume so that it does not collide with the downstream end portion of the hollow member 3 with a strong force. Preferably, by controlling so that the velocity of collision with the downstream end portion of the hollow member 3 becomes substantially zero, a high shearing force is generated, and the oil component can be dispersed in finer droplets in the aqueous component.

  Further, as shown in the schematic cross-sectional view of FIG. 3, the liquid mixture passing through the orifice portion 2 and traveling through the hollow member 3 is reflected by the wall of the plug member 7 provided at the downstream end portion of the hollow member 3. It is also possible to use a method of reciprocating once and letting it flow out from the discharge port 17 provided in the vicinity of the orifice portion 2 side. In this case, a back pressure valve 18 can also be provided. In this method, the liquid mixture that first passes through the orifice portion 2 and is reflected by the wall of the plug member 7 and returns through the hollow member 3, and then passes through the orifice portion 2 and proceeds through the hollow member 3. When the mixed liquid is counter-flowed, the stress applied in the hollow member 3 becomes higher, and finer droplets of an oil component are obtained, which is advantageous as a method for producing an emulsion-type inkjet ink composition. Note that the mixed liquid reflected by the wall of the plug member 7 and returning through the hollow member 3 is also mixed in the recess 6 between the cell members 4.

  Furthermore, a path for introducing a fluid is provided separately from the orifice portion 2, and a method of causing an aqueous component containing a surfactant to collide with an oil component introduced from the other path as a high-speed jet flow by the above-described method is used. You can also.

  The emulsion type ink-jet ink composition of the present invention obtained from the above materials and production method has a viscosity of about 1.0 to 10 mPa · s at the ambient temperature during use.

  The emulsion-type ink-jet ink composition of the present invention has good ejection stability while being fast-drying, and has higher image quality at a higher speed when printed on paper, plastic film, etc. using various ink-jet printing devices. A printed matter can be obtained.

  Especially for glossy paper with high surface smoothness and permeability, a printed matter with high gloss and good fixability can be obtained, and for highly permeable plain paper, etc., a printed matter with a high concentration of hue can be obtained. The present invention has excellent effects not found in conventional pigment-type inkjet ink compositions.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. Unless otherwise specified, “parts” and “%” represent “parts by mass” and “% by mass”, respectively.

(1) Preparation of polymeric surfactant / Preparation of polymeric surfactant 1 32 parts by mass of acrylic acid, 30 parts by mass of stearyl methacrylate, and 38 parts by mass of styrene were copolymerized by a conventional method to obtain a mass average molecular weight of 8,000, Polymeric surfactant 1 (solid) having an acid value of 250 mgKOH / g was obtained.

-Preparation of polymer surfactant 2 Polymer interface having a mass average molecular weight of 10,000 and an acid value of 40 mgKOH / g by copolymerizing 5 parts by mass of acrylic acid, 55 parts by mass of methyl methacrylate, and 40 parts by mass of stearyl methacrylate. Activator 2 (solid) was obtained.

-Preparation of Polymer Surfactant 3 40 mass parts of acrylic acid, 10 mass parts of lauryl methacrylate, 30 mass parts of methyl methacrylate, and 20 mass parts of styrene were copolymerized by a conventional method to obtain a mass average molecular weight of 12,000 and an acid value of 317 mg KOH. / G polymer surfactant 3 (solid) was obtained.

-Preparation of polymer surfactant 4 A mass average molecular weight of 8,000 was obtained by copolymerizing 0.5 parts by mass of acrylic acid, 30 parts by mass of stearyl methacrylate, 40 parts by mass of methyl methacrylate, and 29.5 parts by mass of styrene by a conventional method. Polymeric surfactant 4 (solid) having an acid value of 4 mgKOH / g was obtained.

-Preparation of polymer surfactant 5 A polymer having a mass average molecular weight of 8,000 and an acid value of 250 mgKOH / g by copolymerizing 32 parts by mass of acrylic acid, 30 parts by mass of 2-ethylhexyl methacrylate and 38 parts by mass of styrene by a conventional method. Surfactant 5 (solid) was obtained.

(2) Preparation of oil component by pigment dispersion treatment / Oil component 1
Phthalocyanine pigment (5412SD, manufactured by Dainippon Ink & Chemicals, Inc.) 40 parts by mass, liquid paraffin (Moresco White P-40, manufactured by Matsumura Oil Research Co., Ltd.) 148 parts by mass, pigment dispersant (Solsperse 18000, Avicia 8 parts by weight (manufactured by Co., Ltd.) and 4 parts by mass of a dispersion aid (Solsperse 5000, manufactured by Avicia Co., Ltd.) were kneaded in a bead mill to obtain oil component 1. The viscosity of the oily component 1 at 25 ° C. was 28 mPa · s, and the surface tension at 25 ° C. was 27 mN / m. The viscosity was measured with a B-type viscometer, and the surface tension was measured with a dynamic wettability tester manufactured by Reska (hereinafter the same).

・ Oil component 2
To 100 parts by mass of oil component 1, 150 parts by mass of liquid paraffin (Molesco White P-40, manufactured by Matsumura Oil Research Co., Ltd.) was added and mixed to obtain oil component 2. The viscosity of the oily component 2 at 25 ° C. was 10 mPa · s, and the surface tension at 25 ° C. was 26 mN / m.

(3) Preparation of emulsion-type inkjet ink composition Example 1
After dissolving 6 parts by mass of the polymeric surfactant 1 in a triethanolamine aqueous solution composed of 3.1 parts by mass of triethanolamine and 75.9 parts by mass of water, 15 parts by mass of the oil component 1 is added, Stir and mix with a high-speed mixer. The obtained mixture is of the structure shown in FIG. 3, using a high-pressure emulsifier (DeBEE2000, manufactured by BEE International) with an orifice diameter of 0.15 mm and a hollow member tube diameter of 1 mm. The oil component was emulsified in water by passing it through the orifice under a pressure of × 10 ⁵ kPa at a flow rate of 600 m / sec and discharging it into the mixture that had flowed out and stayed in the hollow member (number of passes). 5 times). To this emulsion, 80 parts by weight of water, 15 parts by weight of glycerin, and 5 parts by weight of butoxyethoxyethanol were added and mixed to obtain the emulsion type inkjet ink composition of Example 1.

Example 2
The composition and production method of Example 2 were the same as in Example 1 except that 1.6 parts by mass of triethanolamine, 80.4 parts by mass of water, and 3 parts by mass of polymeric surfactant 1 were used. An emulsion type inkjet ink composition was obtained.

Example 3
The same composition and production method as in Example 1 except that triethanolamine was 4.7 parts by mass, water was 71.3 parts by mass, and polymer surfactant 1 was 9 parts by mass. An emulsion type inkjet ink composition was obtained.

Example 4
The same composition and production method as in Example 1 except that 0.5 parts by mass of triethanolamine and 78.5 parts by mass of water were used, and the total amount of the polymeric surfactant 1 was changed to the polymeric surfactant 2. Thus, an emulsion type ink-jet ink composition of Example 4 was obtained.

Example 5
The same composition and production method as in Example 1 except that 3.9 parts by mass of triethanolamine, 75.1 parts by mass of water, and the total amount of the polymeric surfactant 1 was changed to the polymeric surfactant 3 Thus, an emulsion type ink-jet ink composition of Example 5 was obtained.

Example 6
After mixing 6 parts by mass of an amine salt of a reaction product of succinic anhydride and oleyl alcohol in a triethanolamine aqueous solution consisting of 4 parts by mass of triethanolamine and 75 parts by mass of water, 15 parts by mass of oil component 1 is further added. Part was added and stirred and mixed with a high-speed mixer. The obtained mixture is of the structure shown in FIG. 3, using a high-pressure emulsifier (DeBEE2000, manufactured by BEE International) with an orifice diameter of 0.15 mm and a hollow member tube diameter of 1 mm. The oil component was emulsified in water by passing it through the orifice under a pressure of × 10 ⁵ kPa at a flow rate of 600 m / sec and discharging it into the mixture that had flowed out and stayed in the hollow member (number of passes). 5 times). To this emulsion, 80 parts by weight of water, 15 parts by weight of glycerin and 5 parts by weight of butoxyethoxyethanol were added and mixed to obtain an emulsion type ink jet ink composition of Example 6.

Example 7
In a triethanolamine aqueous solution composed of 2 parts by mass of triethanolamine and 71 parts by mass of water, 3 parts by mass of an amine salt of a reaction product of succinic anhydride and oleyl alcohol, 3 parts by mass of an adduct of 15 mol of ethylene oxide of oleyl alcohol After mixing the parts, 15 parts by mass of the oil component 1 was further added, and the mixture was stirred and mixed with a high speed mixer. The obtained mixture is of the structure shown in FIG. 3, using a high-pressure emulsifier (DeBEE2000, manufactured by BEE International) with an orifice diameter of 0.15 mm and a hollow member tube diameter of 1 mm. The oil component was emulsified in water by passing it through the orifice under a pressure of × 10 ⁵ kPa at a flow rate of 600 m / sec and discharging it into the mixture that had flowed out and stayed in the hollow member (number of passes). 5 times). To this emulsion, 80 parts by weight of water, 15 parts by weight of glycerin and 5 parts by weight of butoxyethoxyethanol were further added and mixed to obtain an emulsion type ink-jet ink composition of Example 7.

Example 8
After dissolving 15 parts by mass of Polymer Surfactant Preparation Example 1 in a triethanolamine aqueous solution consisting of 8 parts by mass of triethanolamine and 77 parts by mass of water, 75 parts by mass of oil component 2 was added, and a high-speed mixer was added. Stir and mix with. The obtained mixture is of the structure shown in FIG. 3, using a high-pressure emulsifier (DeBEE2000, manufactured by BEE International) with an orifice diameter of 0.15 mm and a hollow member tube diameter of 1 mm. The oil component was emulsified in water by passing it through the orifice under a pressure of × 10 ⁵ kPa at a flow rate of 600 m / sec and discharging it into the mixture that had flowed out and stayed in the hollow member (number of passes). 5 times). To this emulsion, 10 parts by weight of water, 15 parts by weight of glycerin and 5 parts by weight of butoxyethoxyethanol were added and mixed to obtain an emulsion type ink jet ink composition of Example 8.

Comparative Example 1
The same composition and production method as in Example 1 except that 0.1 parts by weight of triethanolamine and 75.9 parts by weight of water were used, and the whole amount of the polymer surfactant 1 was changed to the polymer surfactant 4. Thus, an emulsion type ink-jet ink composition of Comparative Example 1 was obtained.

Comparative Example 2
An emulsion-type inkjet ink composition of Comparative Example 2 was obtained using the same composition and production method as in Example 1 except that the total amount of the polymer surfactant 1 was changed to the polymer surfactant 5.

Comparative Example 3
A comparative example with the same composition and production method as in Example 7 except that the total amount of 3 parts by mass of the amine salt of the reaction product of succinic anhydride and oleyl alcohol was changed to an ethylene oxide 15 mol adduct of oleyl alcohol. 3 emulsion type ink-jet ink composition was obtained.

Comparative Example 4
After dissolving 16.5 parts by mass of polymeric surfactant 1 in a mixed solution consisting of 8.8 parts by mass of triethanolamine, 44.7 parts by mass of water, 15 parts by mass of glycerin, and 5 parts by mass of butoxyethoxyethanol. Then, 110 parts by mass of oily component 2 was added, and the mixture was stirred and mixed with a high-speed mixer. The obtained mixture is of the structure shown in FIG. 3, using a high-pressure emulsifier (DeBEE2000, manufactured by BEE International) with an orifice diameter of 0.15 mm and a hollow member tube diameter of 1 mm. Under pressure of 10 ⁵ kPa, pass through the orifice at a flow rate of 600 m / sec, discharge into the mixture that has flowed out and stay in the hollow member, and emulsify the oily component in the aqueous component. The emulsion type ink-jet ink composition of Example 4 was obtained (5 passes). This emulsion-type inkjet ink composition was not subjected to a later evaluation test because the oil component could not be well dispersed in the aqueous component.

  The emulsion type inkjet ink compositions of Examples 1 to 8 all had a viscosity at 25 ° C. in the range of 1.0 to 10 mP · s.

(4) Evaluation of Examples 1-8 and Comparative Examples 1-3 Emulsion Type Inkjet Ink Compositions (a) Emulsion Stability Evaluation Method for Oily Components Emulsion Type Inkjet Ink Compositions of Examples 1-8 and Comparative Examples 1-3 The product was put into a 50 ml glass bottle, sealed and stored at 40 ° C. for 10 days, and the presence or absence of separation between the oily component and the aqueous component was visually confirmed to evaluate the emulsion stability of the oily component. The results are shown in Table 1.
Evaluation criteria A: Separation of oily component and aqueous component is not recognized.
B: Separation of oily component and aqueous component is observed.

(B) Evaluation of ejection stability, drying on paper, gloss, fixing property, leveling property and color sharpness Emulsion ink jet inks of Examples 1 to 8 and Comparative Examples 1 to 3 using commercially available ink jet printers The ejection stability, the drying on paper, the gloss, the fixing property, the leveling property and the sharpness when the composition was printed were evaluated. The results are shown in Table 1. Inkjet printers, glossy paper and plain paper used the following.
Inkjet printer: PM-900C (manufactured by Seiko Epson Corporation)
Glossy paper: EPSON glossy paper (manufactured by Seiko Epson Corporation)
Plain paper: Xerox L (Fuji Xerox Office Supply Co., Ltd.)

The evaluation method and the criteria for determination are as follows.
-Ejection stability evaluation method The head was filled with the emulsion type ink-jet ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3, and the cap was not used for 3 days in an environment with a room temperature of 30 ° C and a relative humidity of 50%. The ejection stability from the orifice was evaluated according to the conditions under which printing was possible.
Evaluation criteria A: Printing can be performed without cleaning the discharge orifice. B: The discharge orifice needs to be cleaned one to four times before printing is possible. C: The discharge orifice needs to be cleaned five times or more before printing is possible.

Drying evaluation method After printing the emulsion type ink-jet ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3 on glossy paper and plain paper, respectively, and drying from the time until the ink adheres to the finger due to finger touch Sex was evaluated.
Evaluation criteria A: Drying within 1 second.
B: Drying within 5 seconds over 1 second.
C: What does not dry even if it exceeds 5 seconds.

Gloss evaluation method The emulsion type ink-jet ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3 were respectively printed on glossy paper, and the gloss of the printed matter was measured with a gloss meter: Micro Gloss 60 (manufactured by Big Chemie Japan Co., Ltd.). The value was measured.
Evaluation criteria A: Gloss value of 50 or more.
B: Gloss value of 20 or more and less than 50.
C: Gloss value less than 20.

Fixability evaluation method The emulsion type ink-jet ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3 were printed on glossy paper, naturally dried for 60 minutes, and then the print surface was rubbed with the same glossy paper. The fixability was evaluated from the presence or absence of smudges of the ink.
Evaluation criteria A: Ink does not adhere at all.
B: The ink slightly adheres and is lightly colored.
C: The ink adheres and is deeply colored.

Leveling property evaluation method Printing was performed using the emulsion type ink-jet ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3 so as to obtain a printed material having a gradation of 100% to 20% on glossy paper. Graininess was visually judged from the continuity, and the leveling property of the printed matter was evaluated.
Evaluation criteria A: Gradation is continuously observed in the entire area.
B: Lines that are less than 80% can be seen.
C: Those with lines that are less than 100%.

Color vividness evaluation method Printing was performed using the emulsion type ink-jet ink compositions of Examples 1 to 8 and Comparative Examples 1 to 3 so as to form a solid print on plain paper, and the appearance was visually determined. .
Evaluation criteria A: A thing with no dullness and very good appearance.
B: Slightly dull, but looks good.
C: There is a lot of dullness and it doesn't look good.
D: A dullness that feels sunk as printed matter.

It is a schematic sectional drawing which shows the principal part of the high-pressure emulsifier used suitably when manufacturing the emulsion type inkjet ink composition of this invention. It is a schematic sectional drawing which shows one Example of the high pressure emulsifier used suitably when manufacturing the emulsion type inkjet ink composition of this invention. It is a schematic sectional drawing which shows the other Example of the high-pressure emulsifier used suitably when manufacturing the emulsion type inkjet ink composition of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressurization part 2 Orifice part 3 Hollow member 10 Liquid mixture 15 Emulsion type inkjet ink composition

Claims (7)

An oil component containing a pigment, a pigment dispersant, and a hydrophobic organic solvent having a saturated hydrocarbon solvent having a boiling point of 180 ° C. or higher as a main component, an acid value of 5 mg KOH having a chain hydrocarbon group having 12 or more carbon atoms in the molecule / Emulsion type ink-jet ink composition obtained by emulsifying in an aqueous component containing water as a main component, using at least one surfactant selected from the group of compounds and salts thereof, The emulsion-type inkjet ink composition, wherein the content of the oil component is 50% by mass or less based on the total amount of the emulsion-type inkjet ink composition. The emulsion-type inkjet ink composition according to claim 1, wherein the main component of the saturated hydrocarbon solvent is liquid paraffin. The emulsion-type inkjet ink composition according to claim 1 or 2, wherein the oil component further contains vegetable oil as a hydrophobic organic solvent. Monomer mixture in which the surfactant contains at least a radical polymerizable compound having an alkyl group having 12 or more carbon atoms and an unsaturated double bond, and a radical polymerizable compound having an acid group and an unsaturated double bond The emulsion type ink-jet ink composition according to any one of claims 1 to 3, which is a polymer surfactant obtained by polymerization. The surfactant is a salt of a higher fatty acid having 13 or more carbon atoms, a salt of a dibasic acid having an alkenyl group having 12 or more carbon atoms, a sulfate ester salt of a higher alcohol having 12 or more carbon atoms, carbon Selected from the group of alkyl ether sulfates having an alkyl group having 12 or more, phosphate esters of higher alcohols having 12 or more carbons, and alkylbenzene sulfonates having an alkyl group having 12 or more carbons The emulsion type ink-jet ink composition according to any one of claims 1 to 4, which is at least one surfactant. The emulsion-type inkjet ink composition according to any one of claims 1 to 5, wherein the oil component is dispersed in the aqueous component using a high-pressure emulsifier. As the high-pressure emulsifier, a high-pressure emulsifier comprising a linear orifice portion having no curved portion and a bent portion, and a hollow member connected to the orifice portion and having a diameter larger than the orifice diameter of the orifice portion. The emulsion-type inkjet ink composition according to claim 6, wherein the emulsion-type inkjet ink composition is used.

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