Abstract: The present invention relates to a method for treating liquids used in inkjet recording comprising, providing a first printing liquid and a second printing liquid that is capable of reacting with the first printing liquid to cause coagulation and thickening if mixed with the first printing liquid, and exposing the first and second printing liquids to each other to form a mixture, wherein when the mixture includes a coagulation-thickening preventing agent which prevents the reaction of the printing liquids.

Abstract: The present invention relates to a method for treating liquids used in inkjet recording comprising, providing a first printing liquid and a second printing liquid that is capable of reacting with the first printing liquid to cause coagulation and thickening if mixed with the first printing liquid, and exposing the first and second printing liquids to each other to form a mixture, wherein when the mixture includes a coagulation-thickening preventing agent which prevents the reaction of the printing liquids.

Abstract: The present invention relates to a method for treating liquids used in inkjet recording including, providing a first printing liquid and a second printing liquid that is capable of reacting with the first printing liquid to cause coagulation and thickening if mixed with the first printing liquid, and exposing the first and second printing liquids to each other to form a mixture, wherein when the mixture includes a coagulation-thickening preventing agent which prevents the reaction of the printing liquids.

Abstract: An ink jet recording ink is provided containing water, a pigment that is self-dispersible in water, a water-soluble organic solvent, and a nonionic polymer of which the amount is preferably in a range of about 5% by mass to about 200% by mass relative to the total mass of the pigments. The nonionic polymer is preferably selected from a group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, poly N-vinyl acetamide, and the like. The absolute value of zeta potential of the ink is preferably in the range of about 5 mV to about 30 mV.

Abstract: The present invention provides an ink set for ink jet recording comprising: an ink which contains: water; a colorant; a water-soluble organic solvent; polyvalent metal ions; and compound (A) which is intrinsically capable of substantially inactivating the polyvalent metal ions, and a liquid composition is of a pH in which the polyvalent metal ions in the ink can be substantially activated. The pH of the ink is within a range in which compound (A) keeps the polyvalent metal ions substantially in an inactive state. The invention also provides an ink jet recording method which uses such an ink set.

Abstract: A double-sided printable image recording apparatus comprising: a conveying means for conveying a recording medium, a fixed recording head for ejecting an aqueous ink and a treating liquid having nature of aggregating a colorant contained in the aqueous ink to a recording medium conveyed by the conveying means, which is arranged in a direction substantially orthogonal to a conveying direction of the recording medium, and has a printing region of a recording medium width, and an ejection controlling means for controlling ejection of the aqueous ink and the treating liquid from the fixed recording head based on image information, wherein the ejection controlling means, in a double-sided printed mode of printing on both sides of the recording medium, controls an ejection amount of a treating liquid ejected per recording medium to a smaller amount than that of a single-sided printing mode of printing only on one side, at least on a surface of a recording medium.

Abstract: The present invention provides a liquid absorbing member for absorbing excessive ink components from an ink image formed on a recording medium by an ink jet recording method, in which the liquid absorbing member contains fibrous matter, and the fiber thickness of fibers composing the fibrous matter is in a range of about 0.01 to 100 dtex. The fibrous matter preferably contains fibers having a fiber diameter in a range of about 0.5 to 10 ?m, and fibers composing the fibrous matter are preferably polyester fibers. The invention also provides an ink jet recording apparatus comprising a printhead and the liquid absorbing member.

Abstract: The present invention provides an ink-jet recording method adopting an ink-jet recording apparatus including a printer head, which accommodates one or more kinds of ink and has a nozzle face on which one or more nozzles are provided, wherein the printer head is tilted when printing is being stopped so that an axis intersecting with the nozzle face at a right angle is displaced by 3 or more degrees from a direction of the axis when printing is being conducted, and an ink-jet recording apparatus used in the method.

Abstract: The present invention relates to a method for treating liquids used in inkjet recording comprising, providing a first printing liquid and a second printing liquid that is capable of reacting with the first printing liquid to cause coagulation and thickening if mixed with the first printing liquid, and exposing the first and second printing liquids to each other to form a mixture, wherein when the mixture includes a coagulation-thickening preventing agent which prevents the reaction of the printing liquids.

Abstract: An ink jet recording ink is provided containing water, a pigment that is self-dispersible in water, a water-soluble organic solvent, and a nonionic polymer of which the amount is preferably in a range of about 5% by mass to about 200% by mass relative to the total mass of the pigments. The nonionic polymer is preferably selected from a group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, poly N-vinyl acetamide, and the like. The absolute value of zeta potential of the ink is preferably in the range of about 5 mV to about 30 mV.

Abstract: The present invention provides an ink set for ink jet recording comprising: an ink which contains: water; a colorant; a water-soluble organic solvent; polyvalent metal ions; and compound (A) which is intrinsically capable of substantially inactivating the polyvalent metal ions, and a liquid composition is of a pH in which the polyvalent metal ions in the ink can be substantially activated. The pH of the ink is within a range in which compound (A) keeps the polyvalent metal ions substantially in an inactive state. The invention also provides an ink jet recording method which uses such an ink set.

Abstract: The present invention provides an ink-jet recording method adopting an ink-jet recording apparatus including a printer head, which accommodates one or more kinds of ink and has a nozzle face on which one or more nozzles are provided, wherein the printer head is tilted when printing is being stopped so that an axis intersecting with the nozzle face at a right angle is displaced by 3 or more degrees from a direction of the axis when printing is being conducted, and an ink-jet recording apparatus used in the method.

Abstract: The ink-jet recording method and apparatus use an ink containing at least, a pigment self-dispersible in water, a water soluble organic solvent and water, and carry out printing with an amount of the ink of 20 ng or less per one droplet, and the ink satisfies the following conditions: a dynamic contact angle upon dropping 4 &mgr;L of the ink on plain paper is about 60° or less after one second from dropping; a volume average particle diameter mv of dispersed particles of the pigment in the ink is about from 150 to 250 nm; and in the dispersed particles, a number of particles having a particle diameter of from 0.5 to 5 &mgr;m is about from 25×104 to 2,000×104 per microliter, and a number of particles having a particle diameter of 5 &mgr;m or more is about 100 per microliter or less.

Abstract: The ink-jet recording method and apparatus use an ink containing at least, a pigment self-dispersible in water, a water soluble organic solvent and water, and carry out printing with an amount of the ink of 20 ng or less per one droplet, and the ink satisfies the following conditions: a dynamic contact angle upon dropping 4 &mgr;L of the ink on plain paper is about 60° or less after one second from dropping; a volume average particle diameter mv of dispersed particles of the pigment in the ink is about from 150 to 250 nm; and in the dispersed particles, a number of particles having a particle diameter of from 0.5 to 5 &mgr;m is about from 50×104 to 2,000×104 per microlitter, and a number of particles having a particle diameter of 5 &mgr;m or more is about 100 per microlitter of less.

Abstract: In an aqueous ink jet recording liquid including at least water, a water-soluble organic solvent and a water-insoluble coloring material, (1) the absolute value of the zeta potential is 20 mV or more, (2) the conductivity is from 0.05 to 0.75 S/m, (3) the number average particle size of dispersed particles is from 15 to 200 nm, and (4) the number of particles having a particle size of 0.5 &mgr;m or more present in one liter is 2.5×1011 or less. Due to the aforementioned, dispersion stability of the coloring material can be maintained in the ink jet recording liquid in which the water-insoluble coloring material is dispersed, and the aqueous ink jet recording liquid is provided, which is excellent regarding stability over long periods of time, causes no ink flow route clogging and prevents kogation in printing, provides a recorded material having excellent rub resistance, printing quality, optical density, water resistance and lightfastness, and can prevent uneven density.

Abstract: An ink for ink jet printing which contains as essential components pigment, water-soluble organic solvent, and water. The ink contains particles, after ink jetting, such that the number-average particle diameter is 10 to 150 nm and the number of particles larger than 0.5 &mgr;m is 6×104 to 6×105/&mgr;l and the number of particles larger than 5 &mgr;m is less than 50/&mgr;l. This ink may be used in combination with a second liquid which contains a water-soluble organic solvent having a solubility parameter of 9 to 11, and/or surfactant, and water. A method of ink jet printing uses the ink or a combination of the ink and the liquid. The ink possesses the characteristics of both optical density and storage stability. The liquid prevents the mixing of colors of adjacent printed images.

Abstract: Disclosed is an ink for ink jet recording comprising water, a water-soluble organic solvent, a pigment and a dispersant, wherein the dispersant has a hydrophilic moiety and a hydrophobic moiety and comprises a copolymer obtained by copolymerizing from 40 to 80 mol % of a monomer having an &agr;,&bgr;-ethylenically unsaturated group constituting the hydrophilic moiety and from 20 to 60 mol % of a monomer having an &agr;,&bgr;-ethylenically unsaturated group constituting the hydrophobic moiety.

Abstract: Disclosed is an ink jet recording ink comprising water, an aqueous organic solvent, a surfactant and a self-dispersible pigment, wherein the number average particle diameter of dispersed particles of the pigment is from 15 to 100 nm, given that mv is the volumetric average particle diameter of the dispersed particles of said pigment and mn is the number average diameter of the dispersed particles of said pigment, mv/mn is less than or equal to 3, the number of particles having a particle diameter greater than or equal to 0.5 .mu.m among the dispersed particles of the pigment contained in one liter of the ink is less than or equal to 7.5.times.10.sup.10, the surface tension of the ink is less than or equal to 60 mN/m, the electroconductivity of the ink is from 0.05 to 0.4 S/m and the pH of the ink is from 6 to 11. This ink provides a high storage stability and a uniform image having high water-resistance, resolution, and density can be obtained.

Abstract: An ink recording method is disclosed, which comprises printing a recording paper with an aqueous ink and immediately thereafter applying pressure onto the recording paper, whereby sharp images can be printed at high speed even on a plain paper.

Abstract: Disclosed is an ink holding material to be put in an ink tank of an ink jet recording device, which is such that when it is extracted with pure water, the electrical conductivities and the surface tensions of the water before and after the extraction satisfy relationship (1):350 .gtoreq..gamma.r/.sigma.r-.gamma.s/.sigma.s.gtoreq.0 (1)wherein .gamma.r represents the surface tension (mN/m) of pure water before extraction; .sigma.r represents the electrical conductivity (mS/m) of pure water before extraction; .gamma.s represents the surface tension (mN/m) of pure water after extraction; and .sigma.s represents the electrical conductivity (mS/m) of pure water after extraction.