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US6521034B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Ink, ink set, ink cartridge, recording unit, color-image recording apparatus, image recording process, color-image forming process, and method for improving density of ink-jet recorded image

Assignee: Canon Inc
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Filing: 2000-09-14
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Granted: 2003-02-18
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Expires: 2020-09-14
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Abstract

Abstract An ink is provided which suppresses the influence of the kinds of recording media on the image quality, is excellent in image quality, effectively inhibits the occurrence of bleed upon the formation of color images, is excellent in long-term shelf stability and stably forms high quality images. The ink contains at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.

Inventors

  • 👤 Koichi Osumi
  • 👤 Shinya Mishina
  • 👤 Tomonari Watanabe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 10:45
CPC Classifications
C; C09; C09D; C09D11/00; C09D11/30; C09D11/32; C09D11/324; B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/135; B41J2/14; B41J2/14016; B41J2/1433; C09D11/40; B41J2002/14169; B41J2002/14387; B41J2002/14475

Claims Analysis

Total Claims: 43
Claim 1
Independent Claim 90 words
An ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 2 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.
Claim 2
Dependent Claim 90 words
An ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 2 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.
Claim 3
Dependent Claim 29 words
The ink according to claim 1 , wherein the salt is contained in a proportion of 0.05 to 10% by weight based on the total weight of the ink.
Claim 4
Dependent Claim 29 words
The ink according to claim 2 , wherein the salt is contained in a proportion of 0.1 to 5% by weight based on the total weight of the ink.
Claim 5
Dependent Claim 30 words
The ink according to claim 1 , wherein the self-dispersing anionic carbon black has at least one hydrophilic group bonded directly or through another atomic group to the surface thereof.
Claim 6
Dependent Claim 55 words
The ink according to claim 4 , wherein the hydrophilic group is selected from the group consisting of —COO(M 2 ), —SO 2 (M 2 ) 2 , —PO 3 H(M 2 ) and —PO 3 (M 2 ) 2 , wherein M 2 is a hydrogen atom, an alkali metal, ammonium or organic ammonium.
Claim 7
Dependent Claim 35 words
The ink according to claim 4 , wherein said another atomic group is an alkylene group having 1 to 12 carbon atoms, a substituted or unsubstituted phenylene group, or a substituted or unsubstituted naphthylene group.
Claim 8
Dependent Claim 57 words
The ink according to claim 4 , wherein the hydrophilic group is selected from the group consisting of —COO(M 2 ), —SO 3 (M 2 ) 2 and —PO 3 (M 2 ) 2 , and M 2 in the above formulae is identical with M 1 in the formulae representing the salt in claim 1 .
Claim 9
Dependent Claim 113 words
An ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month in an environment of 60° C.
Claim 10
Dependent Claim 113 words
An ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month in an environment of 60° C.
Claim 11
Dependent Claim 25 words
The ink according to claim 1 or 8 , wherein the self-dispersing anionic carbon black has an average particle diameter of at least 90 nm.
Claim 12
Dependent Claim 17 words
The ink according to claim 1 or 8 , wherein the ink is an ink for ink-jet.
Claim 13
Dependent Claim 40 words
An ink set comprising in combination the black ink according to claim 1 or 8 , and a water-based color ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue.
Claim 14
Dependent Claim 24 words
The ink set according to claim 11 , wherein the coloring material for the color ink Is an acid dye or a direct dye.
Claim 15
Dependent Claim 19 words
The ink set according to claim 11 , wherein the coloring material for the color ink is a pigment.
Claim 16
Dependent Claim 13 words
The ink set according to claim 11 , which is used for ink-jet.
Claim 17
Dependent Claim 18 words
An ink cartridge, comprising an ink tank which contains the ink according to claim 1 or 8 .
Claim 18
Dependent Claim 113 words
A recording unit comprising an ink container portion containing an ink-jet ink and a head portion for ejecting the ink, the ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.08 (μmol/m 2 ) on its surface.
Claim 19
Dependent Claim 113 words
A recording unit comprising an ink container portion containing an ink-jet ink and a head portion for ejecting the ink, the ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.08 (μmol/m 2 ) on its surface.
Claim 20
Dependent Claim 133 words
A recording unit comprising an ink container portion containing an ink-jet ink and a head portion for ejecting the ink, the ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change In viscosity even when it is stored for one month in an environment of 60° C.
Claim 21
Dependent Claim 133 words
A recording unit comprising an ink container portion containing an ink-jet ink and a head portion for ejecting the ink, the ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change In viscosity even when it is stored for one month in an environment of 60° C.
Claim 22
Dependent Claim 112 words
An image recording apparatus comprising an ink container portion containing an ink-jet ink and a recording head for ejecting the ink, the ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) CO 31 wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.
Claim 23
Dependent Claim 112 words
An image recording apparatus comprising an ink container portion containing an ink-jet ink and a recording head for ejecting the ink, the ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) CO 31 wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.
Claim 24
Dependent Claim 131 words
An image recording apparatus comprising an ink container portion containing an ink-jet ink and a recording head for ejecting the ink, the ink comprising at least one-salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (ML)NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month in an environment of 60° C.
Claim 25
Dependent Claim 131 words
An image recording apparatus comprising an ink container portion containing an ink-jet ink and a recording head for ejecting the ink, the ink comprising at least one-salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (ML)NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month in an environment of 60° C.
Claim 26
Dependent Claim 148 words
A color-image recording apparatus comprising an ink container portion containing an ink-jet ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface, another ink container portion containing a water-based color ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue, and recording head portions for respectively ejecting the inks contained in the respective ink container portions.
Claim 27
Dependent Claim 148 words
A color-image recording apparatus comprising an ink container portion containing an ink-jet ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface, another ink container portion containing a water-based color ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue, and recording head portions for respectively ejecting the inks contained in the respective ink container portions.
Claim 28
Dependent Claim 169 words
A color-image recording apparatus comprising an ink container portion containing an ink-jet ink comprising at least one salt selected from the group consisting of (M 1 I) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 1 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month In an environment of 60° C., another ink container portion containing a water-based, ink-jet color ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue, and recording head portions for respectively ejecting the inks contained in the respective Ink container portions.
Claim 29
Dependent Claim 169 words
A color-image recording apparatus comprising an ink container portion containing an ink-jet ink comprising at least one salt selected from the group consisting of (M 1 I) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 1 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month In an environment of 60° C., another ink container portion containing a water-based, ink-jet color ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue, and recording head portions for respectively ejecting the inks contained in the respective Ink container portions.
Claim 30
Dependent Claim 125 words
An image recording process comprising the step of ejecting an ink-jet ink toward the surface of a recording medium to apply the ink to the surface thereof, thereby recording an image, wherein the ink comprises at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.
Claim 31
Dependent Claim 125 words
An image recording process comprising the step of ejecting an ink-jet ink toward the surface of a recording medium to apply the ink to the surface thereof, thereby recording an image, wherein the ink comprises at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface.
Claim 32
Dependent Claim 143 words
An image recording process comprising the step of ejecting an ink toward the surface of a recording medium to apply the ink to the surface thereof, thereby recording an image, wherein the ink comprises at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month in an environment of 60° C.
Claim 33
Dependent Claim 143 words
An image recording process comprising the step of ejecting an ink toward the surface of a recording medium to apply the ink to the surface thereof, thereby recording an image, wherein the ink comprises at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the ink undergoing no substantial change in viscosity even when it is stored for one month in an environment of 60° C.
Claim 34
Dependent Claim 21 words
The image recording process according to claim 22 or 23 , wherein the energy for ejecting the ink is thermal energy.
Claim 35
Dependent Claim 21 words
The image recording process according to claim 22 or 23 , wherein the energy for ejecting the ink is mechanical energy.
Claim 36
Dependent Claim 164 words
A process for forming a color image comprising the steps of ejecting a first water-based, ink-jet ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue toward the surface of a recording medium to apply the ink to the surface thereof; and ejecting a second ink-jet ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface toward the surface of the recording medium to apply the second ink to the surface thereof.
Claim 37
Dependent Claim 164 words
A process for forming a color image comprising the steps of ejecting a first water-based, ink-jet ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue toward the surface of a recording medium to apply the ink to the surface thereof; and ejecting a second ink-jet ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 1.8 (μmol/m 2 ) on its surface toward the surface of the recording medium to apply the second ink to the surface thereof.
Claim 38
Dependent Claim 188 words
A process for forming a color image comprising the steps of ejecting a first water-based, ink-jet ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue toward the surface of a recording medium to apply the ink to the surface thereof; and ejecting a second ink-jet ink toward the surface of the recording medium to apply the second ink to the surface second ink-jet ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the second ink-jet ink undergoing no substantial change in viscosity even when it is stored for one month In an environment of 60° C.
Claim 39
Dependent Claim 188 words
A process for forming a color image comprising the steps of ejecting a first water-based, ink-jet ink comprising at least one coloring material selected from among coloring materials for cyan, magenta, yellow, red, green and blue toward the surface of a recording medium to apply the ink to the surface thereof; and ejecting a second ink-jet ink toward the surface of the recording medium to apply the second ink to the surface second ink-jet ink comprising at least one salt selected from the group consisting of (M 1 ) 2 SO 4 , CH 3 COO(M 1 ), Ph-COO(M 1 ), (M 1 )NO 3 , (M 1 )Cl, (M 1 )Br, (M 1 )I, (M 1 ) 2 SO 3 and (M 1 ) 2 CO 3 , wherein M 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group, and a self-dispersing anionic carbon black having a functional-group density of at least 0.45 (mmol/g) on its surface, the second ink-jet ink undergoing no substantial change in viscosity even when it is stored for one month In an environment of 60° C.
Claim 40
Dependent Claim 77 words
A water-based ink-jet ink comprising a self-dispersing carbon black having an average particle diameter of at least 90 nm and being stably dispersed in an aqueous medium, and a salt, wherein the carbon black has a surface functional-group density of at least 1.8 μmol/m 2 and gives an optical density of an image obtained by the ink, the optical density being decreased if the salt is not present, and the salt alleviates the decrease in optical density.
Claim 41
Dependent Claim 77 words
A water-based ink-jet ink comprising a self-dispersing carbon black having an average particle diameter of at least 90 nm and being stably dispersed in an aqueous medium, and a salt, wherein the carbon black has a surface functional-group density of at least 1.8 μmol/m 2 and gives an optical density of an image obtained by the ink, the optical density being decreased if the salt is not present, and the salt alleviates the decrease in optical density.
Claim 42
Independent Claim 100 words
A method for improving the optical density of an ink-jet recorded image formed with an ink comprising a self-dispersing carbon black having an average particle diameter of at least 90 nm and a surface functional-group density of at least 1.8 μmol/m 2 and being stably dispersed in an aqueous medium, the method comprising causing a salt to be contained in the ink as an agent for inhibiting penetration of the self-dispersing carbon black into the interior of a recording medium, the optical density being decreased if the salt is not present, and the salt alleviates the decrease in optical density.
Claim 43
Independent Claim 100 words
A method for improving the optical density of an ink-jet recorded image formed with an ink comprising a self-dispersing carbon black having an average particle diameter of at least 90 nm and a surface functional-group density of at least 1.8 μmol/m 2 and being stably dispersed in an aqueous medium, the method comprising causing a salt to be contained in the ink as an agent for inhibiting penetration of the self-dispersing carbon black into the interior of a recording medium, the optical density being decreased if the salt is not present, and the salt alleviates the decrease in optical density.

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