JP2001162920A - Liquid composition, ink set, recording method, ink cartridge, recording unit, method for forming multi-color image, ink-jet device, method for accelerating fixing of ink to recording medium, and method for improving quality of multi-color image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid composition which can alleviate the effect of a recording medium on image quality and produce a quality image stably. SOLUTION: The liquid composition used for forming an ink-jet image together with an ink containing a coloring material which is dispersed in an aqueous medium by the action of an ionic group contains at least one salt selected from (M1)2SO4, CH3COO(M1), Ph-COO(M1), (M1)NO3, (M1)Cl, (M1)Br, (M1)I, (M1)2SO4, and (M1)2CO3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid composition, an ink set, an ink cartridge, a recording unit, a recording method, an ink jet apparatus, a method for accelerating fixing of ink to a recording medium, and a method for improving the quality of a multicolor image. is there.

[0002]

2. Description of the Related Art Writing instruments (fountain pens, felt-tip pens,
As black inks for aqueous ballpoint pens and the like, and black inks for inkjets, inks using carbon black, which is a black colorant having a high density of printed matter and excellent in fastness and the like, have been proposed.

[0003] In particular, in recent years, ink has been used so that good recording can be performed on plain paper such as copy paper, report paper, notebooks, stationery, bond paper, and continuous slip paper generally used in offices. Detailed research and development have been made from various aspects such as composition and physical properties. For example, JP-A-61-283875 and JP-A-64-6074 disclose aqueous pigment inks containing carbon black and a dispersant. JP-A-8-3498 cites a technical problem that when ink containing carbon black together with a dispersant is used as an ink for an ink jet printer, ejection becomes unstable or a sufficient print density cannot be obtained. As an ink that can solve such a problem, an aqueous pigment ink using self-dispersion type carbon black without using a dispersant is disclosed.

Further, dyes have been used as color materials in color inks. Dyes have advantages in terms of excellent color development and stability, but are required to be further improved in terms of water resistance, light resistance and the like. In recent years, in order to improve these problems, many aqueous inks using an organic pigment instead of a dye have been proposed. For example, JP 9-40
No. 898 discloses an idea of adsorbing a low-molecular compound having high hydrophilicity on the surface of an organic pigment to achieve both storage stability and printing quality. Also, organic pigment dispersions in which a functional group is directly bonded to the pigment surface are disclosed in US Pat. No. 5,837,045 and the like, similarly to carbon blacks which can be stably dispersed / dissolved in water without using a dispersant, which have been conventionally proposed. Have been. However, the present inventors have conducted various studies on the case where ink containing a color material such as carbon black and an organic pigment is used for ink jet recording. As a result, in order to improve the image density and the color developing property, In order to improve the image density and the color developing property by making the composition not to penetrate into the recording medium, a new problem for lowering the penetrating property is that a different color at the boundary between the colors because it remains on the recording medium without penetrating. Bleeding between each other (hereinafter, referred to as bleed) occurred.

In order to suppress the occurrence of bleeding between different colors at the boundary between colors, for example, Japanese Patent Application Laid-Open No. 06-228478 uses an ink set composed of a colorless liquid and ink. To increase the viscosity of the ink or to coagulate or precipitate the color material in the ink, thereby promoting the separation (solid-liquid) of the ink solid (color material, etc.) and liquid on the recording medium. Is disclosed.

[0006]

By using the above-described technique, the bleeding between inks of different colors at the boundary between colors can be suppressed extremely effectively. However, since the ionic reaction is used, the ink and the liquid composition immediately react when mixed. Therefore, for example, when such a combination is used as an ink set for inkjet, it is necessary to completely separate the recovery system of the inkjet head of the ink and the liquid composition. That is, when the recovery system of the ink and the liquid composition is shared, the ink and the liquid composition react in the recovery system, and the ink component is solidified. As a result, the function of the recovery system of the inkjet head may gradually decrease. On the other hand,
Providing a plurality of recovery systems in the ink jet apparatus may hinder miniaturization of the apparatus and may increase the product cost.

The present invention has been made in view of such a technical background, and an object of the present invention is to provide a liquid composition capable of realizing high quality images at low cost.

It is another object of the present invention to provide an ink set capable of forming a high-quality image.

It is another object of the present invention to provide a recording method capable of forming a high-quality image.

[0010] The present invention also provides a method for suppressing bleeding.
It is another object to provide a method for forming a high quality multicolor image.

Another object of the present invention is to provide a recording unit and an ink cartridge which can be used for forming a high-quality image.

Another object of the present invention is to provide an ink jet recording apparatus capable of forming a high quality image.

Another object of the present invention is to provide a method for promoting the fixing of ink to a recording medium for forming a high quality image.

Another object of the present invention is to provide a method for suppressing bleeding and improving the quality of a multicolor image.

[0015]

The liquid composition according to one embodiment of the present invention, which can achieve the above object, comprises:
A liquid composition used for forming an ink-jet image together with an ink containing a coloring material dispersed in an aqueous medium by the action of an ionic group, comprising (M1) ₂ S
O ₄ , CH ₃ COO (M1), Ph-COO (M1),
(M1) NO ₃ , (M1) Cl, (M1) Br, (M
1) It is characterized by containing at least one salt selected from I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ (where M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents phenyl Represents a group).

An ink set according to an embodiment of the present invention, which can achieve the above object, includes, for example, an ink containing a coloring material dispersed in an aqueous medium and in the aqueous medium by the action of an ionic group. And a combination of the above liquid composition.

Further, a recording method according to an embodiment of the present invention that can achieve the above object includes (i) an aqueous medium and a coloring material dispersed in the aqueous medium by the action of an ionic group. Applying ink to a recording medium;
And (ii) (M1) ₂ SO ₄ , CH ₃ COO (M1),
Ph-COO (M1), (M1) NO ₃ , (M1) C
1, a liquid composition containing at least one salt selected from (M1) Br, (M1) I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ (where M1 is an alkali metal, ammonium or organic ammonium) And Ph represents a phenyl group) in at least an area of the recording medium to which the ink is applied.

According to another aspect of the present invention, there is provided a method for forming a multi-color image which includes images of different tones on a recording medium, wherein the images having different tones have portions adjacent to each other. A method of forming a multicolor image having a step of applying a plurality of inks having different color to each other to a recording medium to form the image, wherein at least one of the plurality of inks is an aqueous medium and A colorant-dispersed ink containing a colorant dispersed in the aqueous medium by the action of an ionic group, and further comprising, for example, (M
1) ₂ SO ₄ , CH ₃ COO (M1), Ph-COO (M
1), (M1) NO ₃ , (M1) Cl, (M1) Br,
(M1) A liquid composition containing at least one salt selected from I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ is added to the colorant-dispersed ink prior to application to a recording medium, or A step of applying the material-dispersed ink after applying the ink to the recording medium.

The recording unit according to an embodiment of the present invention which can achieve the above object is, for example, (M
1) ₂ SO ₄ , CH ₃ COO (M1), Ph-COO (M
1), (M1) NO ₃ , (M1) Cl, (M1) Br,
(M1) A liquid composition containing at least one salt selected from I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ (provided that
M1 represents an alkali metal, ammonium, or organic ammonium, and Ph represents a phenyl group), and a liquid composition containing section containing a liquid composition and an ink jet head for discharging the liquid composition. is there.

A book which can achieve the above object.
A recording unit according to another embodiment of the present invention includes, for example,
(M1)_TwoSO_Four, CH_ThreeCOO (M1), Ph-COO
(M1), (M1) NO_Three, (M1) Cl, (M1) B
r, (M1) I, (M1)_TwoSO _ThreeAnd (M1)_TwoCO_Three
A liquid composition containing at least one salt selected from
And M1 is an alkali metal, ammonium or organic anion.
Monium and Ph represents a phenyl group)
Liquid composition storage section, and an ink for discharging the liquid composition.
Jet head, aqueous medium and ionic group
Containing a color material dispersed by the action of
And an ink container for storing the ink.
It is characterized by having an ink jet head.

The ink cartridge according to an embodiment of the present invention which can achieve the above object is, for example, (M1) ₂ SO ₄ , CH ₃ COO (M1), Ph-CO
O (M1), (M1) NO ₃ , (M1) Cl, (M1)
Br, (M1) I, (M1) ₂ SO ₃ and (M1) ₂ C
An ink jet head that contains a liquid composition containing at least one salt selected from O ₃ (where M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group) and discharges the liquid composition It is characterized in that it can be attached to and detached from.

Further, the ink jet apparatus according to one embodiment of the present invention which can achieve the above object includes, for example, (M1) ₂ SO ₄ , CH ₃ COO (M1), Ph-CO
O (M1), (M1) NO ₃ , (M1) Cl, (M1)
Br, (M1) I, (M1) ₂ SO ₃ and (M1) ₂ C
A liquid composition containing a liquid composition containing at least one salt selected from O ₃ (where M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group); An ink container containing an ink containing a coloring material dispersed in an aqueous medium by the action of an ionic group, a liquid composition contained in the liquid composition container, and a liquid composition contained in the ink container. An ink jet head for independently discharging each of the inks is provided.

The ink jet apparatus according to another embodiment of the present invention, which can achieve the above object, includes (M1) ₂ SO ₄ , CH ₃ COO (M1), Ph-C
OO (M1), (M1) NO ₃ , (M1) Cl, (M
1) Br, (M1) I, (M1) ₂ SO ₃ and (M1)
Liquid composition containing at least one salt selected from ₂ CO ₃ (where M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group)
A first recording unit including a liquid composition storage section containing the liquid composition and an inkjet head for discharging the liquid composition;
And a second recording unit including an aqueous medium and an ink containing section containing an ink containing a coloring material dispersed in the aqueous medium by the action of an ionic group, and an inkjet head for discharging the ink. It is characterized by the following.

According to one embodiment of the present invention, which can achieve the above object, the method of accelerating fixing of an ink to a recording medium is performed by dispersing an aqueous medium and an ionic group in the aqueous medium. A method for promoting fixing of an ink containing a color material to a recording medium when the ink is applied to the recording medium using an inkjet apparatus, comprising: (M1) ₂ S
O ₄ , CH ₃ COO (M1), Ph-COO (M1),
(M1) NO ₃ , (M1) Cl, (M1) Br, (M
1) A liquid composition containing at least one salt selected from I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ (where M1
Represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group) at least in a portion of the recording medium to which the ink is applied.

A book which can achieve the above object.
A method for improving the quality of a multicolor image according to an embodiment of the present invention includes:
A method for improving the quality of a multicolor image on a recording medium, comprising:
The multicolor image has at least a first region having a different tone and a second region.
And the first region and the second region are at least
Are also partially adjacent to each other, and the first region
Applies a first ink having a first color tone to the recording medium
And at least the first input on the recording medium.
Including a step of applying a liquid composition to a site to which
The second region is formed by a method.
Applying a second ink having a color tone of 2 to the recording medium
Formed by a method having a step,
Ink 1 is an aqueous medium and the action of ionic groups on the aqueous medium
Ink containing a color material dispersed by
The liquid composition comprises (M1)_TwoSO_Four, CH_ThreeCOO (M
1), Ph-COO (M1), (M1) NO_Three, (M
1) Cl, (M1) Br, (M1) I, (M1)_TwoSO _Three
And (M1)_TwoCO_ThreeAt least one salt selected from
(Where M1 is an alkali metal,
Ammonium or organic ammonium;
Represents a phenyl group).

According to the above-described various embodiments of the present invention, for example, image quality can be improved. Specifically, for example, it is possible to form a high-quality image even when printed on a highly permeable paper that may impair the sharpness of characters or cause a decrease in image density and color development, Further, the fixability to paper can be improved.

According to the various embodiments of the present invention, in addition to the above-described effects, bleeding in a multicolor image can be extremely effectively prevented, and a high-quality multicolor image can be obtained.

Although it is not clear why such various effects can be obtained by such an embodiment, it is presumed as follows.

That is, when the liquid composition is applied to the recording medium, the solvent in the liquid composition penetrates into the recording medium or evaporates into air, and the salt concentration of the liquid composition on the surface of the recording medium decreases. It rises sharply. When a liquid composition causing such a phenomenon and a coloring material such as a pigment are applied so that the ink is stably dispersed by the action of an ionic group, for example, an anionic group, so as to come into contact with the recording medium surface, the recording is performed. When the salt concentration of the liquid composition on the medium increases, the dispersion stability of the coloring material in the ink is lost, and the coloring material aggregates and precipitates. That is, the separation between the coloring material constituting the ink and the aqueous medium is promoted. As a result, penetration of the coloring material into the recording medium is suppressed, and an image having excellent contour sharpness and the like can be formed. In addition, since the solid-liquid separation of the ink occurs quickly, it is considered that the above-described phenomenon is unlikely to occur even on paper having relatively high permeability. In other words, it is considered that factors such as the size of the permeability and the like are less likely to be affected. Further, since the liquid composition and the ink according to the present invention do not immediately react by mixing as described above, even when used as an ink set for an inkjet, for example, the recovery system of the inkjet head should be shared. There is also an advantage that you can do.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Liquid Composition) A liquid composition capable of destroying the dispersion stability of a coloring material dispersed in an aqueous medium by the action of an ionic group on the recording medium. Preferably contains a salt and an aqueous medium.

(Salt) Here, examples of the salt include (M1) ₂ SO ₄ , CH ₃ COO (M1), Ph-C
OO (M1), (M1) NO ₃ , (M1) Cl, (M
1) Br, (M1) I, (M1) ₂ SO ₃ and (M1)
_It is preferable to use at least one selected from ₂ CO ₃ . Here, M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group. As specific examples of the alkali metal, for example, Li, Na,
K, Rb, Cs and the like. Specific examples of the organic ammonium include, for example, methyl ammonium, dimethyl ammonium, trimethyl ammonium, ethyl ammonium, diethyl ammonium, triethyl ammonium, methanol ammonium, dimethanol ammonium, trimethanol ammonium, and ethanol ammonium. , Diethanolammonium and triethanolammonium. The content of the salt in the liquid composition is 1 to 20 in consideration of the effects of the present invention.
wt% is preferred. Further, the liquid composition does not necessarily have to show absorption in the visible region.

(Aqueous Medium) Examples of the aqueous medium used in the liquid composition according to the present embodiment include water or a mixed solvent of water and a water-soluble organic solvent. As the water-soluble organic solvent, those having an effect of preventing drying of the liquid composition are particularly preferable. Specifically, for example, carbon number of 1-4 such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol
Amides such as dimethylformamide and dimethylacetamide; ketones or keto alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol Alkylene glycols having an alkylene group containing 2 to 6 carbon atoms, such as propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol; polyethylene Lower alkyl ether acetates such as glycol monomethyl ether acetate; glycerin; ethylene glycol monomethyl (or ethyl)
Ether, diethylene glycol methyl (or ethyl)
Lower alkyl ethers of polyhydric alcohols such as ether and triethylene glycol monomethyl (or ethyl) ether; polyhydric alcohols such as trimethylolpropane and trimethylolethane; N-methyl-2-pyrrolidone;
-Pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. The water-soluble organic solvents as described above can be used alone or as a mixture.

It is desirable to use deionized water as the water.

The content of the water-soluble organic solvent contained in the liquid composition according to this embodiment is not particularly limited, but is preferably in the range of 3 to 50% by weight based on the total weight of the liquid composition. . Further, the content of water contained in the liquid composition is preferably 50 to 95% by weight based on the total weight of the liquid composition.
Range.

In addition to the above components, if necessary, a surfactant may be used to obtain a liquid composition having desired physical properties.
An antifoaming agent, a preservative, a fungicide and the like can be added, and a coloring material such as a commercially available water-soluble dye may be added.

(Ink) The above-described liquid composition can obtain favorable effects such as formation of a high quality image by being used for recording in combination with an ink in which a coloring material is dispersed in an aqueous medium by an ionic group. .

Examples of the coloring material that can be used in such an ink include pigments, microencapsulated pigments, and colored resins. Hereinafter, these coloring materials will be described in detail.

(Pigment) Examples of pigments that can be used include carbon black and organic pigments.

(Carbon Black) Examples of carbon black include furnace black, lamp black,
Carbon black pigments such as acetylene black and channel black, for example, Raven 7
000, Ray-Van 5750, Ray-Van 5250, Ray-Van 5000, Ray-Van 3500, Ray-Van 2
000, Ray-Van 1500, Ray-Van 1250, Ray-Van 1200, Ray-Van 1190ULTRA-I
I, Ray-Van 1170, Ray-Van 1255 (all manufactured by Columbia), Black Pearls (Black Pe
arls) L, Regal 400R, Legal 330R, Legal 660R, Mogul (Mogu)
l) L, Monarch 700, Monak 80
0, Monac 880, Monac 900, Monac 1000, Monac 1100, Monac 1300, Monac 1400, Valcan XC-72R (all manufactured by Cabot Corporation), Color Black (Color Black) F
W1, color black FW2, color black FW2
V, color black FW18, color black FW20
0, color black S150, color black S16
0, color black S170, PRINTEX (Pri
ntex) 35, PRINTEX U, PRINTEX V, PRINTEX 140U, PRINTEX 140
V, Special Black (SpecialBlack)
6, Special Black 5, Special Black 4A,
Special Black 4 (from Degussa), No. 2
5, no. 33, no. 40, no. 47, no. 5
2, No. 900, No. 2300, MCF-88, M
A600, MA7, MA8, MA100 (produced by Mitsubishi Chemical Corporation) and the like can be used, but not limited thereto, and conventionally known carbon black can be used. Further, magnetic fine particles such as magnetite and ferrite, titanium black and the like may be used as a black pigment.

(Organic pigment) As the organic pigment, specifically,
Insoluble azo pigments such as Toluidine Red, Toluidine Maroon, Hansa Yellow, Benzidine Yellow, and Pyrazolone Red, soluble azo pigments such as Litol Red, Helio Bordeaux, Pigment Scarlet, and Permanent Red 2B, vat dyeing such as alizarin, indanthrone, and thioindigo maroon Derivatives from dyes, phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green; quinacridone pigments such as quinacridone red and quinacridone magenta; perylene pigments such as perylene red and perylene scarlet; isoindolinone yellow and isoindolinone orange Indolinone pigments, imidazolone pigments such as benzimidazolone yellow, benzimidazolone orange and benzimidazolone red, pyrans Pyranthrone-based pigments such as red, pyranthrone orange, thioindigo-based pigments, condensed azo-based pigments, thioindigo-based pigments, flavanthrone yellow, acylamide yellow, quinophthalone yellow, nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, Dianthraquinonyl red,
Other pigments such as dioxazine violet can be exemplified.

In addition, the organic pigment was used as a color index (C.I.
I.) Indicated by number, CI Pigment Yellow 12,
13, 14, 17, 20, 24, 74, 83, 869
3, 109, 110, 117, 120, 125, 13
7, 138, 147, 148, 151, 153, 15
4, 166, 168, CI Pigment Orange 16,3
6, 43, 51, 55, 59, 61, CI Pigment Red 9, 48, 49, 52, 53, 57, 97, 12
2,123,149,168,175,176,17
7, 180, 192, 215, 216, 217, 22
0, 223, 224, 226, 227, 228, 23
8, 240, CI Pigment Violet 19, 23,
29, 30, 37, 40, 50, CI Pigment Blue 15, 15: 1, 15: 4, 15: 6, 22, 60, 6
4, CI Pigment Green 7, 36, CI Pigment Brown 23, 25, 26 and the like. Of course, in addition to the above, conventionally known organic pigments can be used.

(Dispersant) When the above-mentioned carbon black or organic pigment is used, it is preferable to use a dispersant in combination. As the dispersant, a dispersant capable of stably dispersing the above pigment in an aqueous medium by the action of an anionic group is suitably used. Specific examples of the dispersant include, for example, styrene-acrylic acid copolymer, styrene-acrylic acid-alkyl acrylate copolymer, styrene-maleic acid copolymer, styrene-maleic acid-alkyl acrylate copolymer, Styrene-methacrylic acid copolymer, styrene-methacrylic acid-alkyl acrylate copolymer, styrene-maleic acid half ester copolymer, vinyl naphthalene-acrylic acid copolymer, vinyl naphthalene-maleic acid copolymer, styrene -Maleic anhydride-maleic acid half ester copolymer or salts thereof. These dispersants preferably have a weight-average molecular weight in the range of 1,000 to 30,000, particularly preferably in the range of 3,000 to 15,000.

(Self-dispersing pigment) As a coloring material, a pigment which can be dispersed in an aqueous medium without a dispersant by binding an ionic group (anionic group) to the pigment surface, that is, a so-called self-dispersing pigment is used. For example, self-dispersion type carbon black can be mentioned as an example of such a pigment.

Examples of the self-dispersible carbon black include those in which an anionic group is bonded to the surface of the carbon black.

(Anionic CB) As the anionic carbon black, for example, -C
_{OO (M2), - SO 3} (M2), - PO 3 H (M2),
—PO ₃ (M2) ₂ to which at least one anionic group selected from the group is bonded.

In the above formula, M2 represents a hydrogen atom, an alkali metal, ammonium or organic ammonium. R
Represents an alkyl group having 1 to 12 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted naphthyl group. Among them, especially -COO (M2) and -S
Carbon black which is anionically charged by bonding O ₃ (M2) to the surface of the carbon black is particularly suitable for use in the present embodiment because of its good dispersibility in the ink. Incidentally, among the hydrophilic groups represented as “M2”, specific examples of the alkali metal include, for example, Li,
Na, K, Rb, and Cs. Specific examples of the organic ammonium include, for example, methyl ammonium,
Examples thereof include dimethyl ammonium, trimethyl ammonium, ethyl ammonium, diethyl ammonium, triethyl ammonium, methanol ammonium, dimethanol ammonium, and trimethanol ammonium. The ink of the present embodiment including the self-dispersion type carbon black in which M2 is ammonium or organic ammonium can further improve the water resistance of the recorded image, and can be particularly preferably used in this regard. This is considered to be due to the effect that when the ink is applied on the recording medium, ammonium is decomposed and ammonia is evaporated. Here, the self-dispersion type carbon black in which M2 is ammonium is prepared by, for example, a method of substituting M2 with ammonium by using an ion exchange method for a self-dispersion carbon black in which M2 is an alkali metal, or after adding an acid to form H-type. Add ammonium hydroxide to add M
And the like.

Examples of a method for producing self-dispersible carbon black charged anionic include a method of oxidizing carbon black with sodium hypochlorite.
Na groups can be chemically bonded.

By the way, various hydrophilic groups as described above are
It may be directly bonded to the surface of carbon black. Alternatively, another atomic group may be interposed between the carbon black surface and the hydrophilic group, and the hydrophilic group may be indirectly bonded to the carbon black surface. Here, specific examples of the other atomic groups include a linear or branched alkylene group having 1 to 12 carbon atoms, a substituted or unsubstituted phenylene group, and a substituted or unsubstituted naphthylene group.
Here, examples of the substituent of the phenylene group and the naphthylene group include a linear or branched alkyl group having 1 to 6 carbon atoms. As specific examples of the combination of another atomic group and the hydrophilic group, for example, _{-C 2 H 4 COO (M2)} ,
—Ph—SO ₃ (M2), —Ph—COO (M2) and the like (where Ph represents a phenyl group).

In the present embodiment, two or more of the above-described self-dispersible carbon blacks may be used as a color material of an ink appropriately selected. The amount of the self-dispersible carbon black in the ink is 0.1 to 15% by weight, particularly 1 to 15% by weight based on the total weight of the ink.
It is preferred to be in the range of 10% by weight. Within this range, the self-dispersion type carbon black can maintain a sufficiently dispersed state in the ink. Further, a dye may be added as a coloring material in addition to the self-dispersion type carbon black for the purpose of adjusting the color tone of the ink.

(Compatibility between Self-dispersing CB and Salt) Among the various self-dispersing carbon blacks described above, as a hydrophilic group on the surface of the carbon black, for example, -COO (M
_{2), - SO 3 (M2} ), - PO 3 H (M2), - PO 3
When (M2) ₂ is used, ammonium or organic ammonium can be preferably used as M2 as described above, but the salts to be combined at this time are M1 and M2.
It is preferable to match with. That is, in the process of studying the effect of adding a salt to the ink containing the self-dispersing carbon black, the present inventors made the hydrophilic group M2 (counter ion) and M1 of the self-dispersing carbon black the same. At times, it was found that the stability of the ink was particularly improved. The reason why such an effect can be obtained by aligning M1 and M2 is not clear, but salt exchange does not occur between the counter ion of the hydrophilic group of the self-dispersible carbon black and the salt in the ink. It is assumed that the dispersion stability of the self-dispersion type carbon black is stably maintained.

When both M1 and M2 are ammonium or organic ammonium, the water resistance of the recorded image can be further improved in addition to the effect of stabilizing the ink characteristics. In this case, when Ph-COO (NH ₄ ) (ammonium benzoate) is used as the salt in the ink, an extremely excellent result can be obtained in terms of the re-discharge property of the ink from the head nozzles after the inkjet recording is temporarily stopped. be able to.

(Colored fine particles / microencapsulated pigment)
In addition to the above-described coloring materials, pigments microencapsulated with a polymer or the like, colored fine particles in which resin particles are coated with a coloring material, and the like can be used.

The microcapsules inherently have dispersibility in an aqueous medium, but the above-mentioned dispersant may be further co-present in the ink in order to enhance the dispersion stability. When the colored fine particles are used as a coloring material, it is preferable to use the above-described anionic dispersant or the like.

(Aqueous Medium) The aqueous medium in which the colorant as described above is dispersed is not particularly limited, and the same aqueous medium as described above can be used as the aqueous medium used in the liquid composition. When the color ink is applied to a recording medium by an ink-jet method (for example, a bubble jet (registered trademark) method), the ink has a desired viscosity and surface tension so as to have excellent ink-jet discharge characteristics as described above. It is preferable to prepare as follows.

(Ink Set) The color tone of the ink constituting the ink set in combination with the liquid composition is not particularly limited, and for example, shows one color tone selected from yellow, magenta, cyan, red, green, blue and black. Ink may be used. Specifically, it can be used by appropriately selecting from the above-mentioned color materials so as to obtain an ink having a desired color tone.

Further, the ink to be combined with the liquid composition is not limited to one kind, and an ink set suitable for forming a multicolor image may be formed by combining two or more inks having different color tones. In this case, of the two or more inks, at least one of the inks exhibits a solid-liquid separation accelerated by interaction with the liquid composition, and the coloring material is dispersed in the aqueous medium by the action of the ionic group. As long as it is an ink, another ink may be an ink containing a dye as a coloring material, and of course, all inks may be inks in which the coloring material is dispersed in an aqueous medium by the action of an ionic group. According to such an ink set, bleeding when inks of different colors are applied adjacently on a recording medium, which is a problem when a multicolor image is formed by an inkjet apparatus, can be suppressed. More specifically, the bleeding which is a problem in the inkjet multi-color image includes a black ink and another color ink (for example, at least one ink selected from a yellow ink, a magenta ink, a cyan ink, a red ink, a green ink, and a blue ink). Ink) is likely to be particularly noticeable. Therefore, in this embodiment, a black ink is used as an ink in which a coloring material is dispersed by the action of an ionic group in an aqueous medium so as to interact with the liquid composition. It is preferable to combine them. The other color ink may be an ink in which a dye is dissolved in an aqueous medium, or of course, like a black ink, an ink in which a coloring material is dispersed in an aqueous medium by the action of an ionic group.

(Color Ink) As the dye used as a coloring material of the ink, a conventionally known dye can be used.
For example, an acid dye, a direct dye, a disperse dye, or the like can be used. For example, as the anionic dye, any of existing dyes and newly synthesized dyes can be used as long as they have appropriate color tone and density.
It is also possible to use a mixture of any of these. Specific examples of the anionic dye are shown below.

(Coloring Material for Yellow) C.I. I. Direct yellow 8, 11, 12, 27,
28, 33, 39, 44, 50, 58, 85, 86, 8
7, 88, 89, 98, 100, 110, 132 C.I. I. Acid Yellow 1, 3, 7, 11, 17,
23, 25, 29, 36, 38, 40, 42, 44, 7
6, 98, 99 C.I. I. Reactive Yellow 2, 3, 17, 2
5, 37, 42 C.I. I. Food yellow 3

(Coloring Material for Red) C.I. I. Direct Red 2, 4, 9, 11, 20,
23, 24, 31, 39, 46, 62, 75, 79, 8
0, 83, 89, 95, 197, 201, 218, 22
0, 224, 225, 226, 227, 228, 22
9, 230 C.I. I. Acid Red 6, 8, 9, 13, 14, 1
8, 26, 27, 32, 35, 42, 51, 52, 8
0, 83, 87, 89, 92, 106, 114, 11
5, 133, 134, 145, 158, 198, 24
9, 265, 289 C.I. I. Reactive Red 7, 12, 13, 1
5, 17, 20, 23, 24, 31, 42, 45, 4
6, 59 C.I. I. Food Red 87, 92, 94

(Coloring material for blue) C.I. I. Direct Blue 1, 15, 22, 25, 4
1, 76, 77, 80, 86, 90, 98, 106, 1
08, 120, 158, 163, 168, 199, 22
6 C. I. Acid Blue 1, 7, 9, 15, 22, 2
3, 25, 29, 40, 43, 59, 62, 74, 7
8, 80, 90, 100, 102, 104, 117, 1
27, 138, 158, 161 C.I. I. Reactive Blue 4, 5, 7, 13, 1
4, 15, 18, 19, 21, 26, 27, 29, 3,
2, 38, 40, 44, 100

(Coloring Material for Black) C.I. I. Direct Black 17, 19, 22, 3
1, 32, 51, 62, 71, 74, 112, 113,
154, 168, 195 C.I. I. Acid Black 2, 48, 51, 52, 1
10, 115, 156 C.I. I. Food black 1,2

Here, the content of the coloring material in each color ink can be appropriately selected, for example, when used for ink jet recording so that the ink has excellent ink jet discharge characteristics and has a desired color tone and density. As a guide, a range of, for example, 3 to 50% by weight based on the total weight of the ink is preferable. The amount of water contained in the ink is preferably in the range of 50 to 95% by weight based on the total weight of the ink.

(Recording method) The liquid composition is combined with an ink in which a coloring material is dispersed in an aqueous medium by the action of an ionic group, and (i) a step of applying the ink to a recording medium; ii) applying the liquid composition to at least an area of the recording medium to which the ink is applied;
By using the recording method having the above, an ink set capable of obtaining an image with high image density and high color development and good print quality can be provided. It is not clear why such an ink set can improve print quality with high image density and high color development, but, for example, the liquid composition and the ink were allowed to fly on paper by an inkjet method, and both were adhered. In this case, it is considered that the coloring material such as a pigment is stably dispersed and dissolved in the ink, but the solid-liquid separation after adhering to the paper surface occurs quickly. That is, if the solid-liquid separation is slow, the ink will diffuse into the paper on paper having high permeability. As a result, character sharpness (character quality)
At the same time, the image density naturally decreases because the ink penetrates deep into the paper. However, the solid-liquid separation of the ink according to the present embodiment occurs quickly, and thus it is considered that the above-described phenomenon is unlikely to occur even with paper having relatively high permeability. In other words, it is considered that factors such as the size of the permeability and the like are less likely to be affected. Further, it is naturally conceivable that the speed of the solid-liquid separation speeds up the fixability to the recording medium.

When the ink set of the ink and the liquid composition is used by an ink jet or the like, a: When printing the ink after printing the liquid composition,
b: When printing the liquid composition after printing the ink,
c: Various printing methods are conceivable, such as printing the liquid composition after printing the ink and then printing the ink.
The method of hitting the ink and the liquid composition may be appropriately selected according to, for example, the required print quality. For example, in the printing method a, particularly, the print quality can be improved. The reason is considered as follows according to the studies by the inventors so far. That is, in the printing method a, first, the liquid composition 91 is applied to the recording medium 25 (see FIG. 8A), and then the ink 92 is applied to the portion where the liquid composition has been applied (FIG. b)). Therefore, the color material in the ink undergoes solid-liquid separation due to the interaction with the salt in the liquid composition present on the surface of the recording material immediately after being applied to the recording medium 25. As a result, it is considered that more color material in the ink can be retained on the surface of the recording medium 25, and as a result, excellent printing results with extremely little blur and high density can be obtained.

Further, by combining a plurality of ink sets of the above liquid composition and color inks, or combining an ink set of the above liquid composition and color inks with other color inks, an ink which can be suitably used for forming a color image. We can provide sets. When such an ink set is used to perform recording adjacent to a black image portion and a color image portion using, for example, the above-described ink set for black ink, occurrence of bleeding can be extremely effectively suppressed. The reason why such an ink set can effectively suppress bleeding is not clear, but as a result of the solid-liquid separation after the ink set of the black ink adheres to the recording medium and the subsequent solidification of the colorant, It is considered that the black ink hardly oozes out to the color ink side at the boundary of the color image.

(Ink characteristics; inkjet discharge characteristics,
The ink set according to each of the above embodiments can be suitably used as an ink set for inkjet recording. Ink jet recording methods include a recording method in which mechanical energy is applied to ink to eject droplets, and a recording method in which thermal energy is applied to ink to eject droplets by bubbling of the ink. The liquid compositions and inks of the invention are particularly suitable for the method. When the liquid composition and the ink according to the above embodiments are used for ink jet recording, it is preferable that the liquid composition and the ink have characteristics capable of being ejected from an ink jet head. From the viewpoint of dischargeability from the inkjet head, the properties of the liquid include, for example, a viscosity of 1 to 15
cps, surface tension is 25 mN / m (dyne / cm) or more, especially viscosity is 1 to 5 cps, and surface tension is 25 to 50.
It is preferably set to mN / m (dyne / cm).

(Inkjet Recording Technology) Next, an ink jet recording technology that can suitably use each of the liquid compositions and inks of the present embodiment will be described.

FIGS. 1 and 2 show an example of the configuration of a head which is a main part of an apparatus utilizing thermal energy as an ink jet recording apparatus.

FIG. 1 is a sectional view of the head 13 along the ink flow path, and FIG. 2 is a sectional view taken along the line AB in FIG. The head 13 is obtained by bonding a heating element substrate 15 to a glass, ceramic, silicon or plastic plate having a flow path (nozzle) 14 through which ink passes. The heating element substrate 15 includes a protective layer 16 formed of silicon oxide, silicon nitride, silicon carbide, or the like, and electrodes 17-1, 17-2, HfB2, TaN, TaAl, or the like formed of aluminum, gold, an aluminum-copper alloy, or the like. Heat generating resistor layer 18 formed of a high melting point material, heat storage layer 19 formed of thermally oxidized silicon, aluminum oxide, etc., and substrate 20 formed of a material having good heat dissipation properties such as silicon, aluminum, aluminum nitride, etc. It is made up.

When a pulse-like electric signal is applied to the electrodes 17-1 and 17-2 of the head, the area indicated by n of the heating element substrate 15 rapidly generates heat, and the ink in contact with the surface is Bubbles are generated, the meniscus 23 protrudes due to the generated pressure, and the ink is ejected through the nozzles 14 of the head, becomes ink droplets 24 from the ejection orifices 22, and flies toward the recording material 25.

FIG. 3 is an external view of a multi-head in which many heads shown in FIG. 1 are arranged. This multi-head is formed by bonding a glass plate 27 having a multi-nozzle 26 and a heating head 28 similar to that described in FIG.

(Ink Jet Recording Apparatus) FIG. 4 shows an example of an ink jet recording apparatus incorporating this head. In FIG. 4, reference numeral 61 denotes a blade as a wiping member.
One end of which is held and fixed by a blade holding member, and forms a cantilever. Blade 61
Is arranged at a position adjacent to the recording area of the recording head 65, and in this example, is held in a form protruding into the movement path of the recording head 65.

Reference numeral 62 denotes a cap on the surface of the protrusion of the recording head 65, which is disposed at a home position adjacent to the blade 61 and moves in a direction perpendicular to the moving direction of the recording head 65.
A configuration is provided in which the capping is performed in contact with the ink ejection port surface. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61. Like the blade 61, the ink absorber is held in a form protruding into the movement path of the recording head 65. Blade 6 above
1, the ejection recovery unit 6 by the cap 62 and the ink absorber 63
4, the blade 61 and the ink absorber 63 remove moisture, dust and the like from the ejection port surface. In addition, each ink of the recording head and ink located at the discharge port of the liquid composition are sucked by a pump (not shown) through a cap, and the original ink of the recording head, or the ink and the liquid composition are sucked. And a recovery system unit for recovering the original discharge performance of the apparatus. In the case where an ink set as in the present invention is used and both the liquid composition and the ink are ejected by an ink jet apparatus, it is not necessary to separately provide a recovery system for the ink and the liquid composition.
Because, as described above, the liquid composition and the ink in which the coloring material is dispersed in the aqueous medium using the ionic group do not react simply by being mixed, the recovery of the liquid composition and the ink does not occur. This is because even if the system is shared, the function of the recovery system is not impaired over time.

Reference numeral 65 denotes a recording head which has discharge energy generating means and performs recording by discharging ink on a recording material opposed to a discharge port surface provided with discharge ports, and 66 includes a recording head 65 mounted thereon. This is a carriage for moving the recording head 65. The carriage 66 is slidably connected to a guide shaft 67, and a part of the carriage 66 is connected to a belt 69 driven by a motor 68 (not shown). This allows the carriage
66 can be moved along the guide shaft 67, and the recording head
The movement of the recording area and the area adjacent to the recording area according to 65 becomes possible. Reference numeral 51 denotes a paper feed unit for inserting a recording material, and reference numeral 52 denotes a paper feed roller driven by a motor (not shown).

With these arrangements, the recording material is fed to a position facing the discharge port surface 65 of the recording head, and is discharged to a discharge section provided with a discharge roller 53 as recording proceeds. In the above configuration, when the recording head 65 finishes recording and returns to the home position, the cap 62 of the ejection recovery unit 64 is retracted from the moving path of the recording head 65, but the blade 61 is moved in the moving path. It is protruding. As a result, the ejection openings of the recording head 65 are wiped. The cap 62 is the recording head
When capping is performed by contacting the ejection surface of the print head 65, the cap 62 moves so as to protrude into the movement path of the recording head. When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are at the same position as the position at the time of the wiping described above. As a result,
Also in this movement, the ejection port surface of the recording head 65 is wiped.

The movement of the print head to the home position is not only at the end of printing or at the time of ejection recovery, but also at a predetermined interval while the printing head moves through the printing area for printing. The wiping is performed in accordance with the movement.

(Ink Cartridge) FIG. 5 shows an example of a member for supplying an ink or a liquid composition to a recording head, for example, a cartridge 45 containing the ink or the liquid composition supplied via a tube. FIG. Here, reference numeral 40 denotes a storage section storing the supply ink or liquid composition, for example, a bag, and a rubber stopper 42 is provided at the tip thereof. By inserting a needle (not shown) into the stopper 42, the ink or liquid composition in the bag 40 can be supplied to the head. 44 is an absorber for receiving the waste ink or waste liquid composition. The container 40 preferably has a liquid contact surface with the ink or liquid composition formed of polyolefin, particularly polyethylene. Such a cartridge is configured to be detachable from a recording head 901 for ejecting ink or a liquid composition, for example, as shown in FIG. 9, and the ink or liquid composition is mounted when the cartridge 45 is mounted on the recording head. An object is supplied to the recording head 901.

In another aspect of the cartridge according to the present invention, there is provided a head for ejecting the ink and the liquid composition, which has two storage sections for individually storing the liquid composition and the ink. And a cartridge configured to be detachable from the recording head and configured to be able to supply the ink and the liquid composition to the recording head.

FIG. 10 shows such a cartridge 1001.
1003 is a liquid composition storage section, 1005 is an ink storage section, and the cartridge is a recording head 1101 for discharging each of the ink and the liquid composition as shown in FIG. The liquid composition and the ink are supplied to the recording head 1101 when the cartridge 1001 is mounted on the recording head 1101.

The ink set of the present invention is not limited to the one in which the liquid composition and the ink are physically integrated as shown in FIG. 10, but also, for example, as shown in FIG.
A cartridge 1201 containing the liquid composition and a cartridge 1203 containing the ink are shared by a common recording head 120 for ejecting the liquid composition and the ink, respectively.
5 is also included in the scope of the present invention so that an ink jet image can be recorded using the liquid composition and the ink.

(Recording Unit) The ink jet apparatus used in the present invention is not limited to the one in which the head and the cartridge are separated as described above, but they are integrated as shown in FIG. It is also suitably used for those which have been used. Figure 6
In the figure, reference numeral 70 denotes a recording unit, which is a storage unit for storing ink or a liquid composition. For example, when storing ink, an ink absorber is stored, and ink in the ink absorber is ejected as ink droplets from a head unit 71 having a plurality of orifices. It is preferable for the present invention to use polyurethane as the material of the ink absorber.

Further, a structure may be used in which the storage section is a bag in which a spring or the like is charged inside without using an absorber. Reference numeral 72 denotes an atmosphere communication port for communicating the inside of the cartridge with the atmosphere. This recording unit 70 is used in place of the recording head 65 shown in FIG. 4, and is detachable from the carriage 66.

In another embodiment of the recording unit according to the present invention, the liquid composition and at least one color ink selected from the group consisting of black, yellow, magenta, cyan, red, green, blue and black hues.
And a recording unit integrally containing a recording head for storing one ink in each ink storage part in one ink tank and discharging each ink, specifically, for example, shown in FIG. 1301 L of the liquid composition
, The black ink dispersed in the aqueous medium by the ionic group is stored in the storage portion 1301Bk, and the yellow, cyan and magenta color inks are stored in the color ink storage portions 1301Y, 1301C and 1301M, respectively. There is a recording unit 1301 including a recording head 1303 configured with separate ink flow paths so that an object and the other four inks having different tones can be ejected individually.

Next, as an embodiment of an ink jet recording apparatus utilizing the second mechanical energy, a nozzle forming substrate having a plurality of nozzles, and a pressure generating element made of a piezoelectric material and a conductive material disposed opposite to the nozzles And an on-demand ink jet recording head that includes ink filling around the pressure generating element, displaces the pressure generating element by an applied voltage, and discharges a small droplet of ink from a nozzle. FIG. 7 shows a configuration example of a recording head which is a main part of the recording apparatus.

The head includes an ink flow path 80 communicating with an ink chamber (not shown), an orifice plate 81 for discharging ink droplets of a desired volume, a vibration plate 82 for directly applying pressure to ink, and a It is composed of a pressure transmitting element 83 which is joined to the diaphragm 82 and is displaced by an electric signal, and a substrate 84 for pointing and fixing the orifice plate 81, the diaphragm and the like.

In FIG. 7, an ink flow path 80 is formed of a photosensitive resin or the like, and an orifice plate 81 has a discharge port 85 formed by electroforming or pressing a metal such as stainless steel or nickel. Plate 82 is stainless steel,
Nickel, formed of a metal film such as titanium and a high elastic resin film, etc., the piezoelectric element 83 is a barium titanate,
It is formed of a dielectric material such as PZT. The recording head configured as described above applies a pulse-like voltage to the piezoelectric element 83 to generate a strain stress, and the energy deforms the diaphragm bonded to the piezoelectric element 83, causing the ink in the ink flow path 80 to deform. Is pressed vertically, and an ink droplet (not shown) is ejected from the ejection port 85 of the orifice plate to perform printing. Such a recording head is used by being incorporated in a recording apparatus similar to that shown in FIG. The detailed operation of the recording apparatus may be performed in the same manner as described above.

(Recording Apparatus and Recording Method Using Ink Set) Next, when a color image is recorded using the ink set, for example, five recording heads shown in FIG. The device can be used. FIG. 14 shows an embodiment of the invention, wherein 1401L, 1401Bk, 1
401Y, 1401M and 1401C are each the liquid composition,
Black ink containing carbon black dispersed in an aqueous medium by the action of an ionic group, and cyan,
A recording unit for ejecting magenta and yellow inks. The recording unit is disposed on the carriage of the above-described recording apparatus, and discharges ink of each color according to a recording signal. Further, the liquid composition is applied to a portion where the recording ink of each color or at least one of the colors adheres to the recording paper before or after the ink is applied. FIG. 14 shows an example in which five recording units are used. However, the present invention is not limited to this. For example, as shown in FIG. The inks of the respective colors supplied from the ink cartridges 1501L, 1501Bk, 1501Y, 1501M and 1501C containing the black ink containing the dispersed carbon black and the three color inks of YMC can be individually ejected. There is also a mode in which printing is performed by attaching to a print head 1501 configured with separate ink flow paths.

Next, another specific example of a recording apparatus and a recording head which can be suitably used in the present invention will be described. FIG. 16 is a schematic view of an example of an ink jet printer as a liquid discharge head and a liquid discharge apparatus using the head in which bubbles are communicated with the atmosphere when the liquid composition and the ink constituting the ink set according to the present invention are discharged. It is a schematic perspective view which shows a part.

In FIG. 16, the ink jet printer includes a transport device 1030 for intermittently transporting a sheet 1028 as a recording medium provided along a longitudinal direction in a casing 1008 in a direction indicated by an arrow P shown in FIG. A recording unit 1010 that is reciprocated substantially in parallel to a direction S substantially perpendicular to the conveyance direction P of the paper 1028 by the conveyance device 1030;
And a movement drive unit 1006 as drive means for reciprocating the recording unit 1010.

The movement driving unit 1006 is provided with pulleys 1026a and
A belt 1016 wound around 1026b and a recording unit 101 arranged substantially parallel to the roller units 1022a and 1022b.
And a motor 1018 for driving a belt 1016 connected to the carriage member 1010a in the forward and reverse directions.

When the motor 1018 is activated and the belt 1
16 rotates in the direction of arrow R in FIG.
The carriage member 1010a is moved by a predetermined amount in the direction of arrow S in FIG. When the motor 1018 is activated and the belt 1016 rotates in the direction opposite to the direction of arrow R in FIG. 16, the carriage member 101 of the recording unit 1010 is rotated.
0a is moved by a predetermined amount of movement in the direction opposite to the direction of arrow S in FIG. In addition, the movement drive unit 100
At one end of the recording unit 1010, a recovery unit 1026 for performing an ejection recovery process of the recording unit 1010 is provided at a position to be a home position of the carriage member 1010a so as to face the ink ejection port arrangement of the recording unit 1010.

The recording unit 1010 is an ink jet cartridge (hereinafter, sometimes simply referred to as a cartridge).
12Y, 1012M, 1012C, and 1012B are detachably provided for the carriage member 1010a for each color, for example, yellow, magenta, cyan, and black.

FIG. 17 shows an example of an ink jet cartridge that can be mounted on the above-described ink jet recording apparatus.
The cartridge 1012 in this example is of a serial type, and its main part is composed of an ink jet recording head 100 and a liquid tank 1002 for storing a liquid such as ink.

The ink jet recording head 100 has a large number of ejection ports 832 for ejecting liquid.
Liquid such as ink is supplied from the liquid tank 1002 to a common liquid chamber of the liquid ejection head 100 through a liquid supply passage (not shown).
(See FIG. 18). The cartridge 1012 integrally forms the ink jet recording head 100 and the liquid tank 1001 so that the liquid can be supplied to the liquid tank 1001 as needed. Tank 100
A structure in which 1 are exchangeably connected may be adopted.

A specific example of the above-described liquid discharge head that can be mounted on the ink jet printer having such a configuration will be described in more detail below.

FIG. 18 is a schematic perspective view schematically showing a main part of a liquid discharge head showing a basic form of the present invention, and FIGS. 19 to 22 show discharge port shapes of the liquid discharge head shown in FIG. FIG. Note that electrical wiring and the like for driving the electrothermal transducer are omitted.

In the liquid ejection head of this example, a substrate 934 made of glass, ceramics, plastic, metal or the like is used as shown in FIG. The material of such a substrate is not the essence of the present invention,
It is not particularly limited as long as it functions as a part of the flow path constituent member, and can function as a support of a material layer forming an ink discharge energy generating element, and a liquid flow path and a discharge port described later. Absent. Therefore, in this example, the Si substrate
(Wafer) will be described. In addition to the forming method using laser light, for example, an orifice plate (discharge port plate)
It can also be formed by an exposure apparatus such as A (Mirror Projection Aligner).

In FIG. 18, reference numeral 934 denotes an electrothermal transducer.
(Hereinafter, it may be described as a heater.) 931 and an ink supply port 9 composed of a long groove-shaped through hole as a common liquid chamber portion
The heaters 931 serving as thermal energy generating means are arranged in a row in a zigzag pattern on both sides of the ink supply port 933 in the longitudinal direction, for example, at 300 dpi intervals. On the substrate 934, an ink flow path wall 936 for forming an ink flow path is provided. The ink flow path wall 936 is further provided with a discharge port plate 935 having a discharge port 832.

Here, in FIG.
36 and the discharge port plate 935 are shown as separate members, but the ink flow path wall 936 and the discharge port plate 935 are formed on the substrate 934 by a method such as spin coating. Can be formed simultaneously as the same member. In this example, the ejection port surface (upper surface) 935a side is further subjected to a water-repellent treatment.

In this example, a serial type head that performs recording while scanning in the direction of arrow S in FIG. 16 is used to perform recording at, for example, 1200 dpi. The driving frequency is 10 kHz, and one ejection port performs ejection at a minimum time interval of 100 μs.

As an example of the actual dimensions of the head,
For example, as shown in FIG. 19, a partition wall 936a that fluidly isolates adjacent nozzles has a width w = 14 μm. As shown in FIG. 22, the foaming chamber 1337 formed by the ink flow path wall 936 has N ₁ (width of the foaming chamber) = 33 μm, N
₂ (length of foaming chamber) = 35 μm. Heater 931
Is 30 μm in size, the heater resistance is 53Ω, and the driving voltage is 10.3V. Further, the height of the ink flow path wall 936 and the partition wall 936a is 12 μm, and the thickness of the discharge port plate is 11 μm.

In the cross section of the discharge port portion 940 provided on the discharge port plate including the discharge port 832, the ink discharge direction
The cross section taken along a direction intersecting (thickness direction of the orifice plate 935) has a substantially star-shaped cross section, and includes six raised portions 832a having obtuse angles and these raised portions 83
2a, and is formed roughly by six ridges 832b alternately arranged and having acute angles. That is, the recess 832 as a region locally separated from the center O of the discharge port
b as its top and a base 832a as a region locally close to the center O of the discharge port adjacent to this region, and six grooves in the thickness direction (liquid discharge direction) of the orifice plate shown in FIG. Are formed.

(Refer to 1141a in FIG. 23 for the position of the groove.) In this example, the discharge port 940 is formed by rotating two equilateral triangles having a side of 27 μm along a direction crossing the thickness direction by 60 degrees. The shapes are combined in the state where they are made, and T ₁ shown in FIG. 20 is 8 μm.
The angles of the raised portions 832a are all 120 degrees,
The angles of 2b are all 60 degrees.

Therefore, it is formed by connecting the center O of the discharge port and the center of the groove adjacent to each other (the center (center of gravity) of the figure formed by connecting the top of the groove and the two bases adjacent to the top). And the center of gravity G of the polygon.
The opening area of the discharge port 832 in this example is 400 μm ² ,
The opening area of the groove (the area of the figure formed by connecting the top of the groove and the two bases adjacent to the top) is about 3 per one.
3 μm ² .

FIG. 21 is a schematic diagram showing the state of ink adhesion at the ejection port shown in FIG.

Next, the operation of discharging the liquid by the ink jet recording head having the above-described configuration will be described with reference to FIGS.

FIGS. 23 to 30 are cross-sectional views for explaining the liquid discharging operation of the liquid discharging head shown in FIGS. 18 to 22, and are XX cross-sectional views of the foaming chamber 1337 shown in FIG. 2215. . In this cross section, the end of the discharge port 940 in the thickness direction of the orifice plate is the top 1141a of the groove 1141.
It has become.

FIG. 23 shows a state in which film-like air bubbles have been generated on the heater. FIG. 24 shows about 1 μs after FIG. 23, FIG. 25 shows about 2 μs after FIG. 23, FIG. 26 shows about 3 μs after FIG. FIG.
7 is about 4 μs of FIG. 23, and FIG. 28 is about 5 μs of FIG.
FIG. 29 shows the state after about 6 μs in FIG. 23, and FIG. 30 shows the state after about 7 μs in FIG. In the following description, "fall" or "drop" does not mean "drop in the direction of gravity", and does not mean movement in the direction of the electrothermal transducer regardless of the mounting direction of the head. Say.

First, as shown in FIG. 23, when air bubbles 101 are generated in the liquid flow path 1338 on the heater 931 due to energization of the heater 931 based on a recording signal or the like, about 2 μm
During s, as shown in FIGS. 24 and 25, the volume rapidly expands and grows. The height of the bubble 101 at the maximum volume is higher than the discharge port surface 935a, but at this time, the pressure of the bubble has been reduced from a fraction of the atmospheric pressure to a fraction of the atmospheric pressure.

Next, at about 2 μs after the generation of the bubble 101, the bubble 101 starts to decrease in volume from the maximum volume as described above, and almost at the same time, the formation of the meniscus 102 starts. The meniscus 102 also recedes, that is, falls in the direction toward the heater 931 as shown in FIG.

[0111] Here, in the present embodiment, by having dispersed a plurality of grooves 1141 in the discharge port portion, when the meniscus 102 is retracted, the meniscus retraction direction F _M at a portion of the groove 1141 capillary force acts in an opposite direction F _C.
As a result, even if some variation in the state of the bubble 101 is recognized for some reason, the shape of the meniscus and the main droplet (hereinafter, sometimes referred to as liquid or ink) Ia at the time of meniscus retreat, The correction is made so as to be substantially symmetrical with respect to the center of the discharge port.

In this example, the meniscus 102
Is faster than the contraction speed of the bubble 101,
As shown in FIG. 27, at about 4 μs after the generation of the bubbles, the bubbles 101 communicate with the atmosphere near the lower surface of the discharge port 832. At this time, the liquid (ink) near the central axis of the ejection port 832 falls toward the heater 931. This is because the liquid (ink) Ia pulled back to the heater 931 side by the negative pressure of the bubble 101 before communicating with the atmosphere changes the bubble 10a.
This is because the inertia maintains the speed in the plane of the heater 931 even after the communication with the atmosphere.

The liquid (ink) which has dropped toward the heater 931 reaches the surface of the heater 931 at about 5 μs after the generation of the bubble 101 as shown in FIG. 28, and as shown in FIG. It spreads so as to cover the surface of the heater 931. The liquid spread so as to cover the surface of the heater 931 has a horizontal vector along the surface of the heater 931, but the vector that intersects with the surface of the heater 931, for example, the vector in the vertical direction disappears, and the heater 931 disappears.
1 and will pull downward the liquid above it, that is, the liquid that maintains the velocity vector in the ejection direction.

Thereafter, the liquid portion Ib between the liquid spread on the surface of the heater 931 and the liquid on the upper side (main droplet) becomes thinner, and at about 7 μs after the generation of the bubble 101, FIG.
As shown at 0, the liquid portion Ib is cut at the center of the surface of the heater 1 and separated into a main droplet Ia that maintains the velocity vector in the ejection direction and a liquid Ic that spreads on the surface of the heater 931. Thus, the separation position is desirably inside the liquid flow path 1338, more preferably on the electrothermal conversion element 931 side than the discharge port 832.

The main droplet Ia is discharged from the central portion of the discharge port 832 without deviation in the discharge direction and without being distorted, and lands at a predetermined position on the recording surface of the recording medium. Further, the liquid Ic spread on the surface of the heater 931 flies as a satellite droplet following the main droplet in the related art, but remains on the surface of the heater 931 and is not discharged.

Since the ejection of the satellite droplets can be suppressed in this manner, the splash which is easily generated by the ejection of the satellite droplets can be prevented, and the recording surface of the recording medium becomes dirty by the mist floating in the mist. Can be reliably prevented. 27 to 29, Id represents ink attached to the groove (ink in the groove), and Ie represents ink remaining in the liquid flow path.

As described above, in the liquid discharge head of this embodiment,
When the liquid is ejected at the volume reduction stage after the bubble has grown to the maximum volume, the direction of the main droplet at the time of ejection can be stabilized by the plurality of grooves dispersed with respect to the center of the ejection port. As a result, it is possible to provide a liquid ejection head with high landing accuracy, which has no deviation in the ejection direction. In addition, high-speed and high-definition printing can be realized because the ejection can be stably performed even when the bubbling varies at a high driving frequency.

In particular, by discharging the liquid by starting the bubble and communicating with the atmosphere at the stage of reducing the volume of the bubble, it is possible to prevent the mist generated when the bubble is discharged by connecting the bubble to the atmosphere. It is also possible to suppress a state in which droplets adhere to the ejection port surface, which is a cause of so-called sudden ejection failure.

As another embodiment of a recording head of a discharge system which can be suitably used in the present invention and which communicates air bubbles with the atmosphere at the time of discharge, for example, as described in Japanese Patent No. 2783647, a so-called edge shooter type Is mentioned.

The present invention particularly provides an excellent effect in an ink jet recording head and a recording apparatus in which a flying liquid droplet is formed by utilizing thermal energy and recording is performed.

The typical configuration and principle are described in, for example, US Pat. No. 4,723,129 and US Pat.
It is preferable to use the basic principle disclosed in Japanese Patent Application No. 0 796. This method can be applied to both the so-called on-demand type and the continuous type.
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling to an electrothermal transducer arranged corresponding to the sheet or liquid path in which The heat generated by the electrothermal transducer causes the film to boil on the heat-acting surface of the recording head.
This is effective because bubbles in (ink) can be formed. Due to the growth and shrinkage of this bubble, the liquid (ink)
To form at least one droplet. When this drive signal is formed into a pulse shape, the growth and shrinkage of the bubbles are performed immediately and appropriately, so that the liquid (ink) which has particularly excellent responsiveness
Discharge can be achieved, which is more preferable.

As the pulse-shaped driving signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, The present invention also includes a configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which a heat acting portion is arranged in a bending region.

In addition, JP-A-59-123670, which discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, or absorbs pressure waves of thermal energy. The present invention is also effective as a configuration based on JP-A-59-138461, which discloses a configuration in which the openings correspond to the discharge portions.

Further, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length is determined by combining a plurality of recording heads as disclosed in the above specification. The present invention can exhibit the above-mentioned effects more effectively, though it may be either a configuration that satisfies the above requirements or a configuration as a single recording head that is formed integrally.

In addition, the print head is replaceable with a print head of a replaceable chip type, which can be electrically connected to the main body of the apparatus or supplied with ink from the main body of the apparatus, or is integrated with the print head itself. The present invention is also effective when a cartridge type recording head provided with an ink tank is used.

It is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like provided as components of the printing apparatus of the present invention since the effects of the present invention can be further stabilized. If you list these specifically,
Capping means, cleaning means, pressurizing or suction means for the printhead, preheating means using an electrothermal transducer or another heating element or a combination thereof, and a preliminary ejection mode for performing ejection other than recording Is also effective for performing stable recording.

Further, the recording mode of the recording apparatus is not limited to a recording mode of only a mainstream color such as black, but may be an integral recording head or a combination of a plurality of recording heads. The present invention is also extremely effective for an apparatus provided with at least one of full colors by color mixture.

In the embodiments of the present invention described above,
Although the ink is described as a liquid, it is an ink that solidifies at room temperature or lower, and softens at room temperature, or is a liquid, or in the inkjet method described above, the ink itself is heated to 30 ° C or more and 70 ° C or less. Generally, the temperature is adjusted within the range and the temperature is controlled so that the viscosity of the ink is in the stable ejection range. Therefore, it is sufficient that the ink is in a liquid state when the use recording signal is applied.

In addition, the temperature rise due to thermal energy is positively prevented by using it as energy for changing the state of the ink from the solid state to the liquid state, or the ink is solidified in a standing state to prevent evaporation of the ink. Either ink may be used, or in any case, the ink may be liquefied by application of heat energy according to the recording signal and ejected as a liquid ink, or may already start to solidify when reaching the recording medium. The use of an ink having a property of being liquefied for the first time by thermal energy is also applicable to the present invention. In such a case, the ink is disclosed in JP-A-54-5684.
No. 7 or Japanese Patent Application Laid-Open No. 60-71260, in which the porous sheet is opposed to the electrothermal converter in a state of being held as a liquid or solid substance in the concave portions or through holes of the porous sheet. It is good. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as a form of the recording apparatus according to the present invention, in addition to those provided integrally or separately as an image output terminal of an information processing device such as a word processor or a computer, a copying apparatus combined with a reader, A facsimile apparatus having a transmission / reception function may be employed.

Next, an outline of a liquid ejection apparatus equipped with the above-described liquid ejection head will be described.

FIG. 31 is a schematic perspective view of an ink jet recording apparatus 600 which is an example of a liquid discharge apparatus to which the liquid discharge head of the present invention can be mounted.

In FIG. 31, an ink jet head cartridge 601 is formed by integrating the above-described liquid discharge head and an ink tank for holding ink to be supplied to the liquid discharge head. The inkjet head cartridge 601 is mounted on a carriage 607 that engages with a spiral groove 606 of a lead screw 605 that rotates via driving force transmission gears 603 and 604 in conjunction with forward and reverse rotation of a driving motor 602. The carriage 607 is reciprocated along the guide 608 by the power of the drive motor 602 in the directions of arrows a and b. The recording material P is transported on the platen roller 609 by a recording material transporting means (not shown), and is moved by the paper pressing plate 610 in the moving direction of the carriage 607.
9 is pressed.

In the vicinity of one end of the lead screw 605,
Photocouplers 611 and 612 are provided. These are home position detection means for confirming the presence of the lever 607a of the carriage 607 in this area and switching the rotation direction of the drive motor 602 and the like.

The support member 613 supports the cap member 614 which covers the front surface (ejection surface) of the above-described ink jet head cartridge 601 having the ejection openings.
Further, the ink suction means 615 is for suctioning the ink accumulated inside the cap member 614 after the idle discharge or the like from the inkjet head cartridge 601. The ink suction unit 615 allows the ink-jet head cartridge 601 to pass through an opening (not shown) in the cap.
Suction recovery is performed. A cleaning blade 617 for wiping the ejection port surface of the ink jet head cartridge 601 is provided so as to be movable in a front-rear direction (a direction perpendicular to the moving direction of the carriage 607) by a moving member 618. These cleaning blades 61
7 and the moving member 618 are supported by the main body support 619. The cleaning blade 617 is not limited to this mode, and may be another known cleaning blade.

In the suction recovery operation of the liquid discharge head, the lever 620 for starting suction moves with the movement of the cam 621 engaging with the carriage 607,
The movement of the driving force from the driving motor 602 is controlled by known transmission means such as clutch switching. An ink jet recording control unit for giving a signal to a heating element provided in the liquid ejection head of the ink jet head cartridge 601 and for controlling the driving of each mechanism described above is provided on the apparatus main body side. Not shown.

In the ink jet recording apparatus 600 having the above-described configuration, the recording medium P ′ conveyed on the platen roller 609 by the recording medium conveying means (not shown) is used for the ink jet head cartridge 601 to record the recording material P ′.
Recording is performed while reciprocating over the entire width of.

[0139]

The present invention will be described in more detail with reference to the following examples and comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In the following description, parts and percentages are by weight unless otherwise specified.

Liquid Composition The following components were mixed, sufficiently stirred and dissolved, and then subjected to pressure filtration with a micro filter having a pore size of 0.2 μm (manufactured by Fuji Film) to prepare a liquid composition. Sodium chloride 10 parts Trimethylolpropane 6 parts Glycerin 5 parts Diethylene glycol 5 parts Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH) 0.15 parts Water 73.85 parts

Pigment Dispersion The specific surface area is 220 m ² / g and the DBP oil absorption is 112 ml.
/ 100 g of carbon black 10 g and p-amino-N
-0.55 g of benzoic acid was mixed well with 72 g of water, and 1.62 g of nitric acid was added dropwise thereto, followed by stirring at 70 ° C. After a few more minutes, a solution of 1.07 g of sodium nitrite dissolved in 5 g of water was added, and the mixture was further stirred for 1 hour. The obtained slurry was filtered through filter paper (trade name: Toyo Filter Paper No. 2; manufactured by Advantis Co., Ltd.), and the pigment particles collected by filtration were sufficiently washed with water, dried in an oven at 90 ° C. Were added to prepare an aqueous pigment solution having a pigment concentration of 10% by weight. By the above method, a group represented by the following chemical formula was introduced into the surface of carbon black.

[0142]

[Outside 1]

Next, using the above pigment dispersion, a black ink was prepared by the following method.

(Black ink) The following components were mixed,
After sufficiently stirring and dissolving, the mixture was filtered under pressure with a micro filter having a pore size of 3.0 μm (manufactured by Fuji Film) to prepare a black ink. The above pigment dispersion 30 parts Trimethylol propane 6 parts Glycerin 5 parts Diethylene glycol 5 parts Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH) 0.15 parts Water 53.85 parts

Example 1 An on-demand type multi-recording head is provided in which the liquid composition and the black ink prepared above are combined as follows, and the ink is ejected by applying thermal energy to the ink in accordance with a recording signal. Inkjet recording device (trade name: BJC600; manufactured by Canon Inc.)
, Printing was performed by applying the liquid composition to and around the portion where the black ink was applied before applying the black ink. The time interval between the application of the liquid composition and the ink was about 30 milliseconds.

Example 2 An on-demand type multi-recording head for discharging the ink by applying the thermal energy according to the recording signal to the ink by combining the liquid composition and the black ink prepared above as follows. Inkjet recording device (trade name: BJC600; manufactured by Canon Inc.)
After the black ink was applied, printing was performed by applying the liquid composition to the black ink applied portion. The time interval between the application of the liquid composition and the ink was about 30 milliseconds.

Comparative Example 1 Printing was performed in the same manner as in Example 1 except that the liquid composition was not used.

The following evaluations were performed for Examples 1 and 2 and Comparative Example 1. Table 1 shows the results.

1) Printing Density The above inks were printed on the following plain paper for copying A, B, C, D, and E using the above-mentioned ink jet recording apparatus, and the printing density at that time was measured using a Macbeth printing density measuring device. It measured using and evaluated by the following reference | standard. And the obtained result was evaluated based on the following criteria. A: PPC paper manufactured by Canon Inc. NSK B: PPC paper manufactured by Canon Inc. NDK C: PPC paper manufactured by Xerox Co., Ltd. 4024 D: PPC paper prober bond manufactured by Fox River E: Neuzidora for Canon PPC paper (Plain paper A, B, C, D, and E for copying below shall all correspond to plain paper A, B, C, D, and E for copying.)-Evaluation standard of print density a; The difference between the print densities of the plain papers A, B, C, D, and E for copying is the maximum and the minimum is less than 0.1. b: Difference in print density between plain papers A, B, C, D, and E for copying is 0.1 or more at the highest and the lowest.

2) Character Quality The above-described plain papers A and A for copying each of the above-described inks having different ink permeability using the above-described ink jet recording apparatus.
Character printing was performed on B, C, D, and E, and the bleeding of the characters at that time was evaluated according to the following criteria. Further, in Example 1, the liquid composition was printed on the black ink printing portion before printing the black ink, and in Example 2, the liquid composition was printed on the black ink printing portion after printing the black ink. The obtained results were evaluated according to the following criteria. -Evaluation criteria of character quality a; b: Some blurred paper is seen. c; Bleed on all five papers.

3) Fixing properties The above-mentioned plain papers A, B, C, and C for copying were prepared using the above-mentioned inks by using the above-mentioned ink jet recording apparatus and having different ink permeability.
Printing was performed on D and E, and the printed matter at that time was rubbed by hand, and the time during which printing flow did not occur was measured and evaluated according to the following criteria. Further, in Example 1, the liquid composition was printed on the black ink printing portion before printing the black ink, and in Example 2, the liquid composition was printed on the black ink printing portion after printing the black ink. The obtained results were evaluated according to the following criteria. -Evaluation criteria of fixability a: There is almost no printing flow after 30 seconds for all five papers. b: Some paper is printed after 30 seconds. c: Paper with some printing after 40 seconds is seen.

[0152]

[Table 1]

As can be seen from the results in Table 1, the ink according to the embodiment of the present invention has high character quality and print density when recording is performed by, for example, an ink jet recording method.

Example 3 (Liquid composition) A liquid composition was prepared in the same manner as in the liquid composition of Example 1 above.

(Black Ink) A black ink adjusted in the same manner as the black ink of Example 1 was prepared.

Preservation Two glass containers each having a capacity of 100 ml (manufactured by Shot Co., Ltd.) were prepared, and 100 ml of the liquid composition of Example 3 and the black ink were placed in each of them. The presence or absence of a change in viscosity was observed. In addition,
The evaluation criteria are as follows. Here, in Example 3, if either of the liquid composition and the black ink shows a large change in viscosity, it is determined to be b. The results are shown in Table 2 below. -Evaluation criteria of storage stability a: There is almost no change in the viscosity of the ink or the liquid composition before and after standing. b: The change in viscosity of the ink or liquid composition before and after being left is large.

[0157]

[Table 2]

Example 4 (Liquid composition) A liquid composition was prepared in the same manner as in Example 1 above.

(Black Ink) A black ink adjusted in the same manner as the black ink of Example 1 was prepared.

(Yellow Ink 1) The following components were mixed, sufficiently stirred and dissolved, and then subjected to pressure filtration with a micro filter having a pore size of 0.2 μm (manufactured by Fuji Film) to prepare Yellow Ink 1. Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH) 1 part Diethylene glycol 10 parts Glycerin 5 parts CI Direct Yellow 86 3 parts Water 81 parts

(Magenta Ink 1) The following components were mixed, sufficiently stirred and dissolved, and then filtered under pressure through a micro filter having a pore size of 0.2 μm (manufactured by Fuji Film) to prepare Magenta Ink 1. Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH) 1 part Diethylene glycol 10 parts Glycerin 5 parts CI Acid Red 35 3 parts Water 81 parts

(Cyan Ink 1) The following components were mixed,
After sufficiently stirring and dissolving, cyan ink 1 was prepared by filtration under pressure with a micro filter having a pore size of 0.2 μm (manufactured by Fuji Film). Acetylene glycol ethylene oxide adduct (trade name: acetylenol EH) 1 part Diethylene glycol 10 parts Glycerin 5 parts CI acid blue 9 3 parts Water 81 parts

An ink set was prepared by combining the above-prepared inks as follows.・ Liquid composition ・ Black ink ・ Yellow ink ・ Magenta ink ・ Cyan ink

Comparative Example 2 (Black Ink) A black ink adjusted in the same manner as the black ink of Example 1 was prepared.

(Yellow Ink) A yellow ink prepared in the same manner as the yellow ink of Example 4 was prepared.

(Magenta Ink) A magenta ink adjusted in the same manner as the magenta ink of Example 4 was prepared.

(Cyan Ink) A cyan ink adjusted in the same manner as the cyan ink of Example 4 was prepared.

An ink set was prepared by combining the above-prepared inks as follows.

Black ink Yellow ink Magenta ink Cyan ink

An ink-jet recording apparatus BJF-800 having an on-demand type multi-recording head for ejecting ink by applying thermal energy according to a recording signal to the ink using the inks of Example 4 and Comparative Example 2 described above.
The bleeding was evaluated as follows using (manufactured by Canon). Table 3 shows the results.

Bleeding The printed image is a square of 10 cm square, divided by 5 × 5 squares (the size of one square: 2 cm × 2 cm), and solid printed alternately with black ink and each color ink. The bleeding at the boundary with the printed portion was evaluated according to the following criteria.

In Example 4, the liquid composition was solid-printed on the black ink printing portion before printing the black ink. -Evaluation criteria of bleeding a: The boundary between two colors is clear, and no bleeding or color mixing is observed at the boundary. b; Although it is clear that there is a boundary line between the two colors, some bleeding and color mixing are observed at the boundary portion on some papers. c: Borderline between two colors cannot be identified.

[0173]

[Table 3]

[0174]

As described above, according to each of the embodiments of the present invention, there is no need to worry about stability due to long-term storage in printing with black ink when performing ink-jet recording, and the influence of the printed matter is alleviated. An ink set having high quality and high print density, bleeding can be effectively suppressed when combined with a color ink, and an ink jet recording method and an ink jet recording apparatus using the ink can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view illustrating an example of a head of an inkjet recording apparatus.

FIG. 2 is a cross-sectional view illustrating an example of a head of the inkjet recording apparatus.

FIG. 3 is an external perspective view of a head obtained by multiplying the head shown in FIG. 1;

FIG. 4 is a schematic perspective view illustrating an example of an ink jet recording apparatus.

FIG. 5 is a longitudinal sectional view illustrating an example of an ink cartridge.

FIG. 6 is a perspective view illustrating an example of a recording unit.

FIG. 7 is a schematic cross-sectional view illustrating another configuration example of the inkjet recording head.

FIG. 8 is a schematic explanatory diagram of a recording method according to an embodiment of the present invention.

FIG. 9 is a schematic plan view showing a state where the ink cartridge according to one embodiment of the present invention is mounted on a recording head.

FIG. 10 is a schematic plan view showing another embodiment of the ink cartridge according to one embodiment of the present invention.

11 is a schematic plan view showing a state where the ink cartridge of FIG. 10 is mounted on a recording head.

FIG. 12 is a schematic plan view showing another embodiment of the ink set according to the present invention.

FIG. 13 is a schematic perspective view showing another embodiment of the recording unit according to the present invention.

FIG. 14 shows a recording unit containing a liquid composition, a recording unit containing a black ink containing a coloring material dispersed in an aqueous medium by the action of an ionic group, according to an embodiment of the ink set of the present invention, 6 is a schematic diagram showing a state in which recording units storing respective color inks of CMY and CMY are mounted on the same carriage.

FIG. 15 is an enlarged view of an orifice portion of one embodiment of the recording head portion of the ink jet device of FIG.

FIG. 16 is a schematic perspective view illustrating a main part of an example of an ink jet printer on which a liquid discharge head can be mounted.

FIG. 17 is a schematic perspective view showing an example of an inkjet cartridge provided with a liquid ejection head.

FIG. 18 is a schematic perspective view schematically showing a main part of an example of a liquid ejection head.

FIG. 19 is a conceptual diagram in which a part of an example of a liquid ejection head is extracted.

FIG. 20 is an enlarged view of a discharge port shown in FIG. 19;

FIG. 21 is a schematic diagram illustrating a state of ink adhesion at a discharge port illustrated in FIG. 20;

FIG. 22 is a schematic diagram of a main part in FIG. 19;

23 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 31 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIGS. 4 to 30.

24 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 31 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIG. 3 and FIGS.

25 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 3 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time, together with FIGS. 3, 24, and 26 to 30.

26 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 31 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIGS. 3 to 25 and FIGS. 27 to 30.

27 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 31 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIGS. 3 to 26 and FIGS. 28 to 30.

28 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 31 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIGS. 3 to 27 and FIGS. 29 and 30.

29 corresponds to the XY perspective cross-sectional shape in FIG. 22 and FIG.
FIG. 31 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIGS. 3 to 28 and 30.

30 corresponds to the XY perspective cross-sectional shape in FIG.
FIG. 30 is a schematic cross-sectional view for explaining the liquid discharging operation of the liquid discharging head with time along with FIGS.

FIG. 31 is a schematic perspective view of an ink jet recording apparatus 600 which is an example of a liquid ejection apparatus to which the liquid ejection head of the present invention can be mounted and applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 13 Head 14 Ink groove 15 Heating head 16 Protective film 17-1, 17-2 Electrode 18 Heating resistor layer 19 Heat storage layer 20 Substrate 21 Ink 22 Discharge orifice (micro hole) 23 Meniscus 24 Ink droplet 25 Recording material 26 Multi Groove 27 Glass plate 28 Heating head 40 Ink bag 42 Plug 44 Ink absorber 45 Ink cartridge 51 Paper feed unit 52 Paper feed roller 53 Discharge roller 61 Blade 62 Cap 63 Ink absorber 64 Discharge recovery unit 65 Recording head 66 Carriage 67 Guide Shaft 68 Motor 69 Belt 70 Recording unit 71 Head unit 72 Atmospheric communication port 80 Ink flow path 81 Orifice plate 82 Vibrating plate 83 Piezoelectric element 84 Substrate 85 Discharge port 91 Liquid composition 92 Ink 600 Ink jet recording apparatus 60 1 Inkjet cartridge 602 Drive motor 603, 604 Driving force transmission gear 605 Lead screw 606 Spiral groove 607 Carriage 607a Lever 608 Guide 609 Platen roller 610 Paper press plate 611, 612 Photocoupler 613 Support member 614 Cap member 615 Ink suction means Inner opening 617 Cleaning blade 618 Moving member 619 Main body support 620 (Suction start) lever 621 Cam 832 Discharge port 832a Initiation part 832b Depression part 901 Recording head 931 Electrothermal conversion element (heater, ink discharge energy generation element) 933 Ink supply Port (opening) 934 Substrate 935 Orifice plate (discharge port plate) 935a Discharge port surface 936 Ink channel wall 936a Partition wall 940 Discharge port 1001 Cartridge 1003 Liquid composition storage unit 1005 Ink storage unit 1101 Recording head 1201, 1203 cartridge 1205 Recording head 1301 Recording unit 1303 Recording head 1401 Carriage 1501 Recording head 1337 Bubble chamber 1338 Liquid channel 1141 Groove 1141a Top 100 Inkjet recording head 101 Bubbles 102 Meniscus 1002 Liquid tank 1006 Moving drive unit 1008 Casing 1010 Recording unit 1010a Carriage member 1012 Cartridge 1012Y, M, C, B Inkjet cartridge 1016 Belt 1018 Motor 1020 Drive unit 1022a, 1022b Roller unit 1024a, 1024b Roller unit 1026 1026a, 1 26b pulley 1028 sheet 1030 conveying apparatus 2701 carbon black 2703 water molecules 2705 counterion 2707 potassium ions 2709 sodium ion C wet ink F _M meniscus retraction direction F _C meniscus retraction direction opposite direction G the center of gravity I ink Ia main droplet (liquid, ink ) Ib, Ic liquid (ink adhered to the ink) Id groove (a groove of the ink) Ie liquid flow path ink L liquid chamber remaining in the (ink supply port) of the line N ₁ foaming chamber toward the discharge port from Width N ₂ Length of foaming chamber O Center of discharge port P 'Recording material P Paper transport direction R Belt rotation direction S Direction substantially perpendicular to paper transport direction T ₁ Discharge port recessed part size w Partition wall Width dimension

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) B41J 3/04 102Z

Claims (33)

[Claims] 1. A liquid composition used for forming an ink jet image together with an ink containing a coloring material dispersed in an aqueous medium by the action of an ionic group, comprising (M1) ₂ SO ₄ , CH ₃ COO (M1), Ph-C
OO (M1), (M1) NO ₃ , (M1) Cl, (M
1) Br, (M1) I, (M1) ₂ SO ₃ and (M1)
A liquid composition comprising at least one salt selected from ₂ CO ₃ (where M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group). 2. The method according to claim 1, wherein the salt is used in an amount of 0.05 to 100% based on the total weight of the ink.
The liquid composition according to claim 1, comprising 50 wt%. 3. The method according to claim 1, wherein the salt is added in an amount of 0.1 to 0.1% based on the total weight of the ink.
The liquid composition according to claim 2, comprising 50 wt%. 4. The liquid composition according to claim 1, wherein the liquid composition is discharged by an inkjet method. 5. A composition comprising an aqueous medium and an ink containing a coloring material dispersed in the aqueous medium by the action of an ionic group, and a liquid composition according to claim 1. Characteristic ink set. 6. The ink set according to claim 5, wherein the coloring material is carbon black. 7. The ink set according to claim 5, wherein the coloring material is carbon black, and the carbon black is dispersed by the dispersant having the ionic group. 8. The color material is carbon black,
The ink set according to claim 5, wherein the ionic group is bonded to the surface of the carbon black. 9. The ink set according to claim 5, wherein the coloring material is an organic pigment, and the organic pigment is dispersed by the dispersant having the ionic group. 10. The ink set according to claim 5, wherein the coloring material is an organic pigment, and the ionic group is bonded to a surface of the organic pigment. 11. The ink set according to claim 5, wherein the coloring material is a disperse dye, and the disperse dye is dispersed by the dispersant having an ionic group. 12. The ink set according to claim 5, wherein the coloring material is colored fine particles, and the colored fine particles are dispersed by the ionic group-containing dispersant. 13. The ink set according to claim 5, wherein the ionic group is an anionic group. 14. The ink set according to claim 5, wherein said ink is an ink showing one color tone selected from yellow, magenta, cyan, red, green, blue and black. 15. The ink set according to claim 5, wherein the ink is a combination of two or more inks having different color tones. 16. The method according to claim 16, wherein the two or more inks having different color tones are a yellow ink, a magenta ink, a cyan ink,
The ink set according to claim 15, wherein the ink set is at least two selected from red ink, green, blue, and black inks. 17. The ink set according to claim 5, further comprising a second ink containing an aqueous medium and a dye. 18. The ink according to claim 18, wherein the second ink is at least one selected from inks exhibiting yellow, magenta, cyan, red, green, blue and black tones. 18. The ink set according to claim 17, wherein the ink set has a color tone different from the color tone of the ink containing the color material dispersed by the action of the base. 19. (i) applying an ink containing a water-based medium and a coloring material dispersed in the water-based medium by the action of an ionic group to a recording medium; and (ii) (M1)
₂ SO ₄ , CH ₃ COO (M1), Ph-COO (M
1), (M1) NO ₃ , (M1) Cl, (M1) Br,
(M1) A liquid composition containing at least one salt selected from I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ (provided that
M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group) at least in a region of the recording medium to which the ink is applied. 20. The recording method according to claim 19, wherein the step (i) is performed using an ink jet device. 21. The recording method according to claim 19, wherein the step (ii) is performed using an ink jet device. 22. The recording method according to claim 19, wherein the step (i) is performed after the step (ii). 23. The recording method according to claim 19, wherein the steps (ii), (i) and (ii) are performed in this order. 24. A recording medium containing images of different tones,
A method for forming a multicolor image in which the images with different tones are adjacent to each other, comprising a step of applying the plurality of inks with different tones to a recording medium to form the multicolor image, At least one of the plurality of inks is a colorant-dispersed ink including an aqueous medium and a colorant dispersed in the aqueous medium by the action of an ionic group, and further includes at least the colorant of the recording medium. The liquid composition according to any one of claims 1 to 4 in a region where the dispersion ink is applied, prior to the application of the color material dispersion ink to a recording medium,
Alternatively, a method for forming a multicolor image, comprising a step of applying the colorant-dispersed ink after applying the ink to a recording medium. 25. A recording unit, comprising: a liquid composition container for storing the liquid composition according to claim 1; and an ink jet head for discharging the liquid composition. 26. A liquid composition container containing the liquid composition according to claim 1, an ink jet head for discharging the liquid composition, an aqueous medium, and an action of an ionic group on the aqueous medium. A recording unit, comprising: an ink container that stores ink containing a color material dispersed by the ink jet head; and an inkjet head that discharges the ink. 27. An ink cartridge which contains the liquid composition according to claim 1 and is detachable from an ink jet head which discharges the liquid composition. 28. A liquid composition container containing the liquid composition according to claim 1, an aqueous medium and a coloring material dispersed in the aqueous medium by the action of an ionic group. And an ink head for independently ejecting each of the liquid composition contained in the liquid composition containing section and the ink contained in the ink containing section. Inkjet device. 29. A first recording unit including a liquid composition storage section storing the liquid composition according to claim 1 and an inkjet head for discharging the liquid composition; and an aqueous medium. A second recording unit provided with an ink containing section containing an ink containing a coloring material dispersed in the aqueous medium by the action of an ionic group, and an ink jet head for discharging the ink. Inkjet device. 30. Promotion of fixing of an aqueous medium and an ink containing a coloring material dispersed in the aqueous medium by the action of an ionic group to the recording medium when the ink is applied to the recording medium using an inkjet apparatus. A method comprising: (M1)
₂ SO ₄ , CH ₃ COO (M1), Ph-COO (M
1), (M1) NO ₃ , (M1) Cl, (M1) Br,
(M1) A liquid composition containing at least one salt selected from I, (M1) ₂ SO ₃ and (M1) ₂ CO ₃ (provided that
M1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group) at least at the site of the recording medium to which the ink is applied. . 31. A method for improving the quality of a multicolor image on a recording medium.
Wherein the multicolor image has at least different tones
A first region and a second region, wherein the first region and the second region
A region is at least partially adjacent to each other.
And the first area contains a first ink having a first color tone.
Applying to the recording medium; and at least on the recording medium
Also applying a liquid composition to a portion to which the first ink is applied.
The second region is provided with a second ink having a second color tone.
Formed by a method having a step of applying to a recording medium
Wherein the first ink comprises an aqueous medium and an aqueous medium.
Including coloring materials dispersed by the action of ionic groups
Wherein the liquid composition is (M1)_TwoSO_Four, CH_ThreeCOO (M
1), Ph-COO (M1), (M1) NO_Three, (M
1) Cl, (M1) Br, (M1) I, (M1)_TwoSO _Three
And (M1)_TwoCO_ThreeAt least one salt selected from
The method for improving the quality of a multicolor image characterized by including
And M1 is an alkali metal, ammonium or organic anion.
And Ph represents a phenyl group). 32. A step in which the second region applies the second ink to the recording medium; and a step in which a liquid composition is applied to at least a portion of the recording medium to which the second ink is applied. Wherein the second ink comprises an aqueous medium and a colorant dispersed in the aqueous medium by the action of an ionic group, and the liquid composition comprises (M1) ₂ SO ₄ , CH ₃ COO (M1), Ph-CO
O (M1), (M1) NO ₃ , (M1) Cl, (M1)
Br, (M1) I, (M1) ₂ SO ₃ and (M1) ₂ C
At least one salt selected from O ₃ (provided that M
32. The method of claim 31, wherein 1 represents an alkali metal, ammonium or organic ammonium, and Ph represents a phenyl group. 33. A method according to claim 31, wherein said second ink comprises an aqueous medium and a dye.