• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    ink set and inkjet recording method. an ink assembly, used in an ink jet recording apparatus equipped with a recording head that includes: a plurality of nozzle arrangements, each including a plurality of nozzles; and the recording head suck and cover unit, wherein black ink is supplied to one of the plurality of recording head nozzle arrangements, and color ink is supplied to the other plurality of recording head nozzle arrangements , where the black ink includes resin coated carbon black particles, carbon black particles treated with surfactant and water, where the color ink includes resin coated colored pigment particles, colored pigment particles treated with surfactant and water , and where the ink set satisfies expression (1), expression (2) and expression (3) below: 5.0% by mass less than p (bk) less than 12.0% by mass... expression (1), 3.0% in mass less equal to p(cl) less than 10.0% in mass ... expression (2), [r(cl) / s (cl)] less than [r ( bk) / s (bk)] ... expression (3).
    公开号:BR102013009182B1
    申请号:R102013009182-0
    申请日:2013-04-15
    公开日:2021-06-29
    发明作者:Keita Katoh；Masaki Kudo；Tomohiro Nakagawa；Akihiko Gotoh
    申请人:Ricoh Company, Ltd；
    IPC主号:
    专利说明:

    FUNDAMENTALS OF THE INVENTION Field of Invention
    [0001] The present invention relates to an ink assembly and an inkjet recording method. Description of Related Technique
    [0002] In an inkjet recording apparatus, a pigment ink that utilizes a pigment is used as it has superior water resistance and light fastness functionality. However, in the inkjet recording apparatus which uses pigment ink, ink discharge failure occurs due to clogging caused by ink thickened by drying or foreign matter, and there is a problem that stable discharge is not possible. A pigment ink having a high pigment concentration, especially a black ink having a high pigment concentration, which supports high desired image density in recent years, is likely to be thickened by drying, and discharge failure becomes more significant .
    [0003] Thus, for the purpose of improving discharge stability, an inkjet ink set that includes a black ink using either carbon black dispersed in water without a dispersant or carbon black included in a polymer and an ink different from black ink using a pigment included in a polymer is proposed (for example, see Japanese Patent Application Open Filed (JP-A) No. 2002-327138). However, with this proposed technology, there is a problem that the discharge stability is not sufficient for a high pigment concentration.
    [0004] Thus, to allow stable discharge for a high pigment concentration, an inkjet recording apparatus equipped with a print recovery and maintenance unit is proposed (eg see JP-A No. 2005-170035 ). The print recovery and maintenance unit sucks a filled ink into a nozzle by a negative pressure generating unit that communicates with a cap that seals a nozzle surface such as a suction pump and then sweeps the nozzle surface with a member. brush composed of an elastic plate such as rubber. In this way, air bubbles in a liquid chamber, thickened ink, dust and so on are removed, and a steady state for ink discharge is maintained.
    [0005] However, when viscous inks are being sucked using a common cap on a head that includes nozzle arrangements for discharging different types of inks such as combining a black carbon black ink and pigment ink of other colors, only thickened color pigment ink having a low viscosity compared to black ink is sucked in while black ink cannot be sucked in as carbon black black ink is likely to have a higher viscosity. Since no discharge occurs, a problem occurs that the non-discharge cannot be recovered.
    [0006] In this way, it is being requested at present the provision of an ink set that provides a high image density and has superior discharge stability and discharge recovery. SUMMARY OF THE INVENTION
    [0007] The present invention aims to solve the above problems in conventional technologies and to achieve the following objective. That is, the present invention aims to provide an ink assembly that provides a high image density and has superior discharge stability and discharge recovery.
    [0008] Means to solve the problems are as follows. That is, an ink set of the present invention is an ink set, which includes: a black ink; and a colored ink, wherein the ink assembly is used in an ink jet recording apparatus, which includes: a recording head which includes a plurality of nozzle arrangements, each including a plurality of nozzles; and at least one sucker and cover unit which covers the recording head and communicates with a suction generating unit, wherein the black ink is supplied to one of the plurality of nozzle arrangements of the recording head, and the colored ink is provided for the other plurality of recording head nozzle arrangements, wherein the black ink includes: resin coated carbon black particles that include carbon black and a resin that exists on a surface of the carbon black; surfactant-treated carbon black particles that include carbon black and a surfactant that exists on a surface of carbon black; and water, where the color ink includes: resin-coated color pigment particles that include a color pigment and a resin that exists on a surface of the color pigment; surfactant-treated color pigment particles that include a color pigment and a surfactant that exists on a surface of the color pigment; and water, where the ink set satisfies Expression (1), Expression (2), and Expression (3) below: 5.0% by mass < P(Bk) < 12.0% by mass... Expression (1) 3.0% in mass < P(CL) < 10.0% in mass ... Expression (2) [R(CL) / S(CL)] < [R(Bk) / S(Bk )] ... Expression (3) where, in Expression (1), P(Bk) represents a concentration of carbon black in the black ink; in Expression (2), P(CL) represents a pigment concentration of the colored ink; in Expression (3), R(Bk) represents a mass ratio of carbon black in resin coated carbon black particles to carbon black in black ink, S(Bk) represents a mass ratio of carbon black in the surfactant treated carbon black particles to the carbon black in the black ink, R(CL) represents a mass ratio of the colored pigment in the resin coated colored pigment particles to the colored pigment in the colored ink, and S(CL) ) represents a mass ratio of the colored pigment in the colored pigment particles treated with surfactant to the colored pigment in the colored ink.
    [0009] According to the present invention, conventional problems to be solved, and an ink set that provides high image density and has superior discharge stability and discharge recovery can be provided. BRIEF DESCRIPTION OF THE DRAWINGS
    [00010] FIG. 1 is a schematic plan view of an example of the recording head as viewed from a nozzle surface.
    [00011] FIG. 2 is a schematic plan view of another example of the recording head as viewed from a nozzle surface.
    [00012] FIG. 3 is a perspective diagram illustrating an example of an ink jet recording apparatus of the present invention.
    [00013] FIG. 4 is a schematic configuration diagram for explaining an overall configuration of a mechanical section of the ink jet recording apparatus of FIG. 3.
    [00014] FIG. 5 is a schematic configuration diagram of the mechanical section of the ink jet recording apparatus of FIG. 3.
    [00015] FIG. 6 is a schematic configuration diagram of a maintenance/recovery apparatus.
    [00016] FIG. 7 is a rough schematic configuration diagram of FIG. 6.
    [00017] FIG. 8 is a right side view of FIG. 6.
    [00018] FIG. 9 is a side view of the mechanical section that lifts and secures the cover. DETAILED DESCRIPTION OF THE INVENTION (ink set)
    [00019] An ink assembly of the present invention includes a black ink and a colored ink, and further includes other components as needed.
    [00020] The ink assembly is used in an ink jet recording apparatus equipped with: a recording head which includes a plurality of nozzle arrangements which includes a plurality of nozzles; and at least one suction and cover unit that covers the recording head and communicates with a suction generating unit.
    [00021] Black ink and color ink are respectively supplied for any of the recording head nozzle arrangements. <Black ink and color ink>
    [00022] The black ink includes resin coated carbon black particles, carbon black particles treated with surfactant and water, and preferably includes a water-soluble organic solvent, a fluorosurfactant and a silicone surfactant and additionally includes other components of according to need.
    [00023] The colored ink includes resin coated colored pigment particles, colored pigment particles treated with surfactant and water, and preferably includes a water-soluble organic solvent, a fluorosurfactant and a silicone surfactant and further includes other components according to the necessity.
    [00024] The ink set satisfies Expression (1), Expression (2) and Expression (3) below. 5.0% in mass < P(Bk) < 12.0% in mass ... Expression (1) 3.0% in mass < P(CL) < 10.0% in mass ... Expression (2) [R(CL) / S(CL)] < [R(Bk) / S(Bk)] ... Expression (3) where, in Expression (1), P(Bk) represents a concentration of carbon black from Black ink; in Expression (2), P(CL) represents a pigment concentration of the colored ink; in Expression (3), R(Bk) represents a mass ratio of carbon black in resin coated carbon black particles to carbon black in black ink, S(Bk) represents a mass ratio of carbon black in the surfactant treated carbon black particles to the carbon black in the black ink, R(CL) represents a mass ratio of the colored pigment in the resin coated colored pigment particles to the colored pigment in the colored ink, and S(CL) ) represents a mass ratio of the colored pigment in the colored pigment particles treated with surfactant to the colored pigment in the colored ink.
    [00025] It is necessary for a black ink which uses carbon black to have a high pigment concentration compared to a color ink which uses other color pigments in order to achieve sufficient image density. Furthermore, it is a usual case that carbon black itself has a particle diameter larger than a particle diameter of a colored pigment. Thus, black ink which uses carbon black is more likely to be viscous compared to colored ink which uses a colored pigment. When a recording head which shares nozzle arrangements with other colored inks is sealed with an identical cap to suck in viscous inks, only colored inks having a lower viscosity are sucked in while the thickened black ink is not sucked. Once the non-discharge occurs, a problem occurs where the non-discharge is not recovered.
    [00026] The present inventors have obtained the following findings with respect to such a problem.
    [00027] An ink which uses resin coated pigment particles that includes a pigment and a resin that exists on a pigment surface is slow to thicken when the ink dries in a nozzle compared to an ink which uses pigment particles treated with surfactants that include a pigment and a surfactant that exists on a surface of the pigment. Also, in an ink which uses the resin coated pigment particles and the surfactant treated pigment particles in combination, an ink thickening rate in a nozzle is lower for a higher ratio of the resin coated pigment particles. Thus, in an ink assembly that includes a black ink and a color ink which divides a cap, by using resin coated pigment particles and surfactant treated pigment particles in combination with a ratio of the color pigment particles coated with resin in color ink less than a ratio of resin-coated carbon black particles in black ink, an ink viscosity difference in a nozzle between black ink and color ink when thickened by drying and thus is reduced. This makes suction of inks through the lid easier, and flush stability and flush recovery are improved.
    [00028] Furthermore, it eliminates a need to reduce a concentration of pigment itself in the black ink, and thus sufficient image density of the black ink is also guaranteed.
    [00029] The present invention is completed based on the findings of the present inventors. Resin-coated carbon black particles and resin-coated colored pigment particles
    [00030] Resin coated carbon black particles are not particularly restricted since they are particles that include carbon black and a resin that exists on a surface of carbon black, and they can be appropriately selected according to the purpose .
    [00031] Resin coated colored pigment particles are not particularly restricted since they are particles that include a colored pigment and a resin that exists on a surface of the colored pigment, and they can be appropriately selected according to the purpose.
    [00032] Here below, carbon black and colored pigment may be collectively referred to as "pigments".
    [00033] Hereinafter, resin coated carbon black particles and resin coated colored pigment particles may collectively be referred to as "resin coated pigment particles".
    [00034] Resin coated pigment particles can also be defined as particles in which a pigment is coated with a resin. In resin-coated pigment particles, it is unnecessary that the pigment is completely covered with the resin; rather, the pigment is at least partially covered with the resin. - Resin -
    [00035] The resin is not particularly restricted, and can be appropriately selected according to the purpose. Examples thereof include a polyamide resin, a polyurethane resin, a polyester resin, a polyurea resin, an epoxy resin, a polycarbonate resin, a urea resin, a melamine resin, a phenolic resin, polysaccharides, gelatin , gum arabic, dextran, casein, natural rubber, carboxypolymethylene, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, cellulose, ethylcellulose, methylcellulose, nitrocellulose, hydroxyethylcellulose, cellulose acetate, polyethylene, polystyrene, polymers or (meth)acrylic acid copolymers, (meth)acrylic acid ester polymers or copolymers, (meth)acrylic acid-(meth)acrylic acid ester copolymers, a styrene-(meth)acrylic acid copolymer, copolymer of styrene-maleic acid, sodium alginate, fatty acids, paraffin, beeswax, water wax, hardened tallow, carnauba wax, albumin and others.
    [00036] Still, examples of the resin include: a resin that contains an anionic group such as carboxylic acid group, sulfonic acid group and others; and a resin that contains a nonionic group; and others. Examples of the resin containing a nonionic group include: homopolymers of polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate or methoxypolyethylene glycol monomethacrylate and copolymers thereof; cationic ring opening polyvinyl alcohol polymers or 2-oxazoline; and others.
    [00037] An amount of the resin in the resin coated pigment particles is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, it is preferably 10% by mass to 90% by mass, and more preferably 20% by mass to 70% by mass with respect to the pigment. When the amount of resin is less than 10% by mass, there are cases where a coating effect cannot be obtained. When the amount exceeds 90% by mass, there are cases where the pigment color development decreases. When the amount of resin is within the preferable range, it is possible to suppress the decrease in pigment color development since a resin content in the resin-coated pigment particles is relatively small. When the amount of resin is within the most preferable range, it is possible to suppress the decrease in pigment color development as a part of the pigment is substantially exposed within without being covered. In addition, as a part of the pigment is substantially exposed without being covered, it is possible to obtain an effect of the pigment being covered. Here, “substantially exposed” means intentional exposure rather than partial exposure due to defects such as pin holes, cracks and the like.
    [00038] A method to coat the pigment with the resin is not particularly restricted, it can be appropriately selected according to the purpose. Examples of it include a chemical process, a physical process, a physicochemical method, a mechanical process, and others. Specific examples thereof include an acid precipitation method, a phase inversion method, an interfacial polymerization method, an in-place polymerization method, a liquid-cured coating method, a coacervation (phase separation) method, a liquid drying method, a melt-dispersion-cooling method, an air suspension-coat method, a spray drying method and others. Among these, the liquid drying method, the acid precipitation method and the phase inversion method are preferable.
    [00039] The liquid drying method is not particularly restricted, and can be appropriately selected according to the purpose. For example, a dispersion liquid in which a pigment is dispersed in an organic solvent solution with a dissolved resin is prepared. Water is added to this dispersion liquid to form a composite emulsion, and the organic solvent in which the resin is dissolved is gradually removed. In this way, the pigment is coated with the resin.
    [00040] The phase inversion method is not particularly restricted, and can be appropriately selected according to the purpose. For example, an organic solvent phase is prepared as a mixture of an anionic group-containing resin having a self-dispersing ability or dissolving ability in water and the pigment or as a mixture of the pigment, a curing agent and a resin containing anionic group. By adding water to the organic solvent phase or by adding the organic solvent to water phase, the pigment is covered with the resin as it self-disperses (phase inversion emulsification).
    [00041] The acid precipitation method is not particularly restricted, and can be appropriately selected according to the purpose. For example, a wet cake is obtained by a kneading step of a resin containing anionic group in which the anionic group is partially or fully neutralized with a basic compound and pigment in an aqueous medium and a step of precipitation of the resin containing anionic group by adjusting the pH to neutral or acidic with an acidic compound in order to fix the same in the pigment. The wet cake anionic group is partially or fully neutralized using a basic compound, and in this way the pigment is covered with the resin. Carbon black
    [00042] Carbon black is not particularly restricted and can be appropriately selected according to the purpose.
    [00043] A method for manufacturing carbon black is not particularly restricted, and may be appropriately selected according to the purpose. Examples of it include an oven method, a channel method, and others.
    [00044] Like carbon black, commercial products can be used. Examples of commercial products include No. 2300, No. 900, MCF-88, No. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, No. 2200B (all manufactured by Mitsubishi Chemical Corporation) , RAVEN 700, 5750, 5250, 5000, 3500, 1255 (all manufactured by Columbian Chemicals Company), REGAL 400R, 330R, 660R, MOGULL, MONARCH 700, 800, 880, 900, 1000, 1100, 1300, MONARCH1400 (all manufactured by Cabot), color BLACK FW1, FW2, FW2V, FW18, FW200, S150, S160, S170 (all manufactured by Degussa), PRINTEX 35, U, V, 140U, 140V (all manufactured by Degussa), SPECIAL BLACK 6, 5 , 4A, 4 (all manufactured by Degussa) and others.
    [00045] A size of carbon black is not particularly restricted, and may be appropriately selected according to the purpose. Despite this, an average primary particle diameter thereof is preferably 15nm to 40nm.
    [00046] A specific surface area of carbon black is not particularly restricted, it can be appropriately selected according to the purpose. Despite this, a specific BET surface area thereof is preferably 50m2/g to 300m2/g. colored pigment
    [00047] The colored pigment is not particularly restricted, and can be appropriately selected according to the purpose. Examples of it include yellow pigments, magenta pigments, cyan pigments and others.
    [00048] The yellow pigments are not particularly restricted and can be appropriately selected according to the purpose. Examples thereof include CI Pigment Yellow 1 (Fast Yellow G), 2, 3, 12 (Disazoic Yellow AAA), 13, 14, 16, 17, 20, 23, 24, 34, 35, 37, 42 (Iron Oxide yellow), 53, 55, 73, 74, 75, 81, 83 (Disazoic Yellow HR), 86, 93, 95, 97, 98, 100, 101, 104, 108, 109, 110, 114, 117, 120, 125, 128, 129, 137, 138, 139, 147, 148, 150, 151, 153, 154, 155, 166, 168, 180, 185 and others.
    [00049] Magenta pigments are not particularly restricted and can be appropriately selected according to the purpose. Examples of this include CI Pigment Red 1, 2, 3, 5, 7, 9, 12, 17, 22 (Rapid Bright Scarlet), 23, 31, 38, 48:1 (Permanent Red 2B (Ba)), 48: 2 (Permanent Red 2B(Ca)), 48:3 (Permanent Red 2B(Sr)), 48:4 (Permanent Red 2B (Mn)), 49:1, 52:2, 53:1, 57:1 ( Brilliant Carmine 6B), 60:1, 63:1, 63:2, 64:1, 81 (Lake 6G Rhodamine), 83, 88, 92, 97, 101 (colcothar), 104, 105, 106, 108 (red of cadmium), 112, 114, 122 (dimethylquinacridone), 123, 146, 149, 166, 168, 170, 172, 175, 176, 178, 179, 180, 184, 185, 190, 192, 193, 202, 209 , 215, 216, 217, 219, 220, 223, 226, 227, 228, 238, 240, 254, 255, 272 and others.
    [00050] Cyan pigments are not particularly restricted and can be appropriately selected according to the purpose. Examples thereof include CI Pigment Blue 1, 2, 3, 15 (Phthalocyanine Copper Blue R), 15:1, 15:2, 15:3 (Phthalocyanine Blue G), 15:4, 15:6 (Phthalocyanine Blue E ), 16, 17:1, 22, 56, 60, 63, 64, Vat Blue 4, Vat Blue 60 and others.
    [00051] In addition, examples of pigments for neutral colors (red, green or blue) include CI Pigment Red 177, 194, 224, CI Pigment Orange 16, 36, 43, 51, 55, 59, 61, 71, CI Violet pigment 3, 19, 23, 29, 30, 37, 40, 50, CI Green pigment 7, 36 and others.
    [00052] A volume mean pigment particle diameter is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, it is preferably 10nm to 150nm, more preferably 20nm to 100nm, and particularly preferably 30nm to 80nm. When the volume mean particle diameter is less than 10nm, there are tendencies towards decreased lightfastness as well as degraded storage stability. When the volumetric average particle diameter exceeds 150nm, there are cases where a printed image has decreased color saturation, a stored ink thickens and aggregates, causing the nozzles to clog during printing.
    [00053] The volume mean particle diameter means a 50% mean particle diameter (D50) measured at 23°C, for example, by MICROTRAC UPA-150 manufactured by Nikkiso Co., Ltd. using a sample diluted with pure water such that a pigment concentration in the measurement sample is 0.01% by mass under conditions of particle refractive index of 1.51, particle density of 1.4g/cm3 and pure water parameters as solvent parameters. Carbon black particles treated with surfactant and colored pigment particles treated with surfactant
    [00054] Carbon black particles treated with surfactant are not particularly restricted since they are particles that include carbon black and a surfactant that exists on a surface of carbon black, and they can be appropriately selected according to the purpose .
    [00055] The colored pigment particles treated with surfactant are not particularly restricted as long as they are particles that include colored pigment and a surfactant that exists on a surface of the colored pigment, and they can be appropriately selected according to the purpose.
    [00056] Hereinafter, the surfactant treated carbon black particles and the surfactant treated colored pigment particles can be collectively referred to as “surfactant treated pigment particles”.
    [00057] The pigment particles treated with surfactant can be obtained by treating the pigment with the surfactant. Specifically, for example, they are obtained by dispersing the pigment in water using the surfactant.
    [00058] Examples of the pigment include carbon black, colored pigment and others. - Surfactant -
    [00059] The surfactant is not particularly restricted, and can be appropriately selected according to the purpose. Examples of the same include a nonionic surfactant, an anionic surfactant, an amphoteric surfactant and others.
    [00060] The non-ionic surfactant is not particularly restricted and can be appropriately selected according to the purpose. Examples thereof include: polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene myristyl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether and others; polyoxyethylene alkylphenyl ether such as polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether and others; polyoxyethylene-α-naphthyl ether, polyoxyethylene-β-naphthyl ether, polyoxyethylene monostyrylphenyl ether, polyoxyethylene distyrylphenyl ether, polyoxyethylene alkylnaphthyl ether, polyoxyethylene monostyrylnaphthyl ether, polyoxyethylene distyrylnaphthyl ether and others.
    [00061] Further, surfactants such as polyoxyethylene-polyoxypropylene block copolymers with polyoxyethylene in these surfactants partially substituted by polyoxypropylene or surfactants which compounds that include an aromatic ring such as polyoxyethylene alkylphenyl ether and others are condensed by formalin and others can also be used .
    [00062] An HLB value of the nonionic surfactant is not particularly restricted, and may be appropriately selected according to the purpose. Despite this, it is preferably 12.0 to 19.5, and more preferably 13.0 to 19.0. When the HLB value is 12.0 or greater, the surfactant does not fit well into a dispersion medium, and thus dispersion stability does not degrade. When the HLB value is 19.5 or less, the surfactant is hardly absorbed into the pigment, and thus the dispersion stability does not degrade.
    [00063] The anionic surfactant is not particularly restricted, and can be appropriately selected according to the purpose. Examples thereof include polyoxyethylene alkyl ether sulfate, polyoxyethylene alkylphenyl ether sulfate, polyoxyethylene monostyrylphenyl ether sulfate, polyoxyethylene distyrylphenyl ether sulfate, polyoxyethylene alkyl ether phosphate, polyoxyethylene alkylphenyl ether phosphate, polyoxyethylene monostyrylphenyl ether phosphate, polyoxyethylene distyrylphenyl ether phosphate, polyoxyethylene ether phosphate, polyoxyethylene alkylphenyl ether carboxylate, polyoxyethylene monostyrylphenyl ether carboxylate, polyoxyethylene distyrylphenyl ether carboxylate, naphthalene sulfonate formalin condensates, melanin sulfonate formalin condensates, dialkylsulfosuccinic acid ester salts, alkyl sulfosuccinate disalts, alkylsulfosuccinate di-salts, alkylsulfoacetic acid disulfoacetic acid , α-olefinsulfonate, alkylbenzenesulfonate, alkylnaphthalene sulfonate, alkylsulfonate, N-acylamino acid salts, acylated peptides, soaps and others.
    [00064] Metals used for these salts are not particularly restricted, and they may be appropriately selected according to the purpose. Examples of it include potassium, sodium, magnesium, calcium and others.
    [00065] A method to obtain the pigment particles treated with surfactant is not particularly restricted, and can be appropriately selected according to the purpose. Examples of this include a method of dispersing a mixture of pigment, surfactant and water in a mill.
    [00066] An amount of the surfactant to obtain the pigment particles treated with surfactant is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, it is preferably 10% by mass to 50% by mass with respect to the pigment. When the amount is 10% by mass or more, the storage stability of the pigment dispersion and the ink does not decrease, and the dispersion does not take a very long time. When the amount is 50% by mass or less, the ink viscosity does not increase excessively, and thus the discharge stability does not decrease.
    [00067] A concentration of carbon black in black ink [P(Bk)] is not particularly restricted as long as it satisfies Expression (1), and can be appropriately selected according to the purpose. Despite this, it is preferable to satisfy Expression (4) below, and it is more preferable to satisfy Expression (4’) below. 7.0% in mass < P(Bk) < 10.0% in mass...Expression (4) 7.6% in mass < P(Bk) < 8.5% in mass...Expression (4' )
    [00068] with P(Bk) satisfying Expression (4‘), flush recovery is higher, and image density of black ink is higher.
    [00069] A concentration of the colored pigment in the colored ink [P(CL)] is not particularly restricted as long as it satisfies Expression (2), and can be appropriately selected according to the purpose. Despite this, it is preferable to satisfy Expression (5) below, and it is more preferable to satisfy Expression (5‘) below. 4.0% in mass < P(CL) < 9.0% in mass ... Expression (5) 5.0% in mass < P(CL) < 9.0% in mass ... Expression (5' )
    [00070] With P(CL) satisfying Expression (5’), discharge stability is superior, and color ink image density is superior.
    [00071] A relationship between the resin coated carbon black particles, the surfactant treated carbon black particles, the resin coated colored pigment particles and the surfactant treated colored pigment particles in the ink set is not particularly restricted as long as Expression (3) is satisfied, and can be appropriately selected according to the purpose. Despite this, it is preferable that Expression (3’) below is satisfied, and it is more preferable that Expression (6) below and Expression (7) below are simultaneously satisfied. 0.01 < [R(CL) / S(CL)] < [R(Bk) / S(Bk)] < 100... Expression (3') 0.02 < [R(CL) / S(CL) )] < 1.00 ... Expression (6) 1.00 < [R(Bk) / S(Bk)] < 10.00 ... Expression (7)
    [00072] Additionally, it is especially preferable that Expression (6‘) below and Expression (7‘) below are simultaneously satisfied. 0.05 < [R(CL) / S(CL)] < 0.50 ... Expression (6') 2.00 < [R(Bk) / S(Bk)] < 8.00 ... Expression (7')
    [00073] With Expression (6‘) and Expression (7‘) simultaneously satisfied, image density and discharge stability are higher. water soluble organic solvent
    [00074] Black ink and colored ink use water as a medium, and a water-soluble organic solvent is preferably included for the purposes of preventing ink drying (as a wetting agent) and improving pigment dispersion stability.
    [00075] The water-soluble organic solvent is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, it is preferably a polyhydric alcohol, which has an equilibrium blend content in an environment having a temperature of 23°C and a relative humidity of 80% of 40% by mass or greater. Such polyhydric alcohol is not particularly restricted, and may be appropriately selected according to the purpose. Notwithstanding this, a wetting agent A having a boiling point at a normal pressure that exceeds 250°C and a wetting agent B having a boiling point at a normal pressure of 140°C or greater and less than 250°C are preferably used in combination.
    [00076] Examples of wetting agent A include 1,2,3-butanetriol, 1,2,4-butanetriol (boiling point: 190°C to 191°C/24hPa), glycerin (boiling point: 290°C) , diglycerin (boiling point: 270°C/20hPa), triethylene glycol (boiling point: 285°C), tetraethylene glycol (boiling point: 324°C to 330°C) and others.
    [00077] Examples of wetting agent B include diethylene glycol (boiling point: 245°C), 1,3-butanediol (boiling point: 203°C to 204°C) and others.
    [00078] Both wetting agent A and wetting agent B are hygroscopic materials having an equilibrium blend content of 40% by mass or greater in an environment having a temperature of 23°C and a relative humidity of 80%. Here, wetting agent B is relatively more evaporative than wetting agent A. When wetting agent A and wetting agent B are used in combination, a B/A ratio of wetting agent A and wetting agent B (mass ratio ) cannot be unambiguously determined as it depends on an excess amount of a wetting agent C described hereinafter and types and amounts of other additives such as penetration agent and others, but is preferably 10/90 to 90/10 .
    [00079] With respect to the equilibrium mixture content, the temperature and pressure in a desiccator was maintained at a temperature of 23±1°C and a relative humidity of 80±3% using a saturated aqueous solution of potassium chloride, a dish in which 1 g of each water-soluble organic solvent was weighed was stored in this desiccator, and the equilibrium mixture content could be obtained from a saturated mixture content.
    [00080] Saturated mix content (%) = (mix content absorbed by water-soluble organic solvent / water-soluble organic solvent) x 100
    [00081] In black ink and colored ink, other than a wetting agent A and wetting agent B, partially in place of wetting agent A and wetting agent B, or in addition to wetting agent A and wetting agent B, a wetting agent C other than wetting agent A and wetting agent B can be used in combination as needed.
    [00082] Examples of wetting agent C include polyhydric alcohol other than wetting agent A and wetting agent B, polyhydric alcohol alkyl ethers, polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, sulfur-containing compounds, propylene carbonate, ethylene carbonate, other wetting agents and others.
    [00083] Examples of the polyhydric alcohol include dipropylene glycol (boiling point: 232°C), 1,5-pentanediol (boiling point: 242°C), 3-methyl-1,3-butanediol (boiling point: 203°C). °C), propylene glycol (boiling point: 187°C), 2-methyl-2,4-pentanediol (boiling point: 197°C), ethylene glycol (boiling point: 196°C to 198°C) , tripropylene glycol (boiling point: 267°C), hexylene glycol (boiling point: 197°C), polyethylene glycol (viscous liquid to solid), polypropylene glycol (boiling point: 187°C), 1,6- hexanediol (boiling point: 253°C to 260°C), 1,2,6-hexanetriol (boiling point: 178°C), trimethylolethane (solid; melting point 199°C to 201°C), trimethylolpropane ( solid; melting point: 61°C) and others.
    [00084] Examples of polyhydric alkyl alcohol ethers include ethylene glycol monoethyl ether (boiling point: 135°C), ethylene glycol monobutyl ether (boiling point: 171°C), diethylene glycol monomethyl ether (boiling point: 194° C), diethylene glycol monobutyl ether (boiling point: 231°C), ethylene glycol mono-2-ethylhexyl ether (boiling point: 229°C), propylene glycol monoethyl ether (boiling point: 132°C) and others .
    [00085] A water-soluble organic solvent content in each of the black ink and color ink is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, it is preferably 10% by mass to 50% by mass. Fluorosurfactant and silicone surfactant
    [00086] The incorporation of surfactants in an ink decreases a surface tension thereof and accelerates a penetration into a recording medium such as paper after ink droplets land on the recording medium, and in this way, color diffusion and leakage can be reduced.
    [00087] Among the surfactants, a fluorosurfactant and a silicone surfactant are preferable, and the use of the fluorosurfactant and the silicone surfactant in combination is preferable in terms of superior image density, discharge stability and discharge recovery.
    [00088] The fluorosurfactant is not particularly restricted, and can be appropriately selected according to the purpose. Examples thereof include perfluoroalkyl sulfonate, perfluoroalkyl carboxylate, perfluoroalkyl phosphate ester, perfluoroalkyl ethylene oxide adduct, perfluoroalkyl betaine, perfluoroalkyl amine oxide compounds, polyoxyethylene perfluoroalkyl ether and others.
    [00089] As the fluorosurfactant, commercial products can be used. Examples of commercial products include SURFLON S-111, S-112, S-113, S121, S131, S132, S-141, S-144, S-145 (all manufactured by Asahi Glass Co., Ltd.), FLUORAD FC -93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431, FC-4430 (all manufactured by Sumitomo 3M Ltd.), MEGAFACE F-470, F -1405, F474 (manufactured by DIC Corporation), ZONYL FSN, FSN-100, FSO, FSO-100, FS-300 (all manufactured by DuPont Co.), EFTOP EF-351, 352, 801, 802 (all manufactured by Jemco Co., Ltd.), FT-250, 251 (all manufactured by Neos Company Ltd.), PF-151N, PF-136A, PF-156A (all manufactured by OMNOVA Solutions Inc.) and others. Among these, ZONYL FSO, FSO-100, FSN, FSN-100, FS-300 manufactured by DuPont Co. are preferable as they provide favorable print quality and storage stability.
    [00090] The silicone surfactant is not particularly restricted, and can be appropriately selected according to the purpose. Examples thereof include a modified polyether silicone compound and others.
    [00091] Examples of the modified polyether silicone compound include: a side chain type (side chain type) in which a polyether group is introduced into a polysiloxane side chain; a one-ended type that a polyether group is introduced at one end of the polysiloxane or a both ended type (ABA type) that a polyether group is introduced at both ends; a side chain on both ends type that a polyether group is introduced into a side chain and both ends of the polysiloxane; an ABn type in which a polysiloxane (A) with an introduction of the polyether group and a polysiloxane (B) without an introduction of the same are repeatedly bonded; a branched type in which a polyether group is introduced at one end of the branched polysiloxane; and others.
    [00092] As the polyether modified silicone compound, the side chain type (side chain type) that a polyether group is introduced into a polysiloxane side chain is preferable. The side chain type modified polyether silicone compound is not particularly restricted, and can be appropriately selected according to the purpose.
    [00093] Notwithstanding this, a silicone compound represented by General Formula (1) below is preferable as it functions to reduce a paint surface tension as well as it functions as an anti-adhesive agent to prevent the paint from sticking to a one-head nozzle plate. General Formula (1)

    [00094] Here, in the General Formula (1), l, m, n, p and q are natural numbers (excluding 0), satisfying l+m+n < 2,000 and p+q < 100.
    [00095] As the silicone surfactant, commercial products can be used. Examples of commercial products include KF-351A, KF-352A, KF-353 (the silicone surfactant represented by General Formula (1)), KF-354L, KF-355A, KF-615A, KF-945, KF-618, KF-6011, KF-6015, KF-6004 (all manufactured by Shin-Etsu Chemical Co., Ltd.), SF-3771, SF-8427, SF-8428, SH-3749, SH-8400, FZ-2101, FZ-2104, FZ-2118, FZ-2203, FZ-2207, L-7604 (all manufactured by Dow Corning Toray Co., Ltd.), BYK-345, BYK-346, BYK-348 (all manufactured by BYK Japan KK) and others.
    [00096] A content of the fluorosurfactant in each of the black ink and color ink is not particularly restricted, it may be appropriately selected according to the purpose. Despite this, it is preferably 0.1% by mass to 3.0% by mass, and more preferably 0.3% by mass to 1.0% by mass. Content being in the most preferable range is advantageous in view of higher image density and flush recovery.
    [00097] A silicone surfactant content in each of the black ink and color ink is not particularly restricted, it can be appropriately selected according to the purpose. Despite this, it is preferably 0.05% by mass to 0.3% by mass. The content being in the preferable range is advantageous in view of superior discharge stability. Other components
    [00098] Examples of the other components include a defoamer, a pH adjuster, an antiseptic and fungicide, a rust inhibitor, an antioxidant, an ultraviolet absorber and others.
    [00099] Examples of the defoamer include a silicone defoamer, a polyether defoamer, a fatty acid ester defoamer, and others.
    [000100] The pH adjuster is not particularly restricted as long as it can adjust a pH to 7 or higher, and can be appropriately selected according to the purpose. Examples thereof include diethanolamine, triethanolamine, lithium carbonate, sodium carbonate, potassium carbonate, ammonium hydroxide, lithium hydroxide, sodium hydroxide, potassium hydroxide and others.
    [000101] Examples of the antiseptic and fungicide include 1,2-benzisothiazolin-3-one, sodium dehydroacetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, sodium benzoate, sodium pentachlorophenol and others.
    [000102] Examples of the rust inhibitor include acid sulfite, sodium thiosulfate, ammonium thiodiglycollate, diisopropylammonium nitrite, pentaerythritol tetranitrate, nitrous acid dicyclohexylammonium salt and others.
    [000103] Examples of the antioxidant include phenol-based antioxidants (which include phenol-based hindered antioxidants), amine-based antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, and others.
    [000104] Examples of the ultraviolet absorber include oxybenzone, phenyl salicylate, para-aminobenzoic acid ester and others. paint viscosity
    [000105] A viscosity of black ink and color ink is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, the viscosity at 25°C is preferably 5.0mPa^s to 12.0mPa^s. Viscosity can be measured using, for example, a viscometer, RE80L, manufactured by Toki Sangyo Co., Ltd. (Inkjet Recording Method and Inkjet Recording Apparatus)
    [000106] An ink jet recording method of the present invention includes an ink spraying step preferably includes a suction generation step and a suck and cover step, and further includes other steps as needed.
    [000107] An ink jet recording apparatus of the present invention includes an ink spraying unit, preferably includes a suction generating unit and the suck and cover unit, and further includes other units as required.
    [000108] The inkjet recording method can be favorably performed by the inkjet recording apparatus; the paint spraying step can be favorably performed by the paint spraying unit; the suction generation step can be favorably performed by the suction generation unit; the suck and coat step can be favorably performed by the suck and coat unit; the other steps can be favorably carried out by the other units. <Paint spraying step and paint spraying unit>
    [000109] The paint spraying step is not particularly restricted as long as it is a step to form an image by applying a stimulus to each paint in the paint assembly of the present invention and spraying the paint. It can be appropriately selected according to the purpose, and it can be carried out using the paint spray unit, for example.
    [000110] The paint spraying unit is not particularly restricted as long as it is a unit to form an image by applying a stimulus to each paint in the paint assembly of the present invention and spraying the paint. It can be appropriately selected according to the purpose, and examples of it include a continuous injection type, an on-demand type and others. Examples of the on-demand type include a piezo system, a thermal system, an electrostatic system, and others. Among these, the piezo system and the thermal system are particularly preferable.
    [000111] Specifically, the spray paint unit preferably does not include a liquid chamber, a fluid resistance portion, a diaphragm, a nozzle member and the like, and it is preferable that at least a part of the liquid chamber, the fluid resistance portion, the diaphragm and the nozzle member are formed of a material that includes silicon or nickel, or both thereof.
    [000112] Furthermore, the inkjet nozzle has a nozzle diameter of preferably 30μm or less, and preferably 1μm to 20μm. <Suction generation step and suction generation unit>
    [000113] A suction generation step is not particularly restricted as long as it is a step to generate suction to suck a paint into nozzles in a suck and coat step, and can be appropriately selected according to the purpose. For example, it can be performed by the suction generating unit.
    [000114] A suction generating unit is not particularly restricted as long as it is a unit to generate suction to suck a paint into nozzles in the suction and coating unit, and can be appropriately selected according to the purpose. Examples of it include the suction pump and others. <Suck and cover step and suck and cover unit>
    [000115] A sucking and coating step is not particularly restricted as long as it is a step of coating a recording head that includes a plurality of nozzle arrangements, each including a plurality of nozzles, and sucking an ink into the nozzles, and can be appropriately selected according to the purpose. For example, it can be performed by the suck and cover unit.
    [000116] A suck and cover unit is not particularly restricted as long as it is a unit for covering a recording head that includes a plurality of nozzle arrangements, each including a plurality of nozzles, and sucking an ink into the nozzles, and can be appropriately selected according to the purpose. Examples of it include a suction cap and others. <Other steps and other units>
    [000117] Examples of the other steps include a stimulus generation step, a control step, and others.
    [000118] Examples of the other units include a stimulus generating unit, a control unit and others. Stimulus generation stage and stimulus generation unit
    [000119] The stimulus generation step is not particularly restricted since it is a step to generate a stimulus to spray paint, and can be appropriately selected according to the purpose. For example, it can be performed by the stimulus generation unit.
    [000120] Examples of the stimulus generating unit include a heating device, a pressurizing device, a piezoelectric element, a vibration generator, an ultrasonic oscillator, a light and others, and Specific examples thereof include: a piezo actuator such as the piezoelectric element and others; a thermal actuator which makes use of a phase change by boiling a liquid film using an electrothermal converting element such as a heating resistor and others; a memory and shape alloy actuator which makes use of changes in a metal phase due to temperature changes; and an electrostatic actuator which makes use of an electrostatic force; and others.
    [000121] The stimulus is not particularly restricted, and can be appropriately selected according to the purpose. Examples of it include heat (temperature), pressure, vibration, light and others. These can be used alone or in combination of two or more. Among these, heat and pressure are preferable.
    [000122] A paint spray aspect is not particularly restricted, and it varies depending on stimulus types and others. As an exemplary method, in a case where the stimulus is “heat”, a thermal energy corresponding to a recording signal is applied to ink in the recording head using, for example, a thermal head and others; in this way, air bubbles are generated by the thermal energy in the ink, and by the pressure of the air bubbles, the ink is discharged and blasted from the nozzle holes of the recording head as liquid droplets. Also, in a case where the stimulus is "pressure", for example, a voltage is applied to a piezoelectric element connected in a position called a pressure chamber located in an ink flow path in the recording head, which deflects the piezoelectric element and reduces a pressure chamber volume, and in this way the ink is discharged and blasted from the nozzle holes of the recording head as liquid droplets.
    [000123] With regard to the liquid droplets of the ink being drained, a size of the same is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, it is preferably 3pL to 40pL. A velocity of a discharge jet thereof is preferably 5m/s to 20m/s, a driving frequency thereof is preferably 1kHz or greater, and a resolution thereof is preferably 300dpi or greater. Control step and control unit
    [000124] A control step is not particularly restricted as long as it is a step to control steps, and can be appropriately selected according to the purpose. It can be performed by the control unit, for example.
    [000125] The control unit is not particularly restricted as long as it is a unit to control steps, and can be appropriately selected according to the purpose. Examples of it include devices such as a sequencer, a computer and others.
    [000126] The ink jet recording apparatus may include a maintenance/recovery apparatus.
    [000127] The maintenance/recovery apparatus includes: at least one suction and cover unit (suction cover) which covers the recording head and which communicates with the suction generating unit; and at least one non-sucking and covering unit (hydration cap) which covers the recording head and which does not communicate with the suction generating unit, and it additionally includes other units as required. As described, the inclusion of the suction cap and hydration cap reduces the amount of ink spent for a maintenance operation to ensure reliability compared to a configuration where all caps are suction caps, and time and time avoidance is possible. of the spent ink for the maintenance operation being wasted.
    [000128] The maintenance/recovery apparatus is not particularly restricted, and can be appropriately selected according to the purpose. Despite this, for example, the one disclosed in JP-A No. 2005-170035 and others can be used.
    [000129] Hereinafter, an example of the ink jet recording method of the present invention and the ink jet recording apparatus of the present invention is explained using the drawings.
    [000130] Here, FIG. 1 and FIG. 2 are schematic plan views of the recording head as viewed from a nozzle surface. FIG. 1 illustrates a two-head type composed of a first head (left) and a second head (right). FIG. 2 illustrates a four-head type composed of a first head, a second head, a third head and a fourth head which are arranged from left to right. In FIG. 1 and in FIG. 2, “A” and “B” denote arrangement A and arrangement B, respectively.
    [000131] In the two-head type, both the first head and the second head are covered with the suck and cover unit (suction cap) in communication with a suction generating unit, and the other is covered with a suction unit. do not suck and cover (hydration cap) not in communication with the suction generating unit. In the example of FIG. 1, the first head is covered with the suction cap, and the second head is covered with the hydration cap.
    [000132] In the four-head type, at least any one of the first head to the fourth head is covered with the suck and cover unit (suction cap) in communication with a suction generating unit, and the rest is (are ) covered with a non-suck and cover unit (hydration cap) not in communication with the suction generation unit. In the example of FIG. 2, the first head is covered with the suction cap, and the second, third and fourth heads are covered with the hydration cap.
    [000133] In the present invention, in any two-head type and four-head type, any nozzle arrangement of arrangement A and arrangement B in at least one head discharges a pigment ink that includes carbon black, and the another arrangement discharges a non-black colored ink.
    [000134] Here, in the two-head type of FIG. 1, for color recording, it is necessary to fill yellow (Y), cyan (C), magenta (M) and black (Bk) inks respectively into 4 nozzle arrangements.
    [000135] Here, an example of the ink jet recording apparatus of the present invention which includes the maintenance/recovery apparatus is explained with reference to FIG. 3. Here, FIG. 3 is a perspective diagram of the ink jet recording apparatus as viewed from a front side.
    [000136] This inkjet recording apparatus is equipped with: an apparatus main body 1; a paper feed tray 2 for loading paper mounted on the main body of apparatus 1; and a paper discharge tray 3 for storing sheets having an image engraved (formed) thereon mounted on the apparatus main body 1. Additionally, the apparatus main body 1 includes, on one side of a front surface 4, a section of cartridge loading section 6 which protrudes forward from the front surface and is smaller than a top surface 5, and on an upper surface of this cartridge loading section 6, an operating portion 7 such as keys of operation, indicators and others are arranged. Cartridge loading section 6 includes main tanks (hereafter referred to as "ink cartridges") 10 as tanks for storing liquid as liquid supplementation means are interchangeably mounted, and also includes a front cover 8 which can be opened and closed.
    [000137] The following is the mechanical section of the inkjet recording apparatus of FIG. 3 is explained with reference to FIG. 4 and FIG. 5. Here, FIG. 4 is a schematic configuration diagram for explaining an overall mechanical section configuration, and FIG. 5 is a plan view explaining an essential portion of the mechanical section.
    [000138] A carriage 33 is slidably held in a main scanning direction by a guide rod 31 and a support 32 as guide members held between left and right side plates 21A, 21B constituting a frame 21, and moves and scans by a main scan engine not shown in an arrow direction in FIG. 5 (car scan direction: main scan direction).
    [000139] The plurality of recording heads 34 composed of ink jet heads while the liquid droplet discharge heads for discharging liquid ink droplets (ink droplets) are arranged on this carriage 33 in a direction in which a plurality of nozzles intersects the main scanning direction and mounted with an ink droplet discharge direction downward. Here, the recording heads 34 are composed of, for example: a recording head 34y for discharging yellow liquid droplets (Y); a 34m recording head for discharging magenta (M) liquid droplets; a recording head 34C for discharging droplets of cyan liquid (C); a 34k recording head for discharging black liquid droplets (Bk). Here, there is no distinction in terms of color when they are called “34 recording heads”. Here, the head configuration is not limited to these examples, and the head can be configured using one or more recording heads that include one or more nozzle arrays which discharge liquid droplets of one or more colors.
    [000140] As the liquid droplet discharge head which constitutes the recording head 34, those equipped with a piezo actuator such as the piezoelectric element and others, a thermal actuator which makes use of a phase change by boiling film of a liquid that uses an electrothermal conversion element such as a heating resistor and others, a shape and memory alloy actuator which makes use of changes in a metal phase due to temperature changes, an electrostatic actuator which makes use of of an electrostatic force and others like a power generating unit to discharge liquid droplets can be used.
    [000141] Further, 35y, 35m, 35c, 35k subtanks (these are simply called "35 subtanks" where no color distinction is required) are mounted on carriage 33 to supply inks of the respective colors to the respective recording heads 34 For these sub-tanks 35, inks are supplied from ink cartridges 10 (these are called “10y, 10m, 10c, 10k ink cartridges” where their colors are distinguished) described above through supply tubes. ink 37 of the respective colors.
    [000142] Here, ink cartridges 10 are, as illustrated in FIG. 5, contained in a cartridge loading section 6, and this cartridge loading section 6 is equipped with a supply pump unit 23 for pumping an ink into an ink cartridge 10. Further, ink supply tubes 37 are held fixed to a back plate 21C constituting the frame 21 with a detent 25 on the main body side between the ink cartridge loading section 6 and the sub-tanks 35. Additionally, they are also fixed to the carriage 33 with a fixing rib 26 .
    [000143] Meanwhile, like a paper feed section to feed sheets 42 loaded into a paper stacking unit (back plate) 41 of paper feed tray 2, there is a separation block 44 which separates and feeds the sheets 42 one by one from the paper stacking unit 41 and which faces a paper feed roller 43 and is made of a material having a large coefficient of friction, and this separating block 44 is biased towards the paper feed roller 43.
    [000144] Further, as a conveyor section for transporting the sheet 42 fed from this paper feed section on an underside of the recording heads 34, the apparatus is equipped with: a conveyor belt 51 for conveying the sheets 42 through electrostatic absorption of it; a counter roller 52 for transporting the sheet 42 fed from the paper feed section through a guide 45 by sandwiching it with the conveyor belt 51; a conveyor guide 53 for diverging by approximately 90° the sheet 42 sent in a substantially vertical and upward direction in order to follow the conveyor belt 51; and a front pressure roller 55 biased towards the conveyor belt 51 by a pressure member 54. Further, the apparatus is equipped with a loading roller 56 as a loading unit for loading a surface of the conveyor belt 51.
    [000145] Here, the conveyor belt 51 is an endless belt, stretched between a conveyor roller 57 and a tension roller 58 so that it is configured to rotate in a conveyor belt direction in FIG. 5. The loading roller 56 is arranged to contact a surface layer of the conveyor belt 51 and to rotate through the rotation of the conveyor belt 51 and place 2.5N at each end of an axis thereof as a force of pressurization.
    [000146] Further, a guide member 61 is correspondingly arranged to a print region by the recording heads 34 behind the conveyor belt 51. A top surface of this guide member 61 is protruding towards one side of the recording heads. engraving 34 with respect to a tangent line of the two (2) rollers (the conveyor roller 57 and the tension roller 58) which support the conveyor belt 51. In this way, the conveyor belt 51 is lifted and guided on the surface of the top guide member 61 in the print region, and in this way, high precision leveling is maintained.
    [000147] Additionally, as a paper unloading unit for unloading the sheets 42 with recording by the recording heads 34, the apparatus is equipped with: a separating claw 71 for separating the sheet 42 from the conveyor belt 51; a paper unloading roller 72 and a paper unloading roller 73; and a paper unloading tray 3 below the paper unloading roller 72. Here, a height from the paper unloading tray 3 to the position between the paper unloading roller 72 and the paper unloading roller 73 is relatively large so an increase in the amount of sheets to be stored in the paper dump tray 3.
    [000148] In addition, a double-sided paper feed unit 81 is detachably attached to a rear part of the apparatus main body 1. This double-sided paper feed unit 81 captures and inverts the returned sheet 42 by a rotating in a reverse direction of the conveyor belt 51, and feeds the sheet again between a counter roller 52 and the conveyor belt 51. Further, a manual paper feed unit 82 is arranged on a top surface of this feed unit. two-sided paper 81.
    [000149] Additionally, as illustrated in FIG. 5, a maintenance/recovery apparatus (hereafter, it may be referred to as "subsystem") 91 is arranged in a non-printing region on one side of the scan direction of carriage 33 to maintain and recover a nozzle condition of the recording heads 34.
    [000150] This subsystem 91 is equipped with: cap members (hereafter, they are also referred to as "caps") 92 for capping respective nozzle surfaces of the recording heads 34; a sweeper blade 93 as a blade member for cleaning the nozzle surfaces; a pattern discharge receiver 94 for receiving liquid droplets during pattern discharge which liquid droplets which do not contribute to recording are discharged to the discharge of a viscous ink, and a sweeping wiper (not shown) as a member wiper integrally formed with this empty discharge receiver 94 to remove an ink adhered to the sweeper blade 93; a cleaning roller 96 which constitutes a cleaning means for pressing the sweeping blade 93 to one side of the sweeping cleaner in cleaning the sweeping blade 93; and others.
    [000151] Further, as illustrated in FIG. 5, an empty discharge receiver 98 is arranged in the non-printing region on the other side of the scanning direction of carriage 33 to receive liquid droplets during pattern discharge wherein liquid droplets which do not contribute to a recording are discharged to discharge a viscous ink during recording, and this empty discharge receiver 98 is equipped with openings 99 along a nozzle direction arrangement of recording heads 34.
    [000152] In the inkjet recording apparatus as configured above, the sheets 42 are separated and fed one by one from the paper feed tray 2. The sheet 42 fed in a substantially vertical direction and upwards is guided by the guide 45 is conveyed by being sandwiched between conveyor belt 51 and counter roller 52, and one end thereof is further guided by conveyor guide 53. It is pressed onto conveyor belt 51 by front pressure roller 55, and a direction of transport of the same is diverged by approximately 90°.
    [000153] At this time, a positive energy and a negative energy are alternately and repeatedly applied, i.e. an alternating voltage is applied, to the charging roller 56 from a high voltage power source by a control circuit not shown , and the conveyor belt 51 achieves an alternating charged voltage pattern; that is, it is alternatively loaded with the positive and negative forming strips with a predetermined width in a subscan direction as a rotational direction thereof. When the sheet 42 is fed onto this charged conveyor belt 51 with alternating positive and negative charges, the sheet 42 is electrostatically absorbed onto the conveyor belt 51, and the sheet 42 is conveyed in the subscan direction by a rotary movement of the conveyor belt 51 When the recording heads 34 are driven in correspondence with an image signal while the carriage 33 is moved, the recording heads discharge ink droplets onto the still sheet 42 to record a line. Then, sheet 42 is transported a predetermined distance, and the next line is recorded. When a recording end signal or a signal that a trailing end of the sheet 42 has reached a recording region is received, the recording operation is terminated, and the sheet 42 is discharged into the paper discharge tray 3.
    [000154] Further, while waiting for printing (engraving), carriage 33 is moved to a side of subsystem 91, where recording heads 34 are capped with cap members 92 to keep the nozzles wet, and thus failure discharge due to ink drying is avoided. In addition, a recovery operation is performed in which the viscous ink or air bubbles are discharged by suction of the inks from the nozzles with the cap members 92 capping the recording heads 34 ("nozzle suction" or "head suction ”). Also, the pattern unload operation is performed by unloading a non-recording ink before recording or during recording. In this way, the stable discharge performance of the recording heads 34 is maintained.
    [000155] In the following, an overview of the configuration of subsystem 91 which includes a maintenance/recovery apparatus in the ink jet recording apparatus of the present invention is explained with reference to FIG. 6 to FIG. 8. Here, FIG. 6 is a schematic configuration diagram of the system, FIG. 7 is a rough schematic configuration diagram of the system, and FIG. 8 is an explanatory diagram on the right side of FIG. 6.
    [000156] For a frame (maintenance apparatus frame) 111 of this subsystem 91, two (2) lid holders 112A and 112B as a lid detent mechanism, a sweeper blade 93 as a sweeper member which includes a body elastic as a means of cleaning, and a carriage lock 115 are arranged, where each can be raised and lowered (movable vertically). In addition, an empty dump receiver 94 is arranged between the sweeper blade 93 and the cap keeper 112A, and to clean the sweeper blade 93, a sweeper wiper 118 as a cleaning means which includes a cleaning roller 96 as a wiper member for biasing the sweeper blade 93 from the outside of the frame 111 to a side of the sweeper wiper 95 as an empty dump receiver cleaning member 94 is pivotally held.
    [000157] The 112A and 112B lid holders (they are interchangeably referred to as "112 lid holders") respectively hold two (2) lids 92a and 92b, and lids 92c and 92d (they are interchangeably called "92 lids") to cap the nozzle surface of the two (2) recording heads 34.
    [000158] Here, a pipe pump (suction pump) 120 as a suction means is connected through a flexible tube 119 to the cap 92a held by cap keeper 112A on a side closer to the printing region, and the pipe pump 120 is not connected to other covers 92b, 92c, 92d. That is, only the cap 92a is considered to be a suction (recovery) and the hydration cap (hereafter, it may be referred to as "suction cap"), and the other caps 92b, 92c, 92d are all considered to be hydration caps. Thus, when a recording heads 34 recovery operation is performed, the recording heads 34 for the recovery operation are selectively moved to a location where it can be capped by the suction cap 92a.
    [000159] Further, a camshaft 121 rotatably supported by the frame 111 is arranged below these cap detents 112A and 112B. This camshaft 121 is equipped with: cover cams 122A and 122B for raising and lowering cover detents 112A, 112B; a sweep cam 124 for raising and lowering the sweep blade 93; a carriage lock cam 125 for raising and lowering the carriage lock 115 via a carriage lock arm 117; a roller 126 as a rotating body which is the model discharge support member on which liquid droplets from the model discharge land in the empty discharge receiver 94; and a wiper cam 128 for oscillating sweep wiper 118.
    [000160] Here, covers 92 are raised and lowered by cover cams 122A, 122B. The sweeper blade 93 is raised and lowered by the sweeping cam 124. The sweeper wiper 118 proceeds when the sweeper blade 93 is being lowered, while it is sandwiched between the wiper roller 96 of this sweeper wiper 118 and the sweeper cleaner. sweep 95 from the empty discharge receiver 94, and an ink adhered to the sweeper blade 93 is scraped off at the empty discharge receiver 94.
    [000161] Carriage lock 115 is biased upward (locking direction) by a compression spring not shown, and is raised and lowered via a carriage lock arm 117 actuated by carriage lock cam 125.
    [000162] Then, to rotationally drive the pipe pump 120 and the camshaft 121, the rotation of a motor 131 is transmitted to a motor gear 132 fixed to a motor shaft 131a, and the motor gear 132 engages a pump gear 133 fixed to a pump shaft 120a of pipe pump 120. Additionally, an idler gear 134 formed with the pump gear 133 engages an idler gear 136 having a one-way clutch 137 through an idler gear 135, a idler gear 138 which shaft is the same as idler gear shaft 136 engages a cam gear 140 attached to camshaft 121 through idler gear 139. Here an idler shaft 141 ie a rotary idler shaft of idler gear 136,138 having gear 137 is rotatably held by frame 111.
    [000163] Further, a cam for home position sensor 142 is arranged on cam shaft 121 to detect an home position. When the covers 92 go to the lower part by a home position sensor (not shown) arranged in this subsystem 91, a home position lever (not shown) is operated, the sensor is in an open state, and a position motor 131 (other than pump 120) is detected. Here, when the power source is turned on, it moves up and down regardless of the position of the caps 92 (cap holders 112), and the position is not detected until it starts moving. After the home position (in the lifting means) of the covers 92 is detected, it moves to the lower end by moving a predetermined distance. Next, the carriage moves from side to side and returns to a capped position after a position detection, and the recording heads 34 are capped.
    [000164] In the following, a detent mechanism and a lifting mechanism (mechanism that moves vertically) of the covers 92 are explained in detail with reference to FIG. 9. Here, FIG. 9 is a side view of the mechanical section that lifts and secures the cover.
    [000165] A cap detent 112A as a cap detent mechanism includes: a detent 151 that holds a cap 92a and a cap 92b (these may also be collectively referred to as "caps 92A") in a vertically movable manner; springs 152 biasing upwardly on caps 92A interposed between the bottom of caps 92A and the bottom surface of detent 151; and a slide 153 which holds the detent 151 in a movable manner in a longitudinal direction (in a direction of an arrangement of the nozzles of the recording heads 34).
    [000166] The covers 92A are mounted on the detent 151 in a vertically movable manner by inserting guide pins 150a at both ends thereof to guide the slots (not shown) of the detent 151 in a vertically movable manner and by inserting shafts of guides 150b arranged on the bottom surface thereof for the detent 151 in a vertically movable manner. Springs 152 interposed between caps 92A and cap keeper 151 upward bias caps 92a, 92b (in a direction in which they press towards the nozzle surface when they are capping).
    [000167] With respect to slide 153, slidingly adjusting guide pins 154, 155 allocated at front and rear ends thereof to guide slots 156 formed in frame 111, slide 153, detent 151 and covers 92A as a whole are set to move vertically.
    [000168] Then, a cam pin 157 disposed on the bottom surface of the slide 153 is fitted to a cam groove (not shown) of a cover cam 122A, and by rotation of the cover cam 122A which moves with the rotation of camshaft 121 to transmit rotation of engine 131, slide 153, detent 151 and cover 92A move vertically.
    [000169] Additionally, a tube 119 is inserted through the slide 153 and the detent 151, rotated downward from the central position of the cap with respect to a transverse direction of the cap 92a and connected to the suction cap 92a.
    [000170] Here, a 112B cap keeper which holds 92c, 92d caps (these may also be collectively referred to as "92B caps") and a configuration for vertical movement thereof is similar to the above, and an explanation of the same is omitted . Here, a tube 119 is not connected to caps 92c, 92d. Thus, the configuration is such that the drive of the engine 131 as a drive source rotates the camshaft 121 as a shaft and that the rotation of this camshaft 121 rotates the cams 122A, 122B attached to the camshaft 121 and moves. vertically caps 92A and caps 92B. Examples
    [000171] Hereinafter, the present invention is further described in detail with reference to Examples, which however should not be interpreted as limiting the scope of the present invention. “Part” represents “bulk parts” unless otherwise stated, and “%” represents “bulk%” unless stated differently. (Preparation Example 1) <Preparation of resin coated carbon black particle dispersion>
    [000172] A 1L flask equipped with a mechanical stirrer, a thermometer, a nitrogen gas inlet tube, a reflux tube and a dropping funnel was sufficiently purged with a nitrogen gas and then charged with 11.2g of styrene , 2.8g acrylic acid, 12.0g lauryl methacrylate, 4.0g polyethylene glycol methacrylate (BLEMMER PE-90, manufactured by NOF Corporation), 4.0g styrene macromer (AS-6, manufactured by Toagosei Co. , Ltd.), and 0.4g of mercaptoethanol and heated to 65°C. Then a mixed solution of 100.8g of styrene, 25.2g of acrylic acid, 108.0g of lauryl methacrylate, 36.0g of polyethylene glycol methacrylate (BLEMMER PE-90, manufactured by NOF Corporation), 60.0g of hydroxyethylmethacrylate , 36.0g of styrene macromer (AS-6, manufactured by Toagosei Co., Ltd.), 3.6g of mercaptoethanol, 2.4g of azobisdimethylvaleronitrile, and 18g of methyl ethyl ketone were added dropwise into the flask for 2 ,5 hours. After the end of the dropwise addition, a mixed solvent of 0.8g of azobisdimethylvaleronitrile and 18g of methyl ethyl ketone was added dropwise into the flask over 0.5 hours. It was aged at 65°C for 1 hour, followed by an addition of 0.8g of azobisdimethylvaleronitrile, and further aged for 1 hour. After the end of the reaction, 364g of methyl ethyl ketone was added to the flask, and 800g of a polymer solution having a concentration of 50% was obtained. Next, a part of the polymer solution was dried and measured by gel permeation chromatography (standard: polystyrene; solvent: tetrahydrofuran), and a mass average molecular weight of the same was 15,000.
    [000173] So, 28g of the polymer solution thus obtained, 26g of carbon black (NIPEX160, manufactured by Degussa), 13.6g of 1 mol/L potassium hydroxide solution, 20g of methyl ethyl ketone, and 30g of water of ion exchange were sufficiently agitated. It was then kneaded 20 times using a three-roll mill (NR-84A, manufactured by Noritake Co., Ltd.). A slurry obtained was added with 200g of ion exchange water and sufficiently stirred, and then methyl ethyl ketone and a part of water were distilled using an evaporator. In this way, dispersion of resin coated carbon black particles having a pigment concentration of 13% was obtained. (Preparation Example 2) Preparation of surfactant treated carbon black particle dispersion> <<Composition>> Carbon black 175 parts (NIPEX160, manufactured by Degussa; BET specific surface area: 150m2/g, primary particle diameter medium: 20nm, pH 4.0; DBP oil absorption: 620g/100g) Sodium naphthalene sulfonate formalin condensed 175 parts (PIONIN A-45-PN, manufactured by Takemoto Oil &Fat Co., Ltd.; total dimer content , naphthalenesulfonate trimers and tetramers = 50%) Distilled water 650 parts
    [000174] A mixture of the above composition was pre-mixed, and a mixed slurry (a) was prepared. This was circulated and dispersed at a circumferential speed of 10m/s and a liquid temperature of 10°C for 3 minutes in a disk-type media mill (DMR, manufactured by Ashizawa Finetech Ltd.) with 0.05 zirconia beads mm with a packing rate of 55% by volume, coarse particles were centrifuged by a centrifuge (Model-7700, manufactured by Kubota Corporation), and a dispersion of surfactant treated carbon black particles having a pigment concentration of 13% was gotten. (Example of Preparation 3) <Preparation of Resin Coated Magenta Pigment Particle Dispersion>
    [000175] A dispersion of resin coated magenta pigment particles having a pigment concentration of 13% was obtained in the same manner as in Preparation Example 1 except that carbon black as a pigment in Preparation Example 1 was charged to CI Pigment red 122 (CROMOPHTAL Jet Magenta DMQ, manufactured by BASF).
    [000176] The obtained dispersion of resin coated magenta pigment particles was measured using a particle size distribution measuring apparatus (MICROTRAC UPA, manufactured by Nikkiso Co., Ltd.), and an average particle diameter (D50% ) of the same was 127nm. (Preparation Example 4) <Preparation of dispersion of surfactant treated magenta pigment particles> <<Composition>> Pigment red 122 24 parts (TONER MAGENTA EO02, manufactured by Clariant (Japan) K.K.)
    [000177] A 10% aqueous solution of a compound represented by the following structural formula 120 parts

    [000178] A mixture (A) of the above composition was placed in a 500 ml beaker and stirred for 3 hours with an addition of TEFLON (trademark) coated stir bar. Next, the mixture (A) which was processed with this mixture was subjected to a dispersion process for 8 hours in a sand mill (batch bench type sand mill, manufactured by Kanpe Hapio Co., Ltd.) using zirconia beads having a diameter of 0.3mm, and a dispersion of surfactant treated magenta pigment particles having a pigment concentration of 13% was obtained.
    [000179] The obtained dispersion of surfactant treated magenta pigment particles was measured using a particle size distribution measuring apparatus (MICROTRAC UPA, manufactured by Nikkiso Co., Ltd.), and an average particle diameter (D50% ) of the same was 97nm. (Preparation Example 5) <Preparation of resin coated cyan pigment particles dispersion>
    [000180] Dispersion of resin coated cyan pigment particles having a pigment concentration of 13% was obtained in the same manner as Preparation Example 1 except that carbon black as a pigment in Preparation Example 1 was changed to a copper phthalocyanine pigment (CHROMOFINE BLUE A-220JC, CI Blue Pigment 15:3, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.).
    [000181] The obtained dispersion of resin coated cyan pigment particles was measured using a particle size distribution measuring apparatus (MICROTRAC UPA, manufactured by Nikkiso Co., Ltd.), and an average particle diameter (D50% ) of the same was 93nm. (Preparation Example 6) <Preparation of dispersion of cyan pigment particles treated with surfactant>
    [000182] A dispersion of surfactant treated cyan pigment particles having a pigment concentration of 13% was obtained in the same manner as Preparation Example 4 except Pigment Red 122 (TONER MAGENTA EO02, manufactured by Clariant (Japan) KK) in Preparation Example 4 was changed to Pigment Blue 15:3 (LIONOL BLUE FG-7351, manufactured by Toyo Ink Co., Ltd.).
    [000183] The obtained dispersion of surfactant treated cyan pigment particles was measured using a particle size distribution measuring apparatus (MICROTRAC UPA, manufactured by Nikkiso Co., Ltd.), and an average particle diameter (D50% ) of the same was 97nm. (Preparation Example 7) <Preparation of resin coated yellow pigment particles dispersion>
    [000184] A dispersion of resin coated yellow pigment particles having a pigment concentration of 13% was obtained in the same manner as in Preparation Example 1 except that carbon black as a pigment in Preparation Example 1 was changed to CI Pigment Yellow 74 (Fast Yellow 531, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.).
    [000185] The obtained dispersion of resin coated yellow pigment particles was measured using a particle size distribution measuring apparatus (MICROTRAC UPA, manufactured by Nikkiso Co., Ltd.), and an average particle diameter (D50% ) of the same was 76nm. (Preparation Example 8) <Preparation of the dispersion of yellow pigment particles treated with surfactant>
    [000186] A dispersion of surfactant treated yellow pigment particles having a pigment concentration of 13% was obtained in the same manner as Preparation Example 4 except Pigment Red 122 (TONER MAGENTA EO02, manufactured by Clariant (Japan) KK) in Preparation Example 4 was changed to Pigment Yellow 138 (LIONOGEN YELLOW 1010, manufactured by Toyo Ink Co., Ltd.).
    [000187] The obtained dispersion of surfactant treated yellow pigment particles was measured using a particle size distribution measuring apparatus (MICROTRAC UPA, Manufactured by Nikkiso Co., Ltd.), and an average particle diameter (D50% ) was 70nm. <Preparation of recording ink>
    [000188] Embossing inks were manufactured by the following procedure. First, dispersions, water-soluble organic solvents (wetting agents), surfactants and water shown in Table 1-A through Table 3 below were mixed and stirred for 1 hour for uniform mixing. This dispersion liquid was subjected to pressure filtration on a polyvinylidene fluoride membrane filter having an average pore diameter of 5.0μm to remove coarse particles and dust, and the embossing ink from Table 1-A to Table 3 below have been prepared. In the tables, "equ." denotes "balance". Table 1-A

    Table 1-B
    Table 1-C
    Table 1-D

    Table 2-A

    Table 2-B

    Table 2-C
    Table 2-D

    Table 3


    [000189] The pigment dispersions and the surfactants in Table 1-A to Table 3 are as follows. * 1 Carbon black pigment dispersion having a pigment concentration of 13%, manufactured by Toyo Ink Co., Ltd. * 2 Polyoxyethylene perfluoroalkyl ether, having a solid content of 40%, manufactured by DuPont Co. * 3 Compound of modified polyether silicone, having a solids content of 100%, manufactured by Shin-Etsu Chemical Co., Ltd.
    [000190] Table 4-A below shows the carbon black concentration of the black inks as well as R(Bk), S(Bk) and R(Bk)/S(Bk).
    [000191] Table 4-B below shows the pigment concentrations of color inks as well as R(CL), S(CL) and R(CL)/S(CL). Table 4-A

    Table 4-B
    <Ink Set Print Evaluation>
    [000192] A print evaluation was carried out for the ink set of Examples 1 to 20 and Comparative Examples 1 to 10 shown in Table 5-1 and Table 5-2 below.
    [000193] It was performed using an inkjet printer (IPSIO GX3000, manufactured by Ricoh Company, Ltd.) by varying a drive voltage of a piezoelectric element so that an equal amount of an ink was discharged and a quantity like an ink has been adhered to a recording medium.
    [000194] The inkjet printer used for the evaluation was a two-head type printer, which includes 2 nozzle arrangements (nozzle arrangement A and nozzle arrangement B) per 1 head, and a suction cap was divided into each head. Thus, in this evaluation, inks in a set of two colors which were subjected to evaluation were filled into an identical head.
    [000195] Here, a RE80L viscometer, manufactured by Toki Sangyo Co., Ltd., was used to measure a viscosity of a paint, and a viscosity at 25°C was measured. Results are shown in Table 5-1 and Table 5-2.
    [000196] Also, P(Bk), [R(Bk) / S(Bk)], P(CL), [R(CL) / S(CL)], and [R(Bk) / S(Bk) ] - [R(CL) / S(CL)] are shown in Table 5-1 and Table 5-2. Table 5-1

    Table 5-2


    [000197] Assessments of “image density” and “discharge stability” were performed in an environment adjusted to an MM environment (25±0.5°C, 50±5%RH).
    [000198] Here, the evaluation of only “flush recovery” was performed in an environment adjusted to an HL environment (32±0.5°C, 15±5%RH).
    [000199] The valuation items and the valuation methods are therefore described below. <<Image Density>>
    [000200] A graphic including a solid black square character of 64 points of black and the respective colors, which was created using Microsoft Word 2003, was printed on high quality MYPAPER paper having a basis weight of 69.6g/m2, a sizing degree of 23.2 seconds and an air permeability of 21.0 seconds (manufactured by Ricoh Company, Ltd.). Then, the solid black square portion was subjected to calorimetry using X-Rite 938 (manufactured by X-Rite, Inc.), and an image density was evaluated. Currently, “quick - plain paper” mode has been selected by a print mode with a trigger included in the printer. Here, the image density of each color was determined based on the following evaluation criteria.[Assessment Criteria] A: Black OD value: 1.20 or greater Yellow: 0.75 or greater Magenta: 0.90 or greater Cyan: 1.00 or greater B: OD value Black: 1.10 or greater and less than 1.20 Yellow: 0.70 or greater and less than 0.75 Magenta: 0.80 or greater and less than than 0.90 Cyan: 0.90 or greater and less than 1.00 C: OD value Black: 1.00 or greater and less than 1.10 Yellow: 0.65 or greater and less than 0, 70 Magenta: 0.70 or greater and less than 0.80 Cyan: 0.80 or greater and less than 0.90 D: OD value Black: less than 1.00 Yellow: less than 0.65 Magenta: less than 0.70 Cyan: less than 0.80 <<Dump Recovery>>
    [000201] Each of the inks from Examples 1 to 20 and Comparative Examples 1 to 10 shown in Table 5-1 and Table 5-2 were filled in an inkjet printer and left to rest in an HL environment (32±0.5 °C, 15±5%RH) for 3 hours. Then, a full color nozzle check pattern was printed, and it was confirmed that there was no discharge failure such as dead pixels and deflection. Thereafter, it was additionally left to rest for 6 days as it was. After the rest ended, a sheet of a nozzle check pattern which includes a solid print portion was printed on high quality MYPAPER paper having a basis weight of 69.6g/m2, a sizing degree of 23.2 seconds and an air permeability of 21.0 seconds (manufactured by Ricoh Company, Ltd.), and it was confirmed whether or not there were dead pixels or deflection. If dead pixels or ink deflection were observed in the nozzle check pattern, a cleaning of the printer nozzles is performed as a return operation to normal printing, and the total number of the nozzles was evaluated. From the total number obtained, the discharge recovery of each ink was evaluated based on the following evaluation criteria. [Evaluation Criteria] A: The number of cleans was 0 to 1. B: The number of cleans was 2 or greater and less than 5. D: The number of cleans was 5 or greater. <<Discharge Stability>>
    [000202] Each of the inks from Examples 1 to 20 and Comparative Examples 1 to 10 shown in Table 5-1 and Table 5-2 has been filled into the inkjet printer, and a chart that includes solid patterns black, cyan, magenta, yellow and line with identical area and identical shape were continuously printed on 100 sheets of high quality MYPAPER paper having a basis weight of 69.6g/m2, a sizing degree of 23.2 seconds and an air permeability of 21.0 seconds (manufactured by Ricoh Company, Ltd.). During printing, if dead pixels or ink deflection were observed in the graph, a printer nozzle cleaning is performed as a fallback operation to normal printing, and the total number of the same was evaluated. From the total number obtained, the discharge stability of each ink set was evaluated based on the following Evaluation criteria. [Evaluation Criteria] A: The number of cleans was 0 to 1. B: The number of cleans was 2 or greater and less than 5. D: The number of cleans was 5 or greater. <<Global assessment>>
    [000203] Each ink set has been subjected to an overall assessment at 5 levels based on the following criteria. The results are shown in Table 6. [Assessment Criteria] 5: Image density, discharge recovery and discharge stability were all “A”. 4: Image Density, Dump Recovery and Dump Stability were all “B” or greater, and both Dump Recovery and Dump Stability were all “A”. 3: Image Density, Dump Recovery, and Dump Stability were all “B” or greater, and both Dump Recovery and Dump Stability were “A”. 2: Image Density, Dump Recovery and Dump Stability were all “B” or greater, and both Dump Recovery and Dump Stability were all “B”. 1: Any one of image density, flush recovery, and flush stability was “C” or “D”. Table 6


    Aspects of the present invention are as follows, for example. <1> An ink set, which includes: one black ink; and a colored ink, wherein the ink assembly is used in an ink jet recording apparatus, which includes: a recording head which includes a plurality of nozzle arrangements, each including a plurality of nozzles; and at least one sucker and cover unit that covers the recording head and communicates with a suction generating unit, wherein the black ink is supplied to one of the plurality of nozzle arrangements of the recording head, and the colored ink is provided for the other plurality of recording head nozzle arrangements, wherein the black ink includes: resin coated carbon black particles that include carbon black and a resin that exists on a surface of the carbon black; surfactant-treated carbon black particles that include carbon black and a surfactant that exists on a surface of carbon black; and water, where the color ink includes: resin-coated color pigment particles that include a color pigment and a resin that exists on a surface of the color pigment; surfactant-treated color pigment particles that include a color pigment and a surfactant that exists on a surface of the color pigment; and water, where the ink set satisfies Expression (1), Expression (2), and Expression (3) below: 5.0% by mass < P(Bk) < 12.0% by mass... Expression (1) 3.0% in mass < P(CL) < 10.0% in mass ... Expression (2) [R(CL) / S(CL)] < [R(Bk) / S(Bk )] ... Expression (3) where, in Expression (1), P(Bk) represents a concentration of carbon black in the black ink; in Expression (2), P(CL) represents a pigment concentration of the colored ink; in Expression (3), R(Bk) represents a mass ratio of carbon black in resin coated carbon black particles to carbon black in black ink, S(Bk) represents a mass ratio of carbon black in the surfactant treated carbon black particles to the carbon black in the black ink, R(CL) represents a mass ratio of the colored pigment in the resin coated colored pigment particles to the colored pigment in the colored ink, and S(CL) ) represents a mass ratio of the colored pigment in the colored pigment particles treated with surfactant to the colored pigment in the colored ink. <2> The ink set according to <1>, wherein the black ink and the color ink have a viscosity at 25°C of 5.0 mPa-s to 12.0 mPa-s. <3> The ink set according to any one of <1> to <2>, wherein the black ink and the color ink include a fluorosurfactant and a silicone surfactant. <4> The ink set according to any one of <1> to <3>, where the ink set satisfies Expression (4) and Expression (5) below: 7.1 % by mass < P(Bk) < 10.0% by mass ... Expression (4) 7.2 % by mass < P(CL) < 9.0% by mass ... Expression (5). <5> The ink set according to any one of <1> to <4>, where the ink set satisfies Expression (3') below: 0.01 < [R(CL) / S(CL) ] < [R(Bk) / S(Bk)] < 100 ... Expression (3'). <6> The ink set according to any one of <1> to <5>, where the ink set satisfies Expression (6) and Expression (7) below: 0.02 < [R(CL) / S(CL)] < 1.00 ... Expression (6) 1.00 < [R(Bk) / S(Bk)] < 10.00 ... Expression (7). <7> The ink set according to any one of <1> to <6>, wherein the black ink and the color ink include a water-soluble organic solvent. <8> An inkjet recording method, which includes: spraying an ink, in which a stimulus is applied to each ink in the ink set according to any one of <1> to <7> to spray the ink and to form an image.
    权利要求:
    Claims (7)
    [0001]
    1. Ink assembly used in inkjet recording apparatus comprising: a black ink; and a colored ink, wherein the ink jet recording apparatus comprises: a recording head (34) which comprises a plurality of nozzle arrangements, each comprising a plurality of nozzles; and at least one sucker and cover unit that covers the recording head and communicates with a suction generating unit, wherein the black ink is supplied to one of the plurality of nozzle arrangements of the recording head, and the colored ink is provided for the other plurality of recording head nozzle arrangements, wherein the black ink comprises: resin coated carbon black particles comprising carbon black and a resin existing on a surface of the carbon black; surfactant-treated carbon black particles comprising carbon black and a surfactant that exists on a surface of carbon black; and water, wherein the colored ink comprises: resin coated colored pigment particles comprising a colored pigment and a resin existing on a surface of the colored pigment; surfactant-treated colored pigment particles comprising a colored pigment and a surfactant that exists on a surface of the colored pigment; and water, characterized by the fact that the ink set satisfies Expression (1), Expression (2) and Expression (3) below: 5.0% by mass < P(Bk) < 12.0% by mass ... Expression (1) 3.0% by mass < P(CL) < 10.0% by mass ... Expression (2) [R(CL) / S(CL)] < [R(Bk) / S(Bk)] ... Expression (3) where, in Expression (1), P(Bk) represents a carbon black concentration of the black ink; in Expression (2), P(CL) represents a pigment concentration of the colored ink; in Expression (3), R(Bk) represents a mass ratio of carbon black in resin coated carbon black particles to carbon black in black ink, S(Bk) represents a mass ratio of carbon black in the surfactant treated carbon black particles to the carbon black in the black ink, R(CL) represents a mass ratio of the colored pigment in the resin coated colored pigment particles to the colored pigment in the colored ink, and S(CL) ) represents a mass ratio of the colored pigment in the colored pigment particles treated with surfactant to the colored pigment in the colored ink.
    [0002]
    2. Ink set used in inkjet recording apparatus, according to claim 1, characterized in that the black ink and the colored ink have a viscosity at 25°C of 5.0 mPa-s at 12 .0 mPa-s.
    [0003]
    3. Ink set used in inkjet recording apparatus, according to any one of claims 1 to 2, characterized in that the black ink and the colored ink comprise a fluorosurfactant and a silicone surfactant.
    [0004]
    4. Ink set used in inkjet recording apparatus, according to any one of claims 1 to 3, characterized in that the ink set satisfies Expression (4) and Expression (5) below:
    [0005]
    5. 0% by mass < P(Bk) < 10.0% by mass ... Expression (4)
    [0006]
    6. 0% by mass < P(CL) < 9.0% by mass ... Expression (5).
    [0007]
    7. Ink set used in inkjet recording apparatus, according to any one of claims 1 to 4, characterized in that the ink set satisfies Expression (3') below: 0.01 < [R (CL) / S(CL)] < [R(Bk) / S(Bk)] < 100 ... Expression (3').
    类似技术:
    公开号 | 公开日 | 专利标题
    BR102013009182B1|2021-06-29|INK SET USED IN INK JET RECORDING APPLIANCE
    JP6051805B2|2016-12-27|Ink jet recording ink, ink cartridge, ink jet recording method, ink jet recording apparatus, ink recorded matter
    JP6124070B2|2017-05-10|Ink for inkjet recording
    US8801167B2|2014-08-12|Inkjet recording apparatus, method for inkjet recording, and ink
    US8733920B2|2014-05-27|Inkjet recording ink, ink cartridge, inkjet recording device, inkjet recording method, and ink recorded matter
    ES2839221T3|2021-07-05|Inkjet ink, ink cartridge, inkjet recording method, inkjet recording device and inkjet engraved matter
    JP6252168B2|2017-12-27|Ink, ink cartridge, ink jet recording apparatus, ink jet recording method, and ink recorded matter
    JP2013155322A|2013-08-15|Ink
    EP2449042A1|2012-05-09|Aqueous ink for liquid jetting device and ink cartridge containing the same
    JP5652657B2|2015-01-14|Ink set and ink jet recording method
    JP5880844B2|2016-03-09|Ink jet recording ink, ink cartridge, ink jet recording method, ink jet recording apparatus, and ink recorded matter
    JP5659879B2|2015-01-28|Ink set, manufacturing method thereof, and ink jet recording apparatus
    JP6464920B2|2019-02-06|Ink, ink cartridge, and ink jet recording apparatus
    JP6256163B2|2018-01-10|Inkjet ink
    JP2015081273A|2015-04-27|Ink for inkjet recording
    JP2012096369A|2012-05-24|Inkjet recording apparatus
    JP2016130296A|2016-07-21|Ink for inkjet recording, ink cartridge, and inkjet recording device
    JP2017105908A|2017-06-15|Ink, ink cartridge, inkjet recording device
    JP7005899B2|2022-01-24|Liquid ejection device, image forming set, ink and image forming method
    JP2018111233A|2018-07-19|Liquid discharge device, image formation set, ink and image formation method
    JP2017002197A|2017-01-05|Ink, ink cartridge, inkjet recording device, inkjet recording method and ink recorded matter
    JP2015214670A|2015-12-03|Ink for inkjet recording, ink cartridge, and inkjet recording device
    同族专利:
    公开号 | 公开日
    JP2013221042A|2013-10-28|
    CN103374252A|2013-10-30|
    BR102013009182A2|2015-06-09|
    EP2650339A1|2013-10-16|
    EP2650339B1|2015-08-12|
    JP5942557B2|2016-06-29|
    CN103374252B|2015-01-28|
    US8956451B2|2015-02-17|
    US20130271524A1|2013-10-17|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    DE19521960B4|1994-06-17|2008-03-13|Ricoh Co., Ltd.|Recording method using an ink composition|
    US6786588B2|2001-03-23|2004-09-07|Ricoh Company Limited|Pretreatment liquid for recording material and image recording method using the pretreatment liquid|
    EP1167046B1|2000-06-21|2006-05-17|Canon Kabushiki Kaisha|Ink jet recording apparatus and printing method thereof|
    US6730155B2|2000-06-30|2004-05-04|Ricoh Company, Ltd.|Aqueous ink composition|
    US6899751B2|2000-09-29|2005-05-31|Ricoh Company, Ltd.|Ink for ink jet recording, ink jet recording method, ink cartridge and ink jet recording apparatus|
    US6730149B2|2001-01-22|2004-05-04|Ricoh Company Limited|Ink composition and inkjet recording method and apparatus using the ink composition|
    JP2002283564A|2001-03-22|2002-10-03|Ricoh Co Ltd|Ink jet recorder, ink, and recording method|
    JP2002327138A|2001-05-01|2002-11-15|Seiko Epson Corp|Ink set for ink jet recording and method for ink jet recording|
    EP1262529A1|2001-05-29|2002-12-04|Ricoh Company, Ltd.|Ink set for ink jet recording, method for ink jet recording|
    CN100386215C|2001-09-20|2008-05-07|株式会社理光|Ink jet recording method, recording device, ink/ recording medium set, recording matter|
    ES2254946T3|2002-02-05|2006-06-16|Ricoh Company, Ltd.|INK FOR PRINTING WITH INK JET, INK SET, INK CARTRIDGE, PRINTER AND PRINTING PROCEDURE.|
    CN100448671C|2002-06-24|2009-01-07|株式会社理光|Inkjet recording apparatus and inkjet recording method|
    KR100685769B1|2003-06-30|2007-02-26|가부시키가이샤 리코|Inkjet recording ink, recording process and recording apparatus|
    JP2005170035A|2003-11-17|2005-06-30|Ricoh Co Ltd|Maintenance and recovery unit and maintenance and recovery method using ink which rapidly increases viscosity exceeding 50) during moisture evaporation 30-45% and inkjet recording apparatus|
    JP2005298806A|2004-03-19|2005-10-27|Ricoh Co Ltd|Recording ink, ink cartridge, ink recorded material, inkjet recording apparatus and inkjet recording method|
    EP1791917B1|2004-09-13|2011-09-07|Ricoh Company, Ltd.|Recording ink, ink cartridge, ink record, inkjet recording apparatus, and inkjet recording method|
    DE602005018507D1|2004-09-17|2010-02-04|Ricoh Kk|RECORDING INK, INK CARTRIDGE, INK RECORDING, INK RADIATION RECORDING DEVICE, AND INK RADIATION RECORDING METHOD|
    CN101213263B|2005-05-16|2012-05-16|卡伯特公司|Blends of carbon blacks and products containing the same|
    JP4803356B2|2005-08-15|2011-10-26|セイコーエプソン株式会社|Ink set, recording method using the same, and recorded matter|
    US8044114B2|2005-08-23|2011-10-25|Ricoh Company, Ltd.|Ink for recording, and ink cartridge, ink recorded matter, inkjet recording apparatus and inkjet recording method using the same|
    WO2007049782A1|2005-10-24|2007-05-03|Ricoh Company, Ltd.|Recording ink, recording ink set, records, ink cartridge, recording method, and inkjet recording apparatus|
    JP4928110B2|2005-10-26|2012-05-09|株式会社リコー|Ink set, ink cartridge, ink jet recording apparatus, and ink jet recording method|
    KR101045624B1|2006-09-15|2011-07-01|가부시키가이샤 리코|Inkjet recording ink, inkjet recording ink set, inkjet recording ink media set, ink cartridge, inkjet recording method and inkjet recording apparatus|
    WO2008032864A1|2006-09-15|2008-03-20|Ricoh Company, Ltd.|Recording ink, inkjet recording method and inkjet recording apparatus|
    CN101379150B|2006-09-19|2012-05-23|株式会社理光|Recording ink, ink media set, ink cartridge, ink recorded matter, inkjet recording apparatus, and inkjet recording method|
    CN101573419A|2006-12-28|2009-11-04|株式会社理光|Refill ink and ink cartridge|
    JP5360455B2|2007-11-26|2013-12-04|株式会社リコー|Inkjet recording ink, inkjet recording ink set, inkjet recording ink-media set, ink cartridge, inkjet recording method, inkjet recording apparatus|
    JP5403310B2|2007-12-26|2014-01-29|株式会社リコー|Ink jet recording ink, ink set for ink jet recording, ink media set for ink jet recording, ink cartridge, ink jet recording method, ink jet recording apparatus|
    JP5453750B2|2008-09-17|2014-03-26|株式会社リコー|Ink set for inkjet recording and inkjet recording method|
    JP5381015B2|2008-10-30|2014-01-08|株式会社リコー|Ink set for ink jet recording, ink cartridge, ink jet recording method, and ink jet recording apparatus|
    JP5568900B2|2008-10-30|2014-08-13|株式会社リコー|Ink jet recording ink, ink set, ink cartridge, recording method and recorded matter|
    JP5736668B2|2009-05-29|2015-06-17|株式会社リコー|Inkjet recording ink set, ink cartridge set, and inkjet recording apparatus|
    JP5776141B2|2009-06-23|2015-09-09|株式会社リコー|Ink jet recording ink, ink jet recording method using the ink, cartridge containing the ink, and recorded matter|
    JP5678464B2|2009-07-14|2015-03-04|株式会社リコー|Ink jet recording ink, ink cartridge, ink jet recording apparatus|
    JP5593969B2|2009-09-09|2014-09-24|株式会社リコー|Ink-jet recording ink and ink cartridge|
    JP5534160B2|2009-12-03|2014-06-25|株式会社リコー|Inkjet recording ink set, ink cartridge, recording apparatus using the same, image forming method, and image formed product|
    JP5672065B2|2010-03-02|2015-02-18|株式会社リコー|Ink jet recording ink, ink set for ink jet recording, ink cartridge, ink jet recording method, ink jet recording apparatus, and ink recorded matter|
    JP5725396B2|2010-04-30|2015-05-27|株式会社リコー|Inkjet recording ink, recording apparatus using the same, and recorded matter|
    JP2012000893A|2010-06-17|2012-01-05|Ricoh Co Ltd|Inkjet recording treatment liquid, inkjet cartridge, inkjet recording ink set, and inkjet recording method|
    US20110318551A1|2010-06-25|2011-12-29|Tomohiro Nakagawa|Inkjet recording ink, process for producing the inkjet recording ink, inkjet cartridge, inkjet recording apparatus, and inkjet recorded image|
    US8733920B2|2011-01-26|2014-05-27|Ricoh Company, Ltd.|Inkjet recording ink, ink cartridge, inkjet recording device, inkjet recording method, and ink recorded matter|
    JP5757405B2|2011-04-01|2015-07-29|株式会社リコー|Inkjet recording ink set, ink cartridge using the same, inkjet recording apparatus, image forming method, and image formed article|
    JP5729142B2|2011-06-02|2015-06-03|株式会社リコー|Ink jet recording ink, ink cartridge, ink jet recording apparatus, ink jet recording method, and ink recorded matter|
    JP2013067162A|2011-09-08|2013-04-18|Ricoh Co Ltd|Inkjet recording apparatus, method for forming inkjet image, and inkjet ink|JP6232798B2|2013-01-29|2017-11-22|株式会社リコー|Ink jet recording ink and recording method thereof|
    JP6291841B2|2013-01-30|2018-03-14|株式会社リコー|Inkjet water-based ink, inkjet recording method, inkjet recording|
    JP2014198466A|2013-03-13|2014-10-23|株式会社リコー|Image formation method using inkjet aqueous ink set coated by inkjet method and inkjet recording device|
    JP6295790B2|2013-06-24|2018-03-20|株式会社リコー|Water-based ink for ink jet, ink jet recording apparatus, ink jet recorded matter, and recording method|
    JP6149630B2|2013-09-13|2017-06-21|株式会社リコー|Water-based ink for ink jet, ink cartridge, ink jet recording apparatus|
    JP6149632B2|2013-09-17|2017-06-21|株式会社リコー|Water-based ink for ink jet, ink cartridge, ink jet recording apparatus|
    JP6171842B2|2013-10-24|2017-08-02|株式会社リコー|Inkjet water-based ink, inkjet recording apparatus, and inkjet recording method|
    JP2016006150A|2013-11-19|2016-01-14|株式会社リコー|Inkjet ink, ink cartridge, and inkjet recording device|
    US20170139339A1|2014-04-30|2017-05-18|Hewlett-Packard Indigo, B.V.|Electrostatic ink compositions|
    JP6302362B2|2014-06-13|2018-03-28|花王株式会社|Flexographic ink|
    JP6308065B2|2014-07-29|2018-04-11|株式会社リコー|Inkjet ink set and inkjet recording method|
    CN104277585B|2014-10-24|2017-01-11|成都普瑞斯特新材料有限公司|Environment-friendly colorful printing ink for handkerchief paper packages and preparation method thereof|
    JP6638232B2|2015-07-22|2020-01-29|株式会社リコー|Ink, ink cartridge, inkjet recording device, inkjet recording method, and recorded matter|
    JP2019130878A|2018-01-31|2019-08-08|セイコーエプソン株式会社|Liquid discharge device|
    JP2021070290A|2019-11-01|2021-05-06|セイコーエプソン株式会社|Inkjet recording device|
    法律状态:
    2015-06-09| B03A| Publication of a patent application or of a certificate of addition of invention [chapter 3.1 patent gazette]|
    2018-12-04| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|
    2020-02-18| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|
    2021-01-19| B06A| Notification to applicant to reply to the report for non-patentability or inadequacy of the application [chapter 6.1 patent gazette]|
    2021-04-27| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|
    2021-06-29| B16A| Patent or certificate of addition of invention granted|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 15/04/2013, OBSERVADAS AS CONDICOES LEGAIS. |
    优先权:
    申请号 | 申请日 | 专利标题
    JP2012-091660|2012-04-13|
    JP2012091660A|JP5942557B2|2012-04-13|2012-04-13|Ink set and ink jet recording method|
    [返回顶部]