JP2008303301A - Method for producing color material, and method for producing ink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve storage stability of ink by preventing agglomeration of a hydrophobic colloid by impurities. <P>SOLUTION: The ink is produced by mixing, to a solvent, a dye of at least magenta or black, a hydrophobic colloid the zeta potential of which is positively charged in a pH range of between 4 and 6, and either one or both of copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate; heating the mixture to agglomerate impurities contained in the hydrophobic colloid and the dye, and the copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate; removing the agglomerate; and removing impurities from the die. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a color material contained in ink and a method for manufacturing ink, which are used in a printer device that prints an image by discharging ink from fine discharge ports.

  In a printer apparatus (inkjet printer apparatus) using an inkjet recording method, for example, yellow, magenta, cyan, and black inks are ejected from fine nozzles to print a color image. In such an ink jet printer apparatus, an ink discharge head in which nozzles are formed is moved in the width direction of the recording paper, and a serial type printer apparatus that performs printing for one row, and the nozzles are arranged in the width direction of the recording paper. An ink discharge head provided with a nozzle line formed and ejecting ink for each nozzle line for one column at a time without moving the ink discharge head in the width direction of the recording paper. There is a line-type printer apparatus that performs printing. The line type printer device does not need to move the ink discharge head in the width direction of the recording paper unlike the serial type printer device, and the ink is discharged for each nozzle line of yellow, magenta, cyan, and black. The time can be greatly shortened.

  As a line-type printer device, for example, there is one shown in Patent Document 1 below. The printer device described in Patent Document 1 ejects ink from a head chip provided on the ejection surface of the ink ejection head, and the ink supplied to the liquid chamber of the head chip is disposed in the liquid chamber. It is pressed by the heat generating resistor and discharged from a nozzle formed at a position facing the heat generating resistor.

  In such a printer device, since the ejection characteristics when ejecting ink from the nozzles of the head chip greatly affect the image quality, it is possible to increase the processing accuracy. For example, a head in which a heating resistor is built in a silicon wafer A chip is used.

  The head chip forms a heating resistor on the silicon wafer, and the end surface of the silicon wafer constitutes a part of a flow path for supplying ink to the liquid chamber. In the head chip, the surface of the silicon wafer on which the heating resistor is formed is subjected to oxidation treatment or the like. For example, silicon or silicon oxide does not elute into the ink even when exposed to ink. In the manufacturing process, it is difficult to perform an oxidation process or the like on the end surface on the flow path side, and the silicon wafer is exposed. Therefore, when this end surface is exposed to ink, silicon, silicon oxide, or the like is contained in the ink. May elute. In particular, the elution of silicon and silicon oxide from the silicon wafer becomes remarkable when the pH is higher than 7 so as not to oxidize the metal member constituting the ink discharge head among the inks.

  In such a head chip, due to the dissolution of the silicon wafer, the dimensional accuracy of the head chip is lowered, the ink ejection characteristics are deteriorated, and there is a problem that the quality of the printed image is deteriorated or the ink is not ejected.

  In order to solve this problem, the ink in contact with the end face of the silicon wafer contains a hydrophobic colloid whose zeta potential is positively charged when the pH is in the range of 4 to 6. In the head chip, since the ink contains a hydrophobic colloid that has a zeta potential positively charged when the pH is in the range of 4 or more and 6 or less, the ink comes into contact with the end surface of the silicon wafer, and from the end surface. When silicon or silicon oxide elutes and the pH of the ink around the edge of the silicon wafer is in the range of 4 to 6, the negatively charged hydrophobic colloid is positively charged on the edge of the silicon wafer. It adheres and suppresses further elution of silicon and silicon oxide from the silicon wafer.

  However, in such a head chip, by incorporating a hydrophobic colloid in the ink, it is possible to prevent silicon and the like from eluting from the silicon wafer, while the impurities contained in the ink cause hydrophobicity. The colloidal agglomerates, and as time passes, the particle size of the generated aggregates increases, clogging the flow path, ink is not supplied from the flow path to the liquid chamber, nozzle clogging occurs, and from the nozzle Ink is not properly ejected, and ejection characteristics deteriorate. In addition, the aggregation of the hydrophobic colloid does not progress during the ink adjustment, and since the size of the aggregate is small, it cannot be removed even through a filter immediately after the ink adjustment. Then, after the ink is adjusted, when the head chip is filled, the size of the aggregate increases and cannot be removed from the head chip. In particular, among the inks, magenta and black inks tend to cause aggregation of hydrophobic colloids and easily cause problems.

JP 2004-244620 A

  The present invention has been proposed in view of such conventional circumstances, and removes impurities in magenta and black dyes to prevent aggregation of hydrophobic colloids due to the impurities, and storage stability of ink. It is an object of the present invention to provide a method for producing a color material and an ink production method that make the ink excellent.

  The method for producing a coloring material according to the present invention comprises: a solvent having at least a magenta or black dye; a hydrophobic colloid in which a zeta potential is positively charged when the pH is in the range of 4 to 6, and copper phthalocyanine Mixing and heating one or both of sulfonic acid and copper phthalocyanine sulfonate, impurities contained in the dye in the hydrophobic colloid and one or both of copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate And a colorant is produced by removing the aggregate obtained by aggregating the hydrophobic colloid.

  The ink production method according to the present invention includes at least a magenta or black dye as a solvent, a hydrophobic colloid whose zeta potential is positively charged when the pH is in the range of 4 to 6, and copper phthalocyanine sulfone. Mix one or both of acid and copper phthalocyanine sulfonate, and heat to mix impurities contained in the dye in the hydrophobic colloid and one or both of copper phthalocyanine sulfonate and copper phthalocyanine sulfonate. The ink is produced by removing the aggregated aggregate.

  In the method for producing a coloring material according to the present invention, magenta and black dyes, a hydrophobic colloid in which the zeta potential is positively charged when the pH is in the range of 4 to 6, copper phthalocyanine sulfonic acid, copper By mixing either or both of the phthalocyanine sulfonates, impurities are adsorbed on the hydrophobic colloid together with copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate, and the hydrophobic colloid aggregates. Thereby, in this color material manufacturing method, the impurities are aggregated into the hydrophobic colloid, and the color material containing the dye from which the impurities are removed can be obtained by removing the aggregate containing the generated impurities.

  In the method for producing an ink according to the present invention, in a solvent, at least a magenta or black dye, a hydrophobic colloid in which a zeta potential is positively charged when a pH is in a range of 4 or more and 6 or less, By mixing one or both of copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate, impurities are adsorbed on the hydrophobic colloid together with copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate, and the hydrophobic colloid aggregates. Aggregates containing the produced impurities are removed. Thereby, in this ink manufacturing method, impurities in the dye are aggregated and removed by the hydrophobic colloid, so that further aggregation of the hydrophobic colloid due to the impurities can be prevented, and time passes after adjustment of the ink. In addition, an ink excellent in storage stability in which the formation of aggregates is prevented can be obtained. Also, in this ink manufacturing method, after removing the aggregates, the remaining hydrophobic colloid does not aggregate, so the remaining hydrophobic colloid adheres to the end surface of the head chip where the silicon-containing material is exposed. And it can prevent that silicon and a silicon compound elute from this end face.

  Hereinafter, a color material manufacturing method and an ink manufacturing method to which the present invention is applied will be described. The color material obtained by the color material manufacturing method to which the present invention is applied is used, for example, as an ink for an ink jet printer apparatus that prints a color image by ejecting ink onto a recording paper in the form of fine droplets. It is done. In an ink jet printer, for example, in addition to two colors of magenta ink and black ink, four colors of ink including yellow ink and cyan ink are used.

  First, prior to the description of the magenta ink and the black ink obtained by the color material manufacturing method and the ink manufacturing method to which the present invention is applied, an ink jet printer apparatus (hereinafter referred to as a printer apparatus) in which these inks are used. .).

  As shown in FIGS. 1 and 2, the printer device 1 includes an inkjet printer head cartridge (hereinafter referred to as a head cartridge) 3 that ejects ink 2 to be described later onto, for example, a recording paper P that is an object, and And an apparatus main body 4 to which the head cartridge 3 is mounted. This printer apparatus 1 is a so-called line type printer apparatus in which one or more nozzles 32a for ejecting ink are arranged in a line substantially in the width direction of the recording paper P, that is, the arrow W direction in FIG. In the printer apparatus 1, the head cartridge 3 can be attached to and detached from the apparatus main body 4.

  First, the head cartridge 3 constituting the printer apparatus 1 will be described. The head cartridge 3 ejects the ink 2 by a heating resistor 31a using an electrothermal conversion type as a pressure generating element, for example, and landes the ink 2 on the main surface of the recording paper P. As shown in FIGS. 1 and 2, the head cartridge 3 is mounted with an ink cartridge 11 containing the ink 2. The ink cartridge 11 includes a yellow ink cartridge 11y, a magenta ink cartridge 11m, a cyan ink cartridge 11c, and a black ink cartridge 11k for each color. The ink cartridge 11 is formed in a substantially rectangular shape having substantially the same dimension as the dimension in the width direction of the recording paper P. As shown in FIG. 2, the ink cartridge 11 includes an ink supply unit 12 for supplying the ink 2 to the cartridge main body 21 of the head cartridge 3. The ink cartridge 11 may be formed integrally with the head cartridge 3.

  The head cartridge 3 to which the ink cartridge 11 is mounted has a cartridge body 21 as shown in FIGS. The cartridge body 21 includes a mounting portion 22 to which the ink cartridge 11 is mounted, an ink discharge head 23 that discharges the ink 2, and a head cap 24 that protects the ink discharge head 23.

  A connection portion connected to each ink supply unit 12 corresponding to the ink supply unit 12 of each of the ink cartridges 11y, 11m, 11c, and 11k mounted on the mounting unit 22 is provided at the approximate center in the longitudinal direction of the mounting unit 22. 25 is provided. The connection unit 25 supplies ink 2 to the ink discharge head 23 that discharges the ink 2 provided on the bottom surface of the cartridge body 21 from the ink supply unit 12 of the ink cartridges 11y, 11m, 11c, and 11k mounted to the mounting unit 22. The ink supply path is supplied. The connection unit 25 adjusts the supply of the ink 2 from the ink cartridges 11y, 11m, 11c, and 11k to the ink discharge head 23 by a valve mechanism.

  The ink discharge head 23 to which the ink 2 is supplied from the connection unit 25 is provided on the bottom surface of the cartridge main body 21. In the ink discharge head 23, nozzles 32a, which are discharge ports for discharging the ink 2 supplied from the connecting portion 25, are arranged in parallel for each color in a substantially line shape in the width direction of the recording paper P, that is, the arrow W direction in FIG. ing. In the ink discharge head 23, among a plurality of nozzles 32a arranged in parallel in the width direction of the recording paper P, head chips 26, each having a predetermined number, are arranged in a substantially staggered manner across the width direction of the recording paper P. Thus, the nozzle 32a is formed in a substantially line shape. The ink discharge head 23 discharges the ink 2 from the head chips 26 arranged in a substantially line shape without moving in the width direction of the recording paper P when discharging the ink 2.

  As shown in FIG. 3, the head chip 26 includes a circuit board 31 provided with an electrothermal change type heating resistor 31 a, a nozzle sheet 32 on which a nozzle 32 a is formed, and the circuit board 31 and the nozzle sheet 32. It is formed with a film 33 provided therebetween. In the head chip 26, an ink liquid chamber 34 surrounded by a circuit board 31, a nozzle sheet 32, and a film 33 is formed. The ink liquid chamber 34 is filled with the ink 2 heated by the heating resistor 31a. The ink discharge head 23 is formed with an ink flow path 35 for supplying the ink 2 from the ink cartridge 11 containing the ink 2 to the ink liquid chamber 34.

  The circuit board 31 is formed with a control circuit made up of a logic IC (Integrated Circuit), a driver transistor, etc. on a board made of a silicon-containing material such as a silicon wafer or a glass substrate. The circuit board 31 is provided with a heating resistor 31 a that is controlled by a control circuit and heats the ink 2 as a pressure generating element. The surface on which the heating resistor 31a of the circuit board 31 is provided is covered with a silicon thermal oxide film because it is easy to oxidize in the assembly process, and silicon-containing materials such as a silicon wafer and a glass substrate are exposed. Ink 2 is not in direct contact with the silicon-containing material. On the other hand, since the end surface 31b on the ink flow path 35 side of the circuit board 31 cannot be oxidized in the assembly process, a silicon-containing material such as a silicon wafer or a glass substrate is exposed, and the ink 2 is exposed to the silicon-containing material. Be in direct contact.

  The nozzle sheet 32 is formed with a nozzle 32a having a reduced diameter toward the ejection surface 23a, and is disposed to face the circuit board 31 and the film 33 so as to form a lower surface portion of the ink liquid chamber 34. ing.

  The film 33 is made of, for example, an exposure-curing type dry film resist, and is formed so as to surround each nozzle 32a except for the portion communicating with the ink flow path 35 described above. Further, the film 33 is interposed between the circuit board 31 and the nozzle sheet 32, thereby forming a side surface of the ink liquid chamber 34.

  The ink ejection head 23 in which the head chips 26 configured as described above are arranged in parallel in the width direction (W direction) of the recording paper P is a circuit of the head chip 26 of the color to be ejected by a recording signal based on the print data. The control circuit of the substrate 31 is controlled to supply a pulse current to the selected heating resistor 31a to heat the heating resistor 31a. In the ink discharge head 23, when the heating resistor 31a is heated, as shown in FIG. 3A, bubbles b are generated in the ink 2 in contact with the heating resistor 31a. In the ink discharge head 23, as shown in FIG. 3B, the ink 2 is pressurized while the bubbles b expand, and the pushed ink 2 is discharged from the nozzle 32a in the form of droplets. Further, in the ink discharge head 23, after discharging the ink 2, the ink 2 is supplied to the ink liquid chamber 34 through the ink flow path 35, thereby returning to the state before the discharge again. The ink discharge head 23 repeats the above-described operation according to the recording signal based on the print data, and discharges the ink 2 of each color onto the recording paper P to print a color image.

  As shown in FIG. 1, a head cap 24 for protecting the ejection surface 23a on which the nozzles 32a are formed is attached to the ejection surface 23a side of the ink ejection head 23. The head cap 24 does not eject the ink 2 and blocks the ejection surface 23a of the ink ejection head 23 to protect the nozzle 32a from drying and the like while printing is not performed. When performing printing, the head cap 24 moves from the bottom surface of the head cartridge 3 to the front surface side of the apparatus main body 4 as shown in FIG. 4 to expose the ejection surface 23a of the ink ejection head 23 to the outside. As shown in FIG. 4, the head cap 24 is provided with a cleaning roller 24a for wiping off excess ink adhering to the ejection surface 23a. When opening or closing the ejection surface 23a, the head cap 24 cleans the ejection surface 23a with the cleaning roller 24a, and removes excess ink 2 attached to the ejection surface 23a.

  As shown in FIG. 1, the head cartridge 3 is mounted on the head cartridge mounting portion 41 in the apparatus main body 4 to which the head cartridge 3 having such a configuration is mounted. Further, the apparatus main body 4 is attached with a paper feed tray 42 in which recording paper P before printing is stacked and stored on the lower front side, and a paper discharge tray for storing the recording paper P after printing on the upper front side. 43 is attached.

  As shown in FIG. 4, the apparatus main body 4 is provided with a paper supply / discharge mechanism 44 for conveying the recording paper P and a head cap opening / closing mechanism for opening / closing a head cap 24 (not shown).

  With the configuration described above, the printer apparatus 1 supplies current to be supplied to the paper supply / discharge mechanism 44, the head cap opening / closing mechanism, and the ink ejection head 23 based on print data input from an information processing apparatus provided outside. A control unit provided with a control circuit that controls the supply and discharge of the recording paper P, the opening and closing of the head cap 24, and the supply of current to the ink ejection head 23 are controlled.

  Specifically, in the printer apparatus 1, first, when an instruction to start printing is given to the control unit by operating the operation button 4a provided on the apparatus body 4 shown in FIG. The mechanism 44 and the head cap opening / closing mechanism are driven, and printing is possible as shown in FIG.

  In the printer apparatus 1, the head cap 24 is moved with respect to the head cartridge 3 to the front side of the apparatus main body 4 provided with the paper feed tray 42 and the paper discharge tray 43 by the head cap opening / closing mechanism. As a result, the printer device 1 can eject the ink 2 by exposing the nozzles 32a provided on the ejection surface 23a of the ink ejection head 23 to the outside.

  Further, the printer apparatus 1 pulls out only one sheet of recording paper P from the paper feed tray 42 by a paper feed / discharge mechanism 44 including a plurality of transport rollers 45. Then, the printer apparatus 1 conveys the recording paper P to the conveyance belt 46 provided at a position facing the ejection surface 23 a of the ink ejection head 23 by the paper supply / discharge mechanism 44. In the printer apparatus 1, the recording paper P is opposed to the ejection surface 23a by supporting the recording paper P conveyed by the conveyance belt 46 with a platen 47 at a position facing the ejection surface 23a.

  Next, the printer apparatus 1 supplies a drive current to the heating resistor 31a selected by the control signal based on the print data among the plurality of heating resistors 31a provided in the ink ejection head 23, and the selected heating is performed. The resistor 31a is heated. As shown in FIG. 4, the printer device 1 heats the heating resistor 31a to make the ink 2 in a droplet state from the nozzle 32a on the recording paper P conveyed to a position facing the ejection surface 23a. To discharge and print a color image.

  Next, the printer apparatus 1 includes the recording paper P on which the printing of the recording paper P is completed by the conveyance belt 46 that rotates the recording paper P in the direction of the paper discharge tray 43 and the paper discharge roller 48 provided to face the conveyance belt 46. Is sent to the paper discharge tray 43, and the printed recording paper P is discharged to the paper discharge tray 43. In this way, the printer apparatus 1 prints an image on the recording paper P. After printing, the head cap 24 waiting on the front side of the apparatus main body 4 is moved by the head cap opening / closing mechanism to move the bottom surface of the head cartridge 3 to block and protect the ejection surface 23a of the ink ejection head 23.

  In such a printer device 1, the pH of the ink 2 is 4 in the ink 2 so that silicon and silicon compounds do not elute from the end face 31 b of the circuit board 31 constituting the head chip 26 where the silicon-containing material is exposed. As described above, the zeta potential is positively charged when it is in the range of 6 or less, and the hydrophobic colloid that adheres to the negatively charged end surface 31b of the circuit board 31 is contained. Ink 2 is used so that no elution occurs. In the printer apparatus 1, yellow ink 2, magenta ink 2, cyan ink 2, and black ink 2 are used. Among these four color inks 2, magenta ink 2 and black ink 2 are included in ink 2. When a hydrophobic colloid is contained in the mixture, impurities in the dye and the hydrophobic colloid are aggregated to easily generate aggregates. Therefore, the dye is manufactured using the dye from which the impurities are removed.

  The magenta ink 2 and the black ink 2 can be manufactured as follows. Since both the magenta ink 2 and the black ink 2 can be manufactured by the same manufacturing method, the manufacturing method of the magenta ink 2 will be described below, and the manufacturing method of the black ink 2 will be described in detail. The detailed explanation is omitted.

  The magenta ink 2 is produced by removing impurities from the dye to produce a coloring material mainly composed of the dye, and elution of silicon and silicon compounds from the obtained coloring material and the end face 31b of the circuit board 31. A magenta ink 2 is produced by mixing and filtering a hydrophobic colloid whose zeta potential is positively charged when the pH to be prevented is in the range of 4 or more and 6 or less.

  First, the method for producing a color material from which impurities have been removed is such that the zeta potential is positive when the pH for adsorbing magenta dye and the impurity in the dye is in the range of 4 to 6 in the color material solvent. Stir while heating a mixed solution of hydrophobic colloid charged with copper phthalocyanine sulfonic acid, copper phthalocyanine sulfonate, or both, and impurities contained in the dye, hydrophobic colloid and copper phthalocyanine Either or both of sulfonic acid and copper phthalocyanine sulfonate are aggregated, and the generated aggregate is removed by filtration to produce a coloring material mainly composed of a dye from which impurities are removed.

  In addition to solvents such as water and ion-exchanged water, the coloring material solvent used for producing the magenta coloring material is, for example, an aliphatic monohydric alcohol, an aliphatic polyhydric alcohol, an aliphatic polyhydric alcohol derivative, or the like. A water-soluble organic solvent is used.

  Examples of the aliphatic monohydric alcohol include lower alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, s-butyl alcohol, and t-butyl alcohol. Any one or a plurality of these may be used in combination.

  Examples of the aliphatic polyhydric alcohol include alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butylene glycol and glycerol, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, and thiodiglycol. Any one of these or a mixture of two or more of them may be used.

  Examples of the aliphatic polyhydric alcohol derivatives include lower alkyl ethers of the above-described aliphatic polyhydric alcohols such as ethylene glycol dimethyl ether, and lower carboxylic acid esters of the above-mentioned aliphatic polyhydric alcohols such as ethylene glycol diacetate. Used.

  Examples of the colorant solvent include aliphatic monohydric alcohols, aliphatic polyhydric alcohols and derivatives thereof, amides such as dimethylformamide and dimethylacetamide, ketones such as acetone and diacetone alcohol, and keto. Trivalent alcohols such as alcohols, tetrahydrofuran, dioxane, γ-butyllactone, glycerin, 1.2.6-hexanetriol, diethanolamine, triethanolamine, sulfolane, 2-pyrrolidone, N-methyl-2-pyrrolidone, 1 One or more of nitrogen-containing heterocyclic compounds such as 3-dimethyl-2-imidazolidinone may be mixed and added.

  Examples of magenta dyes include C.I. I. Acid Red 1, 6, 8, 9, 13, 14, 18, 26, 27, 32, 35, 37, 42, 51, 52, 57, 75, 77, 80, 82, 85, 87, 88, 89, 92, 94, 97, 106, 111, 114, 115, 117, 118, 119, 129, 130, 131, 133, 134, 138, 143, 145, 154, 155, 158, 168, 180, 183, 184, 186 194, 198, 209, 209, 211, 215, 219, 249, 252, 254, 262, 265, 274, 282, 289, 303, 317, 320, 321 and 322, C.I. I. Direct Red 1, 2, 2, 4, 9, 13, 17, 20, 23, 24, 28, 31, 31, 33, 37, 39, 44, the same 46, 62, 63, 75, 79, 80, 81, 83, 84, 89, 95, 99, 113, 197, 201, 218, 220, 224, 225, 226, 227, 228, 229, 230, 321, C.I. I. Reactive Red 1, 2, 3, 4, 4, 6, 7, 8, 11, 11, 12, 13, 16, 17, 17, 19, 20, 21, 21, 23, 24, 28, 29, 31, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41 42, 43, 45, 46, 49, 50, 58, 59, 63, 64, Food Red 7, 9, 14 and the like.

  The content of the magenta dye is 0.5 to 15% by weight, preferably 0.7 to 10% by weight.

  The hydrophobic colloid is positively charged with a zeta potential when the pH of a solution in which a dye, copper phthalocyanine sulfonic acid, copper phthalocyanine sulfonate, or the like is added to a colorant solvent is in the range of 4 to 6. Is. This hydrophobic colloid adsorbs impurities in the dye and copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate and aggregates them. Examples of such hydrophobic colloids include metal oxides such as aluminum oxide and cerium oxide, metal sulfides such as barium sulfate, and the like, or a mixture of one or more of these. . The content of the hydrophobic colloid is 0.25% by weight or more and 0.5% by weight or less with respect to the dye. By setting the content of the hydrophobic colloid to 0.25 wt% or more and 0.5 wt% or less with respect to the dye, impurities in the dye can be sufficiently adsorbed.

  Copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate improve the adsorptivity of impurities to the hydrophobic colloid and promote aggregation of the hydrophobic colloid. Content of this copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate is 5 ppm or more and 1000 ppm or less with respect to the dye 100. By making these contents 5 ppm or more and 1000 ppm or less, the obtained colorant does not have the color of copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate, and does not affect the color of magenta. Aggregation can be promoted.

  In the production method for producing a magenta color material, first, a magenta dye, a hydrophobic colloid, and one or both of copper phthalocyanine sulfonate and copper phthalocyanine sulfonate are mixed in a color material solvent. The solution is stirred with a screw or the like while being heated to 20 ° C to 60 ° C. Thereby, impurities in the dye are adsorbed on the hydrophobic colloid together with copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate, and the hydrophobic colloid aggregates. In this case, since the solution contains copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate, aggregation of the hydrophobic colloid is promoted.

  Next, the aggregate is removed from the solution. As a removal method, for example, a filter or a centrifuge is used. When separating using a filter, for example, a 0.1 μm filter is used.

  Next, the dye is filtered or centrifuged from the solution from which the aggregates have been removed to obtain a coloring material mainly composed of the dye. In addition to the magenta dye, the obtained magenta coloring material contains copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate which remain without being aggregated in the hydrophobic colloid, but the remaining copper Phthalocyanine sulfonic acid and copper phthalocyanine sulfonate do not affect magenta color.

  In the method for producing a magenta coloring material as described above, a dye, a hydrophobic colloid, and one or both of copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate are mixed, and impurities in the dye are copper phthalocyanine. Impurities can be removed from the dye by adsorbing to a hydrophobic colloid together with sulfonic acid or copper phthalocyanine sulfonate, aggregating the hydrophobic colloid, and removing the resulting aggregate from the solution. As a result, in the method for producing a magenta color material, a color material mainly composed of a magenta dye from which impurities are removed can be obtained.

  Next, magenta ink 2 is manufactured as follows using the magenta color material from which impurities are removed. In the method for producing magenta ink 2, the pH for preventing the elution of silicon and silicon compounds from the end face 31b of the circuit board 31 and the color material from which impurities were removed in the ink solvent was in the range of 4 to 6. It is sometimes produced by including a hydrophobic colloid whose zeta potential is positively charged.

  As the ink solvent, ion-exchanged water, a water-soluble organic solvent, or the like can be used in the same manner as the color material solvent used in the color material manufacturing method described above. When aliphatic monohydric alcohol is used as the solvent for the ink, the surface tension of the ink 2 can be appropriately adjusted, and the ink has excellent permeability to the recording paper P and the like, dot formability, and drying of the printed image. 2 can be obtained. Further, when ethyl alcohol, i-propyl alcohol, n-butyl alcohol or the like is used among the aliphatic monohydric alcohols, more excellent penetrability, dot formability and the like can be obtained. In addition, when the aliphatic polyhydric alcohol and derivatives thereof are used, the ink 2 is difficult to dry, and the freezing point of the ink 2 can be lowered. Therefore, the change in physical properties when the ink 2 is stored for a long time is suppressed and the ink 2 is dried. It is possible to suppress the nozzle 32a from being clogged with the ink 2. Therefore, as a solvent for dispersing dyes, hydrophobic colloids, etc., in addition to water, etc., aliphatic monohydric alcohols, aliphatic polyhydric alcohols, derivatives of aliphatic polyhydric alcohols, etc. each having specific properties By using one kind or a mixture of plural kinds, it is possible to obtain the ink 2 suitable for the purpose and application.

  The content of the magenta color material is 0.5% by weight to 15% by weight, preferably 0.7% by weight to 10% by weight, based on the entire ink 2. The type of the recording paper P and the ejection method To determine the dye concentration. Ink 2, the lower the dye concentration, the better the viscosity adjustment and reliability when stored for a long time.

  In the hydrophobic colloid in which the zeta potential is positively charged when the pH is in the range of 4 or more and 6 or less, the ink 2 is applied to the end surface 31b of the circuit board 31 constituting the head chip 26 where the silicon-containing material is exposed. The zeta potential is positively charged and negatively charged when silicon or a silicon compound is eluted and the pH of the ink 2 in the vicinity of the end face 31b is in an acidic range from pH 4 to pH 6 from an alkaline state. It adheres to the end surface 31b of the circuit board 31 and suppresses further the elution of silicon and silicon compounds from the end surface 31b. Examples of such hydrophobic colloids include metal oxides such as aluminum oxide and cerium oxide, metal sulfides such as barium sulfate, and the like, as in the above-described method for producing a color material. One kind or a mixture of plural kinds is used.

  The content of the hydrophobic colloid is 3 ppm or more with respect to the entire ink 2. The content of the hydrophobic colloid is in the range of 3 ppm to 10000 ppm, more preferably in the range of 10 ppm to 1000 ppm. If it is less than 3 ppm, it will not be possible to sufficiently prevent elution of silicon or silicon compounds from the end face 31b of the circuit board 31.

  In addition to the colorant and the predetermined hydrophobic colloid, for example, a viscosity adjusting agent, a surface tension adjusting agent, a pH adjusting agent, an antiseptic, an antifungal agent and the like can be added to the ink 2.

  In addition to the color material and the hydrophobic colloid, the ink 2 may contain a surfactant as a dispersion aid for adjusting the surface tension and dispersing the color material substantially uniformly. As the surfactant contained in the ink 2, for example, a nonionic surfactant is preferable, but an anionic surfactant or the like can also be used.

  Nonionic surfactants include, for example, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl amines, polyoxyethylene alkyl amides, and acetylenes. Examples thereof include glycol-based surfactants, and any one or a combination of these may be used.

  Further, the ink 2 may contain a viscosity adjusting agent, a surface tension adjusting agent, a pH adjusting agent, a preservative, a fungicide, and the like as appropriate.

  Examples of viscosity modifiers and surface tension modifiers include proteins such as gelatin and casein, natural rubbers such as gum arabic, cellulose derivatives such as methylcellulose and carboxymethylcellulose, natural polymers such as lignin sulfonate and shellac, and polyallylates. , Styrene-acrylic acid copolymer salt, polyvinyl alcohol, polyvinyl pyrrolidone and the like, and any one or a combination of these may be used.

  Examples of the pH adjusting agent include alkali metal hydroxides or amines such as lithium hydroxide, sodium hydroxide, potassium hydroxide, triethanolamine, diethanolamine, and aminomethylpropanol.

  Examples of antiseptics and fungicides include sodium benzoate, sodium pentachlorophenol, sodium 2-pyridinethiol-1-oxide, sodium sorbate, sodium dehydroacetate, and 1,2-dibenzothiazoline-3- ON (product name: Proxel CRL, Proxel BND, Proxel GXL, Proxel XL-2, Proxel TN) and the like, and any one or a combination of these may be used.

  The magenta ink 2 having the above-described configuration can be manufactured as follows. First, a solution obtained by mixing a coloring material, a hydrophobic colloid whose zeta potential is positively charged when the pH is in the range of 4 or more, and a surfactant or the like in an ink solvent is 40 ° C. to 40 ° C. Stir with a screw or the like while heating to 80 ° C.

  Next, the solution is filtered through a 1.2 μm filter to remove dust and the like from the solution, and magenta ink 2 is obtained.

  Since the obtained ink 2 uses a coloring material containing a dye from which impurities have been removed, aggregation of the hydrophobic colloid due to impurities in the dye can be prevented. Even when the head chip 26 is filled, no agglomerates are generated and the storage stability is excellent. Further, in this ink 2, since the hydrophobic colloid does not aggregate, it is possible to prevent the hydrophobic colloid from adhering to the end surface 31b of the circuit board 31 and elution of silicon and silicon compounds from the end surface 31b.

  The black ink 2 can be produced by the same production method as the magenta ink 2, and impurities are removed from the black dye, and a color material mainly composed of the dye from which the impurities are removed is obtained. The obtained coloring material can be mixed with a hydrophobic colloid for preventing elution of silicon and silicon compounds from the end surface 31b of the circuit board 31 in an ink solvent. The black ink 2 also prevents aggregation of the hydrophobic colloid added during the production of the ink 2, and therefore, like the magenta ink 2, it has excellent storage stability, and silicon and silicon can be removed from the end surface 31 b of the circuit board 31. The elution of the silicon compound can also be prevented.

  Examples of the dye used when producing the black ink 2 include C.I. I. Acid Black 1, 2, 2, 7, 26, 29, 31, 31, 48, 50, 51, 52, 58, 60, 62, 63, 64, 67, 72, 76, 77, 94, 107, 108, 109, 110, 112, 115, 118, 119, 121, 122, 131, 132, 139, 140, 155, 156, 157, 158, 159, 191; I. Direct Black 17, 19, 22, 32, 38, 51, 56, 62, 71, 74, 75, 77, 94, 105, 106, 107, 108, 112, 113, 117, 118, 132, 133, 146, 154, 168, C.I. I. Reactive Black 1, 3, 3, 4, 5, 8, 9, 10, 10, 12, 13, 14, 18, C.I. I. Food black 2 etc. are mentioned.

  In the above, the magenta ink 2 was prepared in advance by removing impurities from the magenta dye and adding a colorant mainly composed of the dye from which the impurities were removed to the ink solvent. As shown below, a dye in the ink solvent, a hydrophobic colloid in which the zeta potential is positively charged when the pH is in the range of 4 to 6, and copper phthalocyanine sulfonate or copper phthalocyanine sulfonate Either one or both of them, impurities, copper phthalocyanine sulfonic acid, copper phthalocyanine sulfonate are adsorbed on the hydrophobic colloid in the ink solvent, and the aggregate formed by aggregation of the hydrophobic colloid is used as the ink solvent. By removing from the inside, the magenta ink 2 may be manufactured with the dye from which impurities are removed. When the ink 2 is manufactured by this manufacturing method, the hydrophobic colloid to be contained adsorbs impurities in the dye, and silicon and silicon compounds do not elute from the end surface 31b of the circuit board 31 constituting the head chip 26 described above. In order to adhere to the end face 31b as described above, a large amount is added in anticipation of the amount that is removed by adsorbing impurities. Further, the ink 2 is generally made weakly alkaline so that the portion of the ink discharge head 23 using the metal material or the like is not oxidized.

  In this magenta ink 2 production method, the ink solvent, magenta dye, hydrophobic colloid, copper phthalocyanine sulfonic acid, and copper phthalocyanine sulfonate are the same as those used in the magenta ink 2 production method described above. Things can be used. The contents of the dye, copper phthalocyanine sulfonic acid, and copper phthalocyanine sulfonate are the same as in the method for producing the magenta ink 2 described above.

  The method for producing the magenta ink 2 is as follows. First, a dye, a hydrophobic colloid whose zeta potential is positively charged when the pH is in the range of 4 to 6, and copper phthalocyanine sulfonic acid Then, a solution obtained by mixing one or both of copper phthalocyanine sulfonate and a surfactant or the like is stirred with a screw or the like while being heated to 40 ° C to 80 ° C. Note that the content of the hydrophobic colloid is increased in consideration of the amount of the impurities in the dye adsorbed and removed by the aggregate. In a solution in which a dye, a hydrophobic colloid, or the like is mixed, impurities in the dye are adsorbed on the hydrophobic colloid together with copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate, and the hydrophobic colloid is aggregated to form an aggregate.

  Next, the solution in which the aggregates are generated is filtered through a 3 μm filter, and aggregates and dust are removed from the solution to obtain magenta ink 2.

  The obtained ink 2 adsorbs impurities in the dye and copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate to the hydrophobic colloid, and agglomerates formed by aggregating a part of the hydrophobic colloid are filtered through a filter. To remove impurities from the dye. Thereby, in this ink 2, since the impurities are not contained in the dye, the remaining hydrophobic colloid does not agglomerate in order to prevent the silicon or silicon compound from eluting from the end face 31b of the circuit board 31. Even after the adjustment and for some time after the adjustment, even when the above-described head chip 26 is filled, the generation of aggregates can be prevented and the storage stability is excellent. Further, in this ink 2, since the remaining hydrophobic colloid does not aggregate, it is possible to prevent the hydrophobic colloid from adhering to the end surface 31b of the circuit board 31 and elution of silicon or silicon compounds from the end surface 31b. .

  Also, the black ink 2 can be produced by this production method in the same manner as the magenta ink 2, and impurities are removed from the black dye in the ink solvent, and a part of the hydrophobic colloid is aggregated. By removing the generated aggregates, it is possible to prevent aggregation of the remaining hydrophobic colloid and to prevent the generation of aggregates. As a result, in the black ink 2, the generation of aggregates is prevented, and similarly to the magenta ink 2, the storage stability is excellent, and the elution of silicon and silicon compounds from the end surface 31 b of the circuit board 31 can also be prevented. .

  In addition to the magenta ink 2 and the black ink 2 described above, the yellow ink 2 and the cyan ink 2 are described in, for example, Japanese Patent Application Laid-Open No. 2004-244620 using the following yellow and cyan dyes. In order to prevent elution of silicon and silicon compounds from the end surface 31b of the circuit board 31, like the yellow ink and cyan ink, the zeta potential is positive when the pH is in the range of 4 to 6 In which a hydrophobic colloid charged is used. In addition, in the cyan ink 2, even when a hydrophobic colloid is contained, aggregation of the hydrophobic colloid starts at the adjustment stage of the ink 2 due to copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate contained as a dye. Promotes and the agglomerates become larger, so that the agglomerates can be removed during the final filtration with a filter. In addition, in the yellow ink 2, when the ink 2 is added with copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate, the color of copper phthalocyanine sulfonic acid or copper phthalocyanine sulfonate is easily obtained. It is not preferable to add a sulfonate.

  Examples of yellow dyes include C.I. I. Acid Yellow 1, 3, 11, 17, 19, 23, 25, 29, 36, 38, 40, 42, 44, 49, 59, 61, 70, 72, 75, 76, 78, 79, 98, 99, 110, 111, 127, 131, 135, 142, 162, 164, 165, C. I. Direct Yellow 1, 8, 11, 11, 24, 26, 27, 33, 39, 44, 50, 58, 85, 86, 87, 88, 89, 98, 110, 132, 142, 144, C.I. I. Reactive Yellow 1, 2, 3, 4, 6, 7, 11, 12, 13, 14, 15, 15, 16, 17, 18, 22, 23, 24, 25, 26, 27, 37, 42, C.I. I. Food Yellow 3, 4 and the like can be mentioned, and any one or a combination of these can be used.

  Examples of cyan dyes include C.I. I. Acid Blue 1, 7, 9, 15, 22, 23, 25, 27, 29, 40, 41, 43, 45, 54, 59, 60, 62, 72, 74, 78, 80, 82, 83, 90, 92, 93, 100, 102, 103, 104, 112, 113, 117, 120, 126, 127, 129, 130, 131, 138, 140, 142, 143, 151, 154, 158, 161, 166, 167, 168 170, 171, 182, 183, 183, 184, 187, 192, 199, 203, 204, 205, 229, 234, 236, 249, C.I. I. Direct Blue 1, 2, 6, 15, 25, 41, 71, 76, 77, 78, 80, 86, 87, 90, 98, the same 106, 108, 120, 123, 158, 160, 163, 165, 168, 192, 193, 194, 195, 196, 199, 200, 201, 202, 203, 207, 225, 226, 236, 237, 246, 248, 249, C.I. I. Reactive Blue 1, 2, 2, 3, 4, 7, 7, 9, 13, 13, 15, 15, 17, 18, 19, 20, 20, 21 25, 26, 27, 28, 29, 31, 32, 33, 34, 37, 38, 39, 40, 41, 43, 44, 46 , C.I. I. Food Blue 1, 2 and the like can be mentioned, and any one or a combination of these can be used.

  In addition, the yellow ink 2 and the cyan ink 2 can use pigments in addition to the dye. In the case of using a pigment, a hydrophobic colloid that does not affect the zeta potential of silicon or a silicon compound is used to prevent elution of silicon or a silicon compound from the end surface 31b of the circuit board 31 of the head chip 26.

  When adjusting the ink 2 using a pigment, conventionally used fine pigment dispersion methods such as ball mill, sand mill, attritor, roll mill, agitator, Henshur mixer, colloid mill, ultrasonic homogenizer, pearl mill, Using a dispersing device such as a wet jet mill, the pigment is, for example, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, sodium hydrogen carbonate, ammonia water, trietamine amine, diethanolamine, triethylamine, aminomethylpropanol, etc. It can be prepared by dispersing the above-mentioned predetermined hydrophobic colloid or the like together in alkaline water.

  In the printer apparatus 1, as described above, in the magenta ink 2 and the black ink 2 obtained by the manufacturing method to which the present invention is applied, aggregation of hydrophobic colloids is prevented, and silicon and silicon are separated from the end face 31 b of the circuit board 31. The silicon compound is also prevented from being eluted, and the yellow ink 2 and the black ink 2 used in the yellow ink 2 and the black ink 2 are used as the end face of the circuit board 31 by using the yellow ink and the black ink described in JP-A-2004-244620. Since the elution of silicon and silicon compounds from 31b is prevented, the deformation of the circuit board 31 is prevented in the head chips 26 of each color, and the aggregates of the hydrophobic colloids clog the nozzles 32a and the ink flow paths 35. It is also possible to prevent clogging. Thereby, in the printer apparatus 1, it is possible to prevent the non-ejection of the ink 2 and the deterioration of the ejection characteristics, and it is possible to print a high-quality color image without white spots.

  Hereinafter, the ink prepared as a sample will be described. In the following, unless otherwise specified, the unit is% by weight. The present invention is not limited to these examples.

<Sample 1>
In Sample 1, 10% by weight of hexylene glycol as an ink solvent, 5% by weight of glycerol, and 0.3% by weight of Surfynol 465 (acetylene glycol; manufactured by Air Products, acetylene surfactant) as a surfactant. C. as a dye I. 3% by weight of Acid Red 52, C.I. as copper phthalocyanine sulfonate I. Acid Blue 199 0.1% by weight, aluminum oxide 0.1% by weight as a hydrophobic colloid, and Proxel GXL (1,2-dibenzothiazolin-3-one, manufactured by Avicia) as a fungicide 0.5% by weight %, And magenta ink was prepared by mixing them so that the remaining amount was purified water.

<Sample 2>
In sample 2, C.I. of copper phthalocyanine sulfonate was obtained. I. An ink was prepared in the same manner as Sample 1 except that the ink was adjusted without adding Acid Blue 199.

<Sample 3>
In sample 3, C.I. as copper phthalocyanine sulfonate was used. I. An ink was prepared in the same manner as Sample 1, except that acid blue 199 and aluminum oxide as a hydrophobic colloid were not added.

  The ink immediately after preparation of each sample produced as described above was filtered with a 3 μm filter. When the filter paper was observed, only sample 1 showed a cyan precipitate due to copper phthalocyanine sulfonate. As a result, it can be seen that impurities in the dye are adsorbed on the hydrophobic colloid together with the copper phthalocyanine sulfonate, and the agglomerates remain on the filter without passing through the filter due to aggregation of the hydrophobic colloid.

  For each ink, the number of particles (aggregate number) of 5 μm or more was measured after filtration with a 3 μm filter and after the ink was put in a sealed container and stored for 7 days in an environment of 60 ° C. The measuring method was measured with a particle counter KL-11A manufactured by Rion Corporation. The measurement results are shown in Table 1 below.

  In Sample 1, C.I. as aluminum oxide and copper phthalocyanine sulfonate as hydrophobic colloids. I. Since Acid Blue 199 is added, the impurities in the dye are C.I. I. Along with Acid Blue 199, it was adsorbed on aluminum oxide, which is a hydrophobic colloid, and an aggregate of aluminum oxide was grown. This aggregate was filtered through a 3 μm filter, and the aggregate was removed from the ink. Thereby, in Sample 1, impurities in the dye were removed from the ink. In such a sample 1, since impurities are removed from the dye, the number of particles (aggregate number) of 5 μm or more is small even immediately after filtration and after storage at 60 ° C. for 7 days. There was almost no change in the number of particles (the number of aggregates). Therefore, aluminum oxide and copper phthalocyanine sulfonate as C.I. I. It can be seen that inclusion of Acid Blue 199 can prevent the formation of aggregates immediately after filtration and during storage.

  On the other hand, in sample 2, since only the hydrophobic colloidal aluminum oxide is added and copper phthalocyanine sulfonate is not added, the adsorption of impurities in the dye to the hydrophobic colloidal aluminum oxide is not promoted, and the oxidation is performed. Since the aggregate of aluminum is small and cannot be removed by a filter, the aggregate is not removed from the ink. Thus, in Sample 2, when stored at 60 ° C. for 7 days, aluminum oxide aggregates grew, and the number of particles having 5 μm or more (the number of aggregates) was 7000, and the number of particles (the number of aggregates) was remarkably increased. From this sample 2, it can be seen that when copper phthalocyanine sulfonate is not contained, generation of aggregates cannot be prevented.

  In Sample 3, since aluminum oxide as a hydrophobic colloid was not contained, the generation of aggregates was suppressed even immediately after filtration and after storage at 60 ° C. for 7 days. However, since sample 3 does not contain a hydrophobic colloid, elution of silicon or a silicon compound cannot be prevented from the end face of the circuit board of the head chip provided in the printer apparatus described above.

It is a disassembled perspective view of the printer apparatus in which the ink to which this invention is applied is used. FIG. 3 is a cross-sectional view of the same head cartridge. FIG. 2A shows an ink discharge head. FIG. 1A is a cross-sectional view schematically showing a state where bubbles are generated on a heating resistor, and FIG. 1B schematically shows a state where ink is discharged from a nozzle. FIG. FIG. 6 is a perspective side view for explaining a printing operation of the printer apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Printer apparatus, 2 ink, 3 head cartridge, 4 apparatus main body, 11 ink cartridge, 21 cartridge main body, 23 ink discharge head, 26 head cap, 26 head chip, 31 circuit board, 31a heating resistor, 31b end surface, 32 nozzle Sheet, 32a nozzle, 33 film, 34 ink liquid chamber, 35 ink flow path

Claims (5)

  The solvent is at least a magenta or black dye, a hydrophobic colloid in which the zeta potential is positively charged when the pH is in the range of 4 to 6, and any of copper phthalocyanine sulfonate and copper phthalocyanine sulfonate. One or both are mixed and heated to adsorb impurities contained in the dye and one or both of the copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate to the hydrophobic colloid, and the hydrophobic colloid A method for producing a color material, wherein the color material is produced by removing aggregates obtained by agglomerating particles.   2. The method for producing a color material according to claim 1, wherein the content of the copper phthalocyanine sulfonic acid and the copper phthalocyanine sulfonate is such that the color of the magenta or black is not affected.   The solvent is at least a magenta or black dye, a hydrophobic colloid in which the zeta potential is positively charged when the pH is in the range of 4 to 6, and any of copper phthalocyanine sulfonate and copper phthalocyanine sulfonate. One or both are mixed and heated to adsorb impurities contained in the dye and one or both of the copper phthalocyanine sulfonic acid and copper phthalocyanine sulfonate to the hydrophobic colloid, and the hydrophobic colloid An ink production method comprising producing an ink by removing aggregates obtained by agglomerating particles.   4. The method for producing an ink according to claim 3, wherein the content of the copper phthalocyanine sulfonic acid and the copper phthalocyanine sulfonate is such that the color of the magenta or black is not affected.   4. The ink production method according to claim 3, wherein the content of the hydrophobic colloid is 3 ppm or more.

Images