JP2007277286A - Inkjet ink and ink tank containing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink which is excellent in the recording aptitude on a sheet of plain paper and particularly excellent in the jetting stability after being left for a short time, and an ink tank containing the ink. <P>SOLUTION: The inkjet ink comprises at least a coloring material, water, a water-soluble organic solvent and a surfactant, wherein the surfactant comprises a compound represented by general formula (I) and a compound represented by general formula (II) with a content ratio ((I)/(II)) in the ink of the compounds represented by general formulae (I) and (II), respectively, being within the range from at least 1/1 to at most 10/1 in terms of mass and the total content of these compounds in the ink being at least 0.2 mass%. The ink tank contains the ink. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water-based ink technology, and more particularly, to an ink technology excellent in printability on plain paper and ejection stability after being left for a short time. In particular, the present invention relates to an ink that can be suitably used in ink jet recording in which recording is performed on a recording medium by discharging from an orifice according to a recording signal, and an ink tank containing the ink.

  2. Description of the Related Art An inkjet recording type recording apparatus (inkjet recording apparatus) performs recording by ejecting ink from an inkjet recording head to a recording medium as recording means. The apparatus can easily make the recording means compact, can record high-definition images at high speed, can record on plain paper without requiring special processing, has low running cost, and is non-smoking. Since it is an impact method, there is an advantage that noise is low. Further, in addition to these advantages, there is an advantage that it is easy to record a color image using various types of ink (for example, color ink).

  Up to now, many improvements have been made to inkjet recording apparatuses that implement the above method, focusing on the ability to record on plain paper, such as copy paper, report paper, notebooks, stationery, bond paper, and continuous slip paper, which are widely used in general. It is coming. This is because it is considered to be used as an output device such as a personal computer, a copy machine, and a fax machine widely used in homes and offices.

For example, ink jet inks containing at least one acetylene alcohol or acetylene glycol have been proposed for the purpose of improving the fixability of ink on plain paper and improving print quality (for example, see Patent Document 1). The surface tension and viscosity at 25 ° C. are 26 × 10 ⁻⁵ N / cm or more and 40 × 10 ⁻⁵ N / cm or less, 0.7 × 10 ⁻³ mPa · s or more and 12 × 10 ⁻³ mPa · s or less, respectively. And an ink having an advancing contact angle with respect to the recording medium at 25 ° C. in the range of 60 ° to 180 ° is disclosed, and by using such an ink, the fixing property and bleeding resistance are high even on plain paper. It has been proposed to enable recording with excellent properties (see Patent Document 2). As described above, various proposals have been made to improve the suitability for recording on plain paper by adjusting the surface tension of the ink and the contact angle with the recording medium using an additive such as a surfactant.

  Furthermore, Patent Document 3 proposes an ink that has excellent penetrability and antifoaming property by adding two or more different surfactants. On the other hand, with the spread of digital cameras in recent years, ink jet recording apparatuses have been attracting attention as output devices for photographic images, and there is a growing demand for high-definition printed matter without graininess. In response to this demand, development of a recording head capable of stably ejecting smaller droplets is in progress. That is, by ejecting the ink in a smaller and more stable manner, it is possible to form minute dots uniformly on the recording medium, and a high-definition printed matter without graininess can be obtained.

  As a method for ejecting ink (droplets) that enables recording as described above, there is disclosed a method (hereinafter referred to as “atmospheric communication method”) in which recording is performed by communicating bubbles formed by thermal energy with the atmosphere. (For example, see Patent Documents 4 to 7). In such a head with a small droplet size, the nozzle diameter is small, so that the evaporation of ink from the tip of the nozzle tends to proceed. For this reason, the ejection performance required for ink has become more severe.

  Generally speaking, the discharge stability does not indicate a single performance, and there are several conditions listed as the premise of the discharge stability. For example, stability during continuous ejection, recovery after long-term standing, ejection stability after short-term standing, and the like. Here, the short-term neglect means, for example, a case where there is a discharge time interval in a state where the discharge head is not capped. Therefore, the ease of evaporation is also affected by the nozzle shape. In particular, when a head having a small droplet size is used, the ejection performance after being left for a short period is very important as the performance of the ink.

  Various proposals have been made for methods for improving ink performance with respect to ejection stability after short-term standing (see, for example, Patent Documents 8 to 10). In these proposals, improvement in dye solubility, suppression of increase in viscosity during ink evaporation, and relaxation of dye aggregation during complete evaporation of volatile components are improved, thereby improving ejection stability after standing for a short time.

JP-A 63-139964 JP-A-6-136306 Japanese Patent Laid-Open No. 9-111165 Japanese Patent Laid-Open No. 4-10940 JP-A-4-10941 JP-A-4-10942 JP 4-12859 A Japanese Patent Publication No. 60-042834 JP-A-4-21469 JP-A-5-070726

  However, even when these means are used, when a surfactant or the like is added for the purpose of improving the suitability for recording on plain paper, the ejection stability after standing for a short time may be lowered.

  Accordingly, an object of the present invention is to provide an ink having excellent performance in recording on plain paper and excellent discharge characteristics, particularly discharge stability after being left for a short time. Furthermore, the present invention provides an ink tank containing such ink, thereby enabling stable high-quality image formation.

The above object is achieved by the present invention described below. That is, the present invention is an inkjet ink comprising at least a coloring material, water, a water-soluble organic solvent, and a surfactant, wherein the surfactant is a compound represented by the following general formula (I) and the following general formula: The ratio ((I) / (II)) of the content of each compound represented by the general formula (I) and the general formula (II) in the ink including the compound represented by the formula (II) is mass. Ink-jet ink (hereinafter referred to as “ink”), characterized in that it is in the range of 1/1 to 10/1 on a standard basis and the total content of these compounds in the ink is 0.2% by mass or more. ).

  According to the present invention, it is possible to provide an ink that is excellent in printability on plain paper and excellent in ejection stability after being left for a short time.

  Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. First, the operation of obtaining the above excellent effect by the configuration of the present invention will be described.

  The inventors of the present invention conducted various studies on additives such as surfactants contained in inks, recording properties on plain paper, and ejection stability after short-term storage. As a result, by adding at least two kinds of surfactants represented by the above general formulas (I) and (II), the recording property of plain paper is excellent, and the decrease in ejection stability after short-term standing is also reduced. The inventors have found what can be done and have reached the present invention. In particular, as a result of investigation, when the above two types of compounds are used in combination, even when the amount of these compounds is used alone, even if the amount is small, bleeding between colors on plain paper begins. It was found to be excellent in suppressing (hereinafter referred to as bleed). It was also found that even when the amount added is large, the deterioration of the discharge performance after standing for a short period of time is small.

  About the above-mentioned effect | action, the present inventors estimate as follows. When the dynamic surface tension of the compounds represented by the general formulas (I) and (II) is measured, the compound represented by the general formula (I) is shorter in time (several tens to several hundreds msec). Excellent surface tension reducing ability. On the other hand, the compound represented by the general formula (II) is excellent in surface tension reducing ability for a long time (about 1,000 msec or more). By using two kinds of surfactants having different surface tension reducing characteristics in this way, the surface tension can be kept low over the entire time range even in a small amount, compared with the case where each is used alone. It is thought that the bleed performance with paper was improved.

  In addition, the cause of deterioration of ejection stability after standing for a short time by adding a surfactant is unknown, but the factor is that the surfactant is oriented on the nozzle surface and partially increases the viscosity. It is estimated that there is not. On the other hand, when two or more kinds of surfactants having different surface tension reducing ability are mixed as in the ink according to the present invention, it is presumed that there is a change in the orientation state of the surfactant on the nozzle surface. That is, due to the difference in surface tension reducing ability, the compound represented by the general formula (I) is oriented on the surface in a short time, and the compound represented by the general formula (II) is oriented on the surface in a long time. Conceivable. And the change of the alignment state with this time and the viscosity increase due to the orientation of the surfactant, etc., because one kind of surfactant is not oriented alone, but two or more kinds of surfactant are mixed and oriented. As a result, it is estimated that the ejection stability after being left for a short time has been improved.

  Next, each component constituting the ink according to the present invention will be described. First, the compounds represented by the general formulas (I) and (II) to be added as the surfactant characterizing the ink according to the present invention will be described, respectively, and other components will be described.

1. Compound Represented by General Formula (I) In the present invention, a compound represented by the following general formula (I) is used as the first surfactant.

  As described above, in the present invention, the value of m + n in the general formula (I), that is, the ethylene oxide addition amount is in the range of 7 to 13 is used. That is, when it is smaller than 7, the solubility in water is lowered, and when it is larger than 13, the surface activity is low and the suitability for recording on plain paper is lowered. A more preferable compound is m + n = 10.

2. Compound Represented by General Formula (II) In the present invention, a compound represented by the following general formula (II) is used as the second surfactant.

  As described above, in the present invention, a compound in which s in the general formula (II) is in the range of 6 to 11 and t + u which is the addition amount of ethylene oxide is in the range of 3 to 10 is used. When s is smaller than 6 or t + u is larger than 10, the surface activity is low and the suitability for recording on plain paper is lowered. On the other hand, when s is larger than 11 or t + u is smaller than 3, the solubility in water decreases. More preferable compounds are those in which s = 9 and t + u is 5 to 10, and further s = 9 and t + u = 5.

  The ratio ((I) / (II)) of the compound represented by the general formula (I) and the general formula (II) added to the ink as a surfactant is 1/1 or more and 10 or more on a mass basis. / 1 or less. If the content of the compound represented by the general formula (II) is larger than this range, the suitability for recording on plain paper is lowered, and if it is small, the combined use effect cannot be obtained. Furthermore, the total content of the compounds represented by the general formulas (I) and (II) in the ink is 0.2% by mass or more.

3. Water-soluble organic solvent As the water-soluble organic solvent constituting the ink according to the present invention, any of those conventionally used together with water as a component of an aqueous ink for inkjet can be used. Specific examples include alcohols, polyhydric alcohols, polyglycols, glycol ethers, nitrogen-containing polar solvents, sulfur-containing polar solvents, ureas, and saccharides. These water-soluble organic solvents are used for the purpose of imparting functions such as maintaining the moisture retention of the ink and improving the solubility and dispersibility of the coloring material. These water-soluble organic solvents can be used alone or in combination.

  Further, the upper limit of the content of these water-soluble organic solvents to be contained in the ink is preferably 50% by mass or less, more preferably 40% by mass or less based on the whole ink. Further, the lower limit of inclusion is preferably 1% by mass or more, more preferably 3% by mass or more of the whole ink. Furthermore, the content of water in the ink is preferably in the range of 30% by mass to 95% by mass in order to maintain good dye solubility and ink ejection stability. As water, it is preferable to use ion-exchanged water.

4). Coloring materials Specific examples of coloring materials that can be used as constituent components of the ink according to the present invention are given below, but the present invention is not limited to these. That is, the color material of the ink used in the present invention may be a commonly used color material such as a commonly used dye or pigment, or a newly synthesized color material. It can be appropriately selected and used within the range. The lower limit of the content of the color material contained in the ink is preferably 0.1% by mass or more, more preferably 1.0% by mass or more. Moreover, as an upper limit, Preferably it is 15 mass% or less, More preferably, 7 mass% or less is good. These color materials to be contained in the ink can be used alone or in combination of two or more.

  As the water-soluble dye that can be used in the present invention, any of a direct dye, an acid dye, a reactive dye, and a basic dye can be used. Even those not described in the color index can be used as long as they are water-soluble dyes.

The following are mentioned as an example of dye.
C. I. Direct black: 17, 19, 22, 31, 32, 51, 62, 71, 74, 112, 113, 154, 168, 195;
C. I. Acid Black: 2, 48, 51, 52, 110, 115, 156;
C. I. Food black: 1, 2;
C. I. Direct Red: 2, 4, 9, 11, 20, 23, 24, 31, 39, 46, 62, 75, 79, 80, 83, 89, 95, 197, 201, 218, 220, 224, 225, 226 227, 228, 229, 230;
C. I. Acid Red: 6, 8, 9, 13, 14, 18, 26, 27, 32, 35, 42, 51, 52, 80, 83, 87, 89, 92, 106, 114, 115, 133, 134, 145 158, 198, 249, 265, 289;
C. I. Food Red: 87, 92, 94;
C. I. Direct violet: 107;
C. I. Direct blue: 1, 15, 22, 25, 41, 76, 77, 80, 86, 90, 98, 106, 108, 120, 158, 163, 168, 199, 226, 307;
C. I. Acid Blue: 1, 7, 9, 15, 22, 23, 25, 29, 40, 43, 59, 62, 74, 78, 80, 90, 100, 102, 104, 112, 117, 127, 138, 158 161, 203, 204, 221, 244;
C. I. Direct yellow: 8, 11, 12, 27, 28, 33, 39, 44, 50, 58, 85, 86, 87, 88, 89, 98, 100, 110, 132, 173;
C. I. Acid Yellow: 1, 3, 7, 11, 17, 23, 25, 29, 36, 38, 40, 42, 44, 76, 98, 99

（上記一般式（III）中、Ｍは、アルカリ金属又はアンモニウムであり、Ｒ₁及びＲ₂は、それぞれ独立に、水素原子、スルホン酸基、カルボキシル基（但し、Ｒ₁、Ｒ₂は、同時に水素原子となる場合を除く。）を表し、Ｙは、塩素原子、ヒドロキシル基、アミノ基、モノ又はジアルキルアミノ基で表されるフタロシアニン化合物及びその塩を表し、ｌ、ｍ、ｎは、ｌ＝０乃至２、ｍ＝１乃至３、ｎ＝１乃至３、但し、ｌ＋ｍ＋ｎ＝３乃至４、置換基の置換位置は、４若しくは４’位を表す。）が挙げられる。 Further, a copper phthalocyanine compound having a structure represented by the following general formula (III) can be used.

(In the above general formula (III), M is an alkali metal or ammonium, and R ₁ and R ₂ are each independently a hydrogen atom, a sulfonic acid group, or a carboxyl group (provided that R ₁ and R ₂ are simultaneously Y represents a phthalocyanine compound represented by a chlorine atom, a hydroxyl group, an amino group, a mono- or dialkylamino group and a salt thereof, and l, m, and n are l = 0 to 2, m = 1 to 3, n = 1 to 3, provided that l + m + n = 3 to 4, and the substitution position of the substituent represents the 4 or 4 ′ position.

As an example of the pigment that can be used in the present invention, carbon black is preferably used for the black ink. For example, carbon black pigments such as furnace black, lamp black, acetylene black, and channel black, and more specifically, the following products can be used.
For example, Raven 7000, Ray Van 5750, Ray Van 5250, Ray Van 5000ULTRA, Ray Van 3500, Ray Van 2000, Ray Van 1500, Ray Van 1250, Ray Van 1200, Ray Van 1190 ULTRA-II, Ray Van 1170, Ray Van 1255 (manufactured by Columbia).
Black Pearls L, Regal 400R, Legal 330R, Legal 660R, Mogul L, Monarch 700, Monak 800, Monak 880, Monak 900, Monak 1000, Monak 1100, Monak 1300, Monak 1400, Valcan XC-72R (above Cabot);
Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color Black S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V Printex 140U, Printex 140V, Special Black 6, Special Black 5, Special Black 4A, Special Black 4 (manufactured by Degussa);
No. 25, no. 33, no. 40, no. 47, no. 52, no. 900, no. 2300, MCF-88, MA600, MA7, MA8, MA100 (manufactured by Mitsubishi Chemical Corporation);
Commercially available products such as those newly prepared separately can also be used.

  As the pigment used in the color ink, an organic pigment is preferably used. Specific examples include the following. Insoluble azo pigments such as Toluidine Red, Toluidine Maroon, Hansa Yellow, Benzidine Yellow, and Pyrazolone Red. Soluble azo pigments such as Ritolol Red, Helio Bordeaux, Pigment Scarlet, and Permanent Red 2B. Derivatives from vat dyes such as alizarin, indanthrone and thioindigo maroon. Phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green. Quinacridone pigments such as quinacridone red and quinacridone magenta. Perylene pigments such as perylene red and perylene scarlet. Isoindolinone pigments such as isoindolinone yellow and isoindolinone orange. Imidazolone pigments such as benzimidazolone yellow, benzimidazolone orange, and benzimidazolone red; Pilanthrone pigments such as pyranthrone red and pyranthrone orange. Thioindigo pigments, condensed azo pigments, thioindigo pigments, diketopyrrolopyrrole pigments. Flavanthrone yellow, acylamide yellow, quinophthalone yellow, nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, dianthraquinonyl red, dioxazine violet, etc.

Moreover, when an organic pigment is shown by a color index (CI) number, the following can be illustrated.
C. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93, 97, 109, 110, 117, 120, 125, 128, 137, 138, 147, 148, 150, 151, 153, 154, 166, 168, 180, 185;
C. I. Pigment orange 16, 36, 43, 51, 55, 59, 61, 71;
C. I. Pigment Red 9, 48, 49, 52, 53, 57, 97, 122, 123, 149, 168, 175, 176, 177, 180, 192, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, 254, 255, 272;
C. I. Pigment violet 19, 23, 29, 30, 37, 40, 50;
C. I. Pigment blue 15, 15: 1, 15: 3, 15: 4, 15: 6, 22, 60, 64;
C. I. Pigment green 7, 36;
C. I. Pigment Brown 23, 25, 26

  The pigment that can be used in the present invention may be either a self-dispersing pigment or a pigment that is dispersed by adsorption of a dispersing agent. As the pigment dispersant, any water-soluble resin can be used. Specifically, a block copolymer, a random copolymer, or a graft comprising at least two monomers selected from the following monomers (of which at least one is a hydrophilic monomer) Examples thereof include copolymers and salts thereof. Alternatively, natural resins such as rosin, shellac and starch can be preferably used. The following are mentioned as a monomer. For example, styrene, styrene derivatives, vinyl naphthalene, vinyl naphthalene derivatives, aliphatic alcohol esters of α, β-ethylenically unsaturated carboxylic acids, acrylic acid, acrylic acid derivatives, maleic acid, maleic acid derivatives, itaconic acid, itaconic acid Derivatives, fumaric acid, fumaric acid derivatives, vinyl acetate, vinyl pyrrolidone, acrylamide, and derivatives thereof. These resins are soluble in an aqueous solution in which a base is dissolved, and are alkali-soluble resins.

  Furthermore, in addition to the above components, the ink according to the present invention includes a pH adjuster, a rust inhibitor, an antiseptic, a fungicide, an antioxidant, an anti-reduction agent, an evaporation accelerator, and a chelating agent as necessary. Various additives such as a water-soluble polymer may be contained. The ink is preferably adjusted to have a desired viscosity and pH in order to obtain good ejection characteristics in the ink jet recording apparatus.

  In the recording method of the present invention, inks of a plurality of colors are used to form a full color image. For example, cyan ink, magenta ink, yellow ink, black ink, red ink, green ink, blue ink, and the like. Further, these inks can be used in combination with light inks having the same color tone. As the color material of ink having these different colors or light ink, a publicly known dye or pigment, or a newly synthesized color material can be used.

(Recording device)
The above-described ink according to the present invention has been developed particularly for ink jet recording. In this case, examples of the ink jet recording method and the ink jet recording apparatus that are particularly suitable include a method and apparatus for applying thermal energy corresponding to the recording signal to the ink in the recording head chamber and generating droplets by the thermal energy. .

(Device body)
1 and 2 show schematic configuration examples of a printer using an ink jet recording method. In FIG. 1, the outer shell of the printer apparatus main body M1000 in this embodiment includes an exterior member and a chassis M3019 (see FIG. 2) housed in the exterior member. The exterior member includes a lower case M1001, an upper case M1002, an access cover M1003, and a discharge tray M1004.

  The chassis M3019 is composed of a plurality of plate-shaped metal members having a predetermined rigidity, forms a skeleton of the recording apparatus, and holds each recording operation mechanism described later. Further, the exterior of the apparatus main body M1000 has a storage space for storing each mechanism described later by combining both the lower case M1001 of the substantially lower half and the upper case M1002 of the substantially upper half. It has a hollow body structure. An opening is formed in each of the upper surface portion and the front surface portion of the apparatus main body M1000.

  Further, one end of the discharge tray M1004 is rotatably held by the lower case M1001, and the opening formed on the front surface of the lower case M1001 can be opened and closed by the rotation. For this reason, when performing the recording operation, the discharge tray M1004 is rotated to the front side to open the opening, so that the recording sheets can be discharged and the discharged recording sheets P are sequentially stacked. To get. In addition, the discharge tray M1004 contains two auxiliary trays M1004a and M1004b. By pulling out each tray as needed, the paper support area can be expanded or reduced in three stages. It has become.

  One end of the access cover M1003 is rotatably held by the upper case M1002, and an opening formed on the upper surface can be opened and closed. Then, by opening the access cover M1003, the recording head cartridge H1000 or the ink tank H1900 stored in the main body can be replaced. Although not particularly shown here, when the access cover M1003 is opened and closed, a protrusion formed on the back surface of the access cover M1003 rotates the cover opening and closing lever. The open / closed state of the access cover can be detected by detecting the rotation position of the lever with a micro switch or the like.

  Further, a power key E0018 and a resume key E0019 are provided on the upper surface of the rear portion of the upper case M1002 so as to be depressable. Along with these, an LED E0020 is provided, and when the power key E0018 is pressed, the LED E0020 is lit to notify the operator that recording is possible. The LED E0020 has various display functions such as blinking and color change, and informing the operator of printer troubles. When the trouble is solved, the recording is resumed by pressing the resume key E0019.

(Recording mechanism)
Next, the recording operation mechanism in the present embodiment that is housed and held in the printer apparatus main body M1000 will be described. As a recording operation mechanism in the illustrated apparatus, an automatic feeding unit M3022 that automatically feeds the recording sheet P into the apparatus main body, and a recording sheet P that is sent one by one from the automatic feeding unit are recorded on a predetermined basis. It has a mechanism for guiding it to a position. Along with this, a conveyance unit M3029 for guiding the recording sheet P from the recording position to the discharge unit M3030 and a recording unit for performing desired recording on the recording sheet P conveyed to the recording position are provided. Furthermore, a recovery unit (M5000) for performing recovery processing on the recording unit or the like is provided (see FIG. 2).

(Recording part)
Here, the recording unit will be described. The recording unit includes a carriage M4001 that is movably supported by a carriage shaft M4021, and a recording head cartridge H1000 that is detachably mounted on the carriage M4001 (see FIG. 3). ).

(Recording head cartridge)
Next, the recording head cartridge used in the recording unit will be described with reference to FIGS. The recording head H1001 according to the present invention is one constituent element of the recording head cartridge H1000 as can be seen from the perspective views of FIGS. 3 (a) and 3 (b). The recording head cartridge H1000 includes a recording head H1001 and an ink tank H1900 (H1901, H1902, H1903, H1904) that is detachably provided on the recording head H1001. The recording head cartridge H1000 is fixedly supported by positioning means and electrical contacts of a carriage M4001 mounted on the ink jet recording apparatus main body, and is detachable from the carriage M4001.

  H1901 is an ink tank for black ink, H1902 is for cyan ink, H1903 is for magenta ink, and H1904 is an ink tank for yellow ink. In the exemplary apparatus, each of the ink tanks of each color is detachable from the recording head H1001, and each tank can be replaced, so that the running cost of printing in the ink jet recording apparatus is reduced. .

  Next, the print head H1001 will be described in detail for each component constituting the print head. 4 to 6 are explanatory views for explaining each of the preferred head cartridge, the recording head, and the ink tank and the relationship thereof to which the present invention is applied or applied. Hereinafter, each component will be described with reference to these drawings.

(1) Recording Head The recording head H1001 is a bubble jet (registered trademark) side that performs recording using an electrothermal transducer that generates thermal energy for causing film boiling in ink according to an electrical signal. This is a recording head that is of a shooter type.

(1-1) Recording Element Unit FIG. 4 is a partially exploded perspective view for explaining the configuration of the first recording element substrate H1100. The first recording element substrate H1100 is formed, for example, by forming an ink supply port H1102 having a long groove-like through-hole as an ink channel on a Si substrate H1110 having a thickness of 0.5 mm to 1 mm. The ink supply port is formed by a method such as anisotropic etching or sandblasting using the crystal orientation of Si. Then, on both sides of the ink supply port H1102, the electrothermal conversion elements H1103 are arranged in a staggered pattern, one row each. The electrothermal conversion element H1103 and electric wiring such as Al for supplying electric power to the electrothermal conversion element H1103 are formed by a film forming technique. Furthermore, electrode portions H1104 for supplying power to the electrical wiring are arranged on both outer sides of the electrothermal transducer H1103, and bumps H1105 such as Au are formed on the electrode portion H1104. On the Si substrate, an ink channel wall H1106 and an ejection port H1107 for forming an ink channel corresponding to the electrothermal conversion element H1103 are formed of a resin material by a photolithography technique to form an ejection port group H1108. is doing. Accordingly, since the ejection port is provided to face the electrothermal conversion element H1103, the ink supplied from the ink flow path H1102 is ejected by bubbles generated by the electrothermal conversion element H1103.

  FIG. 5 is a partially exploded perspective view for explaining the configuration of the second recording element substrate H1101. The second recording element substrate H1101 is a recording element substrate for discharging ink of three colors, and has three ink supply ports H1102 formed in parallel. Electrothermal conversion elements and ink discharge ports are formed on both sides of each ink supply port. Of course, similarly to the first recording element substrate H1100 described above, an ink supply port, an electrothermal conversion element, electric wiring, an electrode portion, and the like are formed on the Si substrate, and a resin material is formed on the Si substrate by photolithography technology. An ink flow path and an ink discharge port are formed. Similarly to the first recording element substrate, a bump H1105 such as Au is formed on the electrode portion H1104 for supplying power to the electric wiring.

Next, the first plate H1200 is formed of an alumina (Al ₂ O ₃ ) material having a thickness of 0.5 mm to 10 mm, for example. Note that the material of the first plate is not limited to alumina. For example, even if it is made of a material having a linear expansion coefficient equivalent to that of the material of the recording element substrate H1100 and a thermal conductivity equal to or higher than that of the material of the recording element substrate H1100. Good. As a material of the first plate H1200, for example, any of silicon, aluminum nitride (AlN), zirconia, silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), molybdenum, and tungsten may be used.

  An ink supply port H1102 for supplying black ink to the first recording element substrate H1100 and an ink supply port H1102 for supplying each color ink to the second recording element substrate H1101 are formed in the first plate H1200. Yes. The ink supply port H1102 of the recording element substrate corresponds to the ink supply port H1102 of the first plate H1200. Further, the first recording element substrate H1100 and the second recording element substrate H1101 are bonded and fixed to the first plate H1200 with high positional accuracy. The first adhesive H1202 used for bonding at this time is desirably a low viscosity, low curing temperature, cured in a short time, has a relatively high hardness after curing, and has ink resistance. The first adhesive H1202 is, for example, a thermosetting adhesive mainly composed of an epoxy resin, and the thickness of the adhesive layer is desirably 50 μm or less.

  The electrical wiring tape H1300 applies an electrical signal for ejecting ink to the first recording element substrate H1100 and the second recording element substrate H1101. A plurality of openings for incorporating the respective recording element substrates, electrode terminals H1302 (not shown) corresponding to the electrode portions H1104 of the respective recording element substrates, and ends of the wiring tape are positioned from the main unit. An electrical contact substrate H2200 having an external signal input terminal H1301 for receiving an electrical signal and an electrode terminal portion H1303 (not shown) for electrical connection are provided. The electrode terminal H1302 and the electrode terminal 1303 are connected by a continuous copper foil wiring pattern.

  The electrical wiring tape H1300, the first recording element substrate 1100, and the second recording element substrate H1101 are electrically connected to each other. As for the connection method, for example, the electrode portion H1104 of the recording element substrate and the electrode terminal H1302 of the electric wiring tape H1300 are electrically joined by a thermosonic bonding method.

The second plate H1400 is, for example, a single plate-like member having a thickness of 0.5 mm or more and 1 mm or less, and is formed of a ceramic material such as alumina (Al ₂ O ₃ ) or a metal material such as Al or SUS. Has been. The first recording element substrate H1100 and the second recording element substrate H1101 that are bonded and fixed to the first plate H1200 have openings that are larger than the outer dimensions thereof. In addition, the first recording element substrate H1100 and the second recording element substrate H1101 and the electric wiring tape H1300 are bonded to the first plate H1200 with a second adhesive H1203 so that they can be electrically connected in a plane. The back surface of the electrical wiring tape H1300 is bonded and fixed with a third adhesive H1306.

  The first recording element substrate H1100, the second recording element substrate H1101, and the electrical connection portion of the electrical wiring tape H1300 are sealed with a first sealant H1307 (not shown) and a second sealant H1308. Yes. As a result, the electrical connection portion is protected from ink corrosion and external impact. The first sealing agent mainly seals the back surface side of the connection portion between the electrode terminal H1302 of the electric wiring tape and the electrode portion H1105 of the recording element substrate and the outer peripheral portion of the recording element substrate, and the second sealing agent. Seals the front side of the connecting part.

  Further, an electrical contact substrate H2200 having an external signal input terminal H1301 for receiving an electrical signal from the main body device at the end of the electrical wiring tape is electrically connected by thermocompression bonding using an anisotropic conductive film or the like. . The electric wiring tape H1300 is bent at one side surface of the first plate H1200, and is bonded to the side surface of the first plate H1200 with a third adhesive H1306 (not shown). As the third adhesive H1306, for example, a thermosetting adhesive having an epoxy resin as a main component and a thickness of 10 μm or more and 100 μm or less is used.

(1-2) Ink Supply Unit The ink supply member H1500 is formed by resin molding, for example. As the resin material, it is desirable to use a resin material mixed with 5% by mass or more and 40% by mass or less of a glass filler in order to improve the shape rigidity.

  As shown in FIG. 6, the ink supply member H1500 is a component of the ink supply unit H1003 for guiding ink from the ink tank H1900 to the recording element unit H1002. The ink supply member H1500 forms an ink flow path H1501 by ultrasonically welding the flow path forming member H1600. Further, a filter H1700 for preventing entry of dust from the outside is joined to a joint H1517 engaged with the ink tank H1900 by welding. Further, a seal rubber H1800 is attached to prevent ink from evaporating from the joint H1517.

  The ink supply member H1500 also has a part of the function of holding the removable ink tank H1900, and has a first hole H1503 for engaging the second claw H1910 of the ink tank H1900. Further, a mounting guide H1601 for guiding the recording head cartridge H1000 to the mounting position on the carriage M4001 of the ink jet recording apparatus main body, and an engaging portion H1508 for mounting and fixing the recording head cartridge to the carriage M4001 by a head set lever are provided. . Further, an abutting portion H1509 in the X direction (carriage scan direction) for positioning the carriage M4001 at a predetermined mounting position, an abutting portion H1510 in the Y direction (recording medium conveyance direction), and an abutting portion in the Z direction (ink ejection direction). A contact portion H1511 is provided. Further, a terminal fixing portion H1512 for positioning and fixing the electrical contact substrate H2200 of the recording element unit H1002 is provided. A plurality of ribs are provided around the terminal fixing portion H1512 and the periphery thereof to increase the rigidity of the surface having the terminal fixing portion H1512.

(2) Description of Print Head Cartridge FIGS. 3A and 3B described above are diagrams for explaining mounting of the print head H1001 and the ink tanks H1901, H1902, H1903, and H1904 constituting the printhead cartridge H1000. The ink tanks H1901, H1902, H1903, and H1904 contain corresponding color inks. Further, as shown in FIG. 6, each ink tank is formed with an ink supply port H1907 for supplying ink in the ink tank to the recording head H1001. For example, when the ink tank H1901 is attached to the recording head H1001, the ink supply port H1907 of the ink tank H1901 is brought into pressure contact with the filter H1700 provided in the joint portion H1520 of the recording head H1001, and the black ink in the ink tank H1901 is ink. The ink is supplied from the supply port H1907 to the first recording element substrate through the first plate H1200 through the ink flow path H1501 of the recording head H1001. Then, ink is supplied to the bubbling chamber H1109 having the electrothermal conversion element H1103 and the discharge port H1107, and is discharged toward a recording sheet as a recording medium by the thermal energy given to the electrothermal conversion element H1103.

  Hereinafter, although it demonstrates more concretely using an Example and a comparative example, this invention is not limited by the following Example, unless the summary is exceeded. In the following description, “%” is based on mass unless otherwise specified.

<Examples and comparative examples>
The components shown in Tables 1-1 and 1-2 were mixed, sufficiently stirred and dissolved, and then subjected to pressure filtration with a 0.20 μm filter to prepare inks according to Examples and Comparative Examples. The color material is a copper phthalocyanine compound having the structure represented by the general formula (III) shown above, wherein the substituted sulfamoyl group in the formula (III) is represented by the following formula (IV), and M is sodium. A compound was used.

<Color material adjustment>
(1) Synthesis of copper phthalocyanine tetrasulfonic acid tetrasodium salt (formula (V))

  Sulfolane, 4-sulfophthalic acid monosodium salt, ammonium chloride, urea, ammonium molybdate, and copper (II) chloride were stirred, washed with methanol, water was added, and the pH was adjusted to 11 with an aqueous sodium hydroxide solution. Then, an aqueous hydrochloric acid solution was added with stirring, and sodium chloride was gradually added thereto. The precipitated crystals are filtered and washed with a 20% aqueous sodium chloride solution. Subsequently, methanol is added and the precipitated crystals are separated by filtration, washed with a 70% aqueous methanol solution and dried to obtain the desired copper phthalocyanine tetrasulfonic acid tetrasodium salt. Obtained as blue crystals.

(2) Synthesis of copper phthalocyanine tetrasulfonic acid chloride (formula (VI))

  The copper phthalocyanine tetrasulfonic acid tetrasodium salt obtained above was gradually charged into chlorosulfonic acid, and thionyl chloride was added dropwise to carry out the reaction. Thereafter, the reaction solution was cooled, and the precipitated crystals were filtered to obtain a copper phthalocyanine tetrasulfonic acid chloride wet cake.

(3) Synthesis of compound represented by formula (VII)

  Lipal OH, cyanuric chloride, aniline-2,5-disulfonic acid monosodium salt were added to ice water, and the reaction was carried out while adding an aqueous sodium hydroxide solution. Next, an aqueous sodium hydroxide solution was added to the reaction solution to adjust the pH of the reaction solution to 10. To this reaction solution, 28% ammonia water and ethylenediamine were added for reaction. Sodium chloride and concentrated hydrochloric acid were added dropwise to the resulting reaction solution to precipitate crystals. The precipitated crystals were collected by filtration and washed with a 20% aqueous sodium chloride solution to obtain a wet cake. Methanol and water were added to the obtained wet cake, further filtered, washed with methanol, and dried to obtain a compound represented by the formula (VII).

(4) Synthesis of coloring material used in Examples The wet cake of copper phthalocyanine tetrasulfonic acid chloride (formula (VI)) obtained in (2) was added to ice water and suspended by stirring. The reaction was carried out by adding the compound represented by the formula (VII) obtained in (3). Water and sodium chloride were added to this to precipitate crystals. The obtained crystals were filtered, washed with an aqueous sodium chloride solution, filtered again, washed and dried to obtain a color material as blue crystals. From the above reaction, this compound is a colorant whose average number of substituents in formula (III) is 1 = 0, m = 1.0 to 2.0, and n = 2.0 to 3.0. It is estimated to be.

  In the table, compound (a) is a compound of s = 9 and t + u = 2 in the general formula (II).

<Evaluation of ink>
Each of the inks of Examples 1 to 5 and Comparative Examples 1 to 9 obtained above was accommodated in an ink tank, and an image was printed using a color inkjet printer PIXUS960i (trade name, manufactured by Canon Inc.) equipped with these inks. Formed and evaluated according to the following methods and criteria. The color inkjet printer used here is an inkjet recording apparatus having an on-demand type multi-recording head that ejects ink by applying thermal energy corresponding to a recording signal to the ink. Tables 2-1 and 2-2 show the evaluation results obtained using these inks.

(Applicability to printing on plain paper)
Each of the inks of Examples 1 to 5 and Comparative Examples 1 to 9 was used as the cyan ink, BCI-6Y ink (manufactured by Canon Inc.) was used as the yellow ink, and cyan paper was applied to plain paper (office planner). Let me write yellow letters. About each obtained printed matter, the character quality was observed visually and evaluated on the following reference | standard.

○: Characters within a 7 mm square can be clearly printed.
(Triangle | delta): The character within 15 mm square can be printed clearly.
X: Characters in a side of 15 mm square are unclear.

(Discharge stability after short-term standing)
In a dry environment of 15 ° C. and 10% RH, after ink is ejected, it is ejected again after a certain period of time, and when dots are drawn on the high-quality exclusive paper HR-101 (trade name: manufactured by Canon), the dots are disturbed It was evaluated by the time until it occurred. The disturbance of dots was observed with an electron microscope, and the time from ink ejection to re-ejection was changed in seconds and evaluated according to the following criteria.
○: The dots are not disturbed for 6 seconds or more.
Δ: Disturbance does not occur in dots from 1 second to 5 seconds.
X: Disturbance does not occur in dots of less than 1 second

  As described above, by using an ink containing both the compound represented by the general formula (I) and the compound represented by the general formula (II) as the surfactant, the recording property on plain paper is excellent, and Ink with excellent ejection stability after being left for a short time can be provided.

1 is a perspective view illustrating an external configuration of an inkjet printer according to an embodiment of the present invention. It is a perspective view which shows the state which removed the exterior member of what is shown in FIG. FIG. 3A is a perspective view of a suitable recording head cartridge on which the ink jet recording head of the present invention can be mounted, and FIG. 3B is an exploded perspective view thereof. FIG. 4 is a partially cutaway explanatory perspective view showing a configuration of a recording element substrate of the recording head cartridge in FIG. 3. FIG. 4 is a partially cut-out explanatory perspective view illustrating a configuration of another recording element substrate of the recording head cartridge in FIG. 3. FIG. 4 is a cross-sectional view of a main part of the recording head cartridge in FIG. 3.

Claims (2)

An inkjet ink comprising at least a coloring material, water, a water-soluble organic solvent, and a surfactant, wherein the surfactant is a compound represented by the following general formula (I) and the following general formula (II): The ratio ((I) / (II)) in the ink of each compound represented by the general formula (I) and the general formula (II) in the ink is 1/1 on a mass basis. An inkjet ink characterized by being in the range of 10/1 or less and having a total content of these compounds in the ink of 0.2% by mass or more.

An ink tank provided with an ink storage portion, wherein the ink storage portion stores the ink-jet ink according to claim 1.

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