JP2002337442A - Liquid composition, ink set, cartridge, recording unit, image forming method and ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid composition, an ink set and an image forming method, by which a highly fine image having a high printing grade with high speed fixing properties, an enough image density, a high uniformity in a solid image, being bleedless and having a favorable color reproducibility is obtained, and, in addition, a recorded image enabling to perfectly satisfy water resistance is obtained in a color ink jet recording to a plain paper. SOLUTION: The liquid composition includes a cationic substance including a cationic resin-like polymer. The ink set is a combination of the liquid composition and an ink including a coloring matter and an anionic compound. The image forming method has a process (A) for adhering the liquid composition to at least the image forming region of a recording medium and a process (B) for giving the ink at least including the coloring matter and the anionic compound to the recording medium by an ink jet recording system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for reducing a so-called color bleeding (phenomenon) which occurs when a color image is formed on plain paper, and for obtaining a water-resistant image. The present invention relates to a liquid composition, a cartridge, a recording unit, an ink set combining the liquid composition, an image forming method, and an ink jet recording apparatus which are optimally used for image formation using a method.

[0002]

2. Description of the Related Art In an ink jet recording method, recording is performed by flying small ink droplets and attaching the ink to a recording medium such as paper. In particular, JP-B-61-59911, JP-B-61-59912, and JP-B-61
According to an ink jet recording method disclosed in JP-A-59914, in which an electrothermal converter is used as an ejection energy supply unit and droplets are ejected by applying thermal energy to ink to generate bubbles, , A high-density multi-orifice can be easily realized, and a high-resolution and high-quality image can be recorded at a high speed. Problems to be solved when performing ink jet recording on a recording medium, for example, plain paper, include the following. (1) The print quality is good while having good fixability. (2) Sufficient image density is obtained and solid image uniformity is high. In addition, the following problems can be mentioned in addition to the above-mentioned problems, particularly when forming a color image on plain paper. (3) Prevent bleeding. (4) Color reproducibility is good, and a high-definition image can be obtained. (5) Complete water resistance of the recorded image.

However, the ink used in the conventional ink-jet recording method contains water as a main component, and contains a water-soluble high-boiling solvent such as glycol for the purpose of preventing drying and preventing nozzle clogging. It is presumed that when recording on plain paper using such an ink, sufficient fixability could not be obtained, or uneven distribution of fillers and sizing agents on the surface of the recording paper. This causes problems such as generation of uneven images. In particular, when trying to obtain a color image, a plurality of colors of ink are successively superimposed before a certain color ink is fixed on the recording paper. ,
There is a problem that the images are mixed unevenly (hereinafter, this phenomenon is called bleeding) and a satisfactory image cannot be obtained.

On the other hand, as a means for improving the fixing property, Japanese Patent Application Laid-Open No. 55-65269 discloses a method of adding a compound for improving the permeability such as a surfactant to the ink. Japanese Patent Application Laid-Open No. 55-66976 discloses the use of an ink mainly containing a volatile solvent. However, in the former method of adding a surfactant or the like to the ink, although the permeability of the ink to the recording paper is increased and the fixing property and the bleeding of the ink are improved to some extent, the coloring material in the ink is also used for the recording paper. Since it penetrates deeply, problems such as a decrease in image density and saturation occur. In addition, the ink spreads in the horizontal direction, and as a result, problems such as a decrease in edge sharpness and a decrease in resolution also occur. On the other hand, in the latter method using an ink mainly composed of a volatile solvent, in addition to the same disadvantages as in the former case described above, clogging due to evaporation of the solvent in the nozzle portion of the recording head occurs. Easy to do and not preferred.

Further, in order to solve the above-mentioned problem, there has been proposed a method of depositing a liquid for improving an image in advance on a recording medium before ejecting ink. For example, JP-A-63-2999971 discloses an ink containing an anionic dye after adhering a liquid containing an organic compound having two or more cationic groups per molecule onto a recording medium. A method for recording the information is disclosed.
JP-A-64-9279 discloses a method in which an acidic liquid containing succinic acid or the like is deposited on a recording medium, and recording is performed with an ink containing an anionic dye. Further, Japanese Patent Application Laid-Open No. 64-63185 discloses a method in which a liquid for insolubilizing a dye is applied prior to recording of ink.

However, any of the above-mentioned methods is intended to improve the bleeding of an image and the water resistance by precipitating the dye itself, so that the above-described effect of suppressing bleeding between color inks is insufficient. Since the dyes are likely to be unevenly distributed on the recording paper, the coverage of the recording paper with pulp fibers is poor, and the uniformity of the image is reduced.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a liquid composition which can be used to achieve the above-mentioned various problems in ink jet recording at a higher level. Another object of the present invention is to provide an inkjet recording apparatus capable of forming a high-quality inkjet recorded matter, a cartridge that can be used therein, and a recording unit. Still another object of the present invention is to provide an image forming method capable of obtaining a high-quality ink jet recorded matter.

[0008]

The above object is achieved by the present invention described below. That is, the liquid composition according to the present invention is a liquid composition containing at least a cationic substance, wherein the cationic substance contains a cationic dendritic polymer. Further, an ink set according to the present invention is characterized in that the above liquid composition is combined with an ink containing at least a coloring material and an anionic compound. Further, a cartridge according to the present invention is provided with a liquid composition storage section that stores the above liquid composition.
According to another aspect of the invention, a recording unit includes: a liquid composition storage unit that stores the liquid composition described above; and a recording head that discharges the liquid composition stored in the liquid composition storage unit. It is characterized by having. Further, in the image forming method according to the present invention, the step (A) of attaching the liquid composition to at least an image forming area of a recording medium.
And a step (B) of applying an ink containing at least a coloring material and an anionic compound to a recording medium by an ink jet recording method. Further, an ink jet recording apparatus according to the present invention includes a liquid composition storage section containing the above liquid composition, an ink storage section containing an ink containing a coloring material and an anionic compound, A recording head for discharging each of the composition and the ink.

[0009]

Next, the present invention will be described in more detail with reference to preferred embodiments. First, along with FIG.
The role of the liquid composition when the liquid composition containing a cationic substance containing a cationic dendritic polymer of the present invention as a main component is used for image formation will be described. Incidentally, for simplicity of description, a case where recording is performed using a dye ink containing a water-soluble dye containing an anionic group as an anionic compound together with the liquid composition of the present invention will be described. The same applies to the case where recording is performed using a pigment ink containing a pigment.

When the liquid composition according to the present invention is used together with an ink containing an anionic compound, for example, an anionic water-soluble dye as a coloring material, the liquid composition is used on the recording paper or at a position where the ink permeates the recording paper. When mixed, as shown in FIG. 9 (c), as a first stage of the reaction, the low molecular weight component of the cationic substance contained in the liquid composition and the anionic compound in the ink Are associated by ionic interaction, and the dye in the ink is instantaneously aggregated and separated from the solution phase.

Next, as a second stage of the reaction, an aggregate of the above anionic compound and a low molecular weight cationic substance is formed.
Since it is adsorbed by the cationic dendritic polymer contained in the liquid composition (preferably having an average particle size of not more than 5.0 μm), the size of the aggregate of the dye formed in the above-mentioned association is further increased. (FIG. 9D), it is difficult to enter the gaps between the fibers of the recording paper. As a result, solid-liquid separation
Since only the liquid portion will seep into the recording paper (FIG. 9)
(E) illustrated), it is possible to achieve both improvement in print quality and improvement in fixability.

At the same time, the viscosity of the aggregate formed by the low molecular weight component of the cationic substance, the anionic dye and the cationic dendritic polymer formed by the mechanism as described above increases, and the movement of the liquid medium increases. Does not move together with the above, even if adjacent dots are formed of different colors of ink as in the above-described conventional full-color image formation, they do not mix with each other and bleeding does not occur. In addition, since the agglomerates are essentially insoluble in water, the formed images have perfect water resistance.
Further, it also has the effect of improving the light fastness of an image formed by the shielding effect of the cationic dendritic polymer.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. First, a liquid composition containing a cationic substance will be described. The liquid composition of the present invention comprises
It is characterized by having a cationic substance containing at least a cationic dendritic polymer. Preferably, the cationic substance has a molecular weight of 1,000 or less and a cationic substance having an average particle diameter of 5.0 μm or less. And a dendritic polymer. More preferably, an embodiment in which a cationic polymer having a molecular weight of 2,000 or more is contained in addition to the above.

The ink set of the present invention is characterized in that the liquid composition of the present invention configured as described above is combined with a recording ink containing at least an anionic compound. At this time, the colored ink for recording used in combination with the liquid composition is an ink containing at least a dye containing an anionic group, or an ink containing at least an anionic compound and a pigment. It is preferable to use

The function and effect of the liquid composition of the present invention are as described above. When used in image formation, first, the cationic substance contained in the liquid composition and the ink having the above-described structure are used. An anionic compound used together with a water-soluble dye having an anionic group or a pigment contained therein forms an aggregate by ionic interaction.
In addition, the formation reaction rate of this aggregate must be extremely high. Next, as the second stage of the reaction, the aggregate is adsorbed by the cationic dendritic polymer contained in the liquid composition.

Hereinafter, the cationic dendritic polymer which is an essential component of the liquid composition of the present invention will be described. As described above, the action and effect of the cationic dendritic polymer in the present invention are as follows. In the second step of the reaction between the liquid composition and the ink, the dye having an anionic group obtained in the first step and the low molecular cation By adsorbing the aggregates composed of the reactive substances into the molecules, the size of the aggregates of the dyes generated by the association is further increased to make it difficult for the dyes to enter the gaps between the fibers of the recording paper. Is left on the recording paper, and only the liquid portion that has been solid-liquid separated penetrates into the recording paper. As a result, both improvement in print quality and improvement in fixability can be achieved.

The cationic dendritic polymer having the above-mentioned effects is one of new polymer materials also called dendritic polymers or hyperbranched polymers, and includes star polymers, dendrimers, ring polymers and the like. This corresponds to this. Dendritic macromolecules are different from conventional polymer materials, in which monomers are linked linearly to form a single chain molecule, and are branched condensates that have a structure that branches off like a tree branch. Is a polymer compound having a generally spherical shape. The dendritic polymer expands into a hard sphere,
Since it has the property that the molecular size and the functional group on the surface can be easily processed, various applications have been considered. The dendritic polymer that can be used in the present invention is a cationic dendritic polymer in which a cationic functional group such as a quaternary ammonium having a positive charge is introduced into a compound having the above characteristics. Such a dendritic polymer, unlike a conventional polymer compound, has the property of relatively hardly increasing the viscosity of a liquid, and is excellent in ink ejection properties. Most suitable for image forming method.

Next, a method for synthesizing the above-mentioned cationic dendritic polymer used in the present invention will be described. As a method for synthesizing the cationic dendritic polymer, a conventionally known method can be applied. For example, Divergen is used.
It can be synthesized by the t method, the Convergent method, or the like. In the Divergent method, a polyfunctional core material serving as a nucleus and a building block for forming a branch are prepared, and the building block is connected from the core material to the outside, and the synthesis is performed by connecting the building blocks. it can. In the Convergent method, the building block in which some reactive groups are masked is connected from the outside, and the dendritic polymer can be synthesized by repeating this operation, contrary to the above-described Divergent method. is there.

Specific examples include those having the following structures. Ammonia is prepared as a core material, and methyl acrylate is added to Michael to synthesize a β-alanine ester. Next, the ester is aminated at the terminal with ethylenediamine to synthesize a compound having three amino groups at the terminal. Further, when the terminal amino group is reacted with methyl acrylate and aminated with ethylenediamine, a dendritic polymer having six amino groups at the terminal is synthesized. By repeating this reaction several times,
A cationic dendritic polymer having an amino group at the terminal can be obtained.

In order to further improve the effects of the present invention,
In the liquid composition of the present invention, in addition to the above-mentioned cationic dendritic polymer, a cationic polymer having a molecular weight of 2,000 or more can be used in combination. Examples of the cationic polymer that can be used at this time include, for example,
Polyallylamine hydrochloride, polyamine sulfone hydrochloride,
Examples include polyvinylamine hydrochloride and chitosan acetate, but of course, the present invention is not limited to these. Further, the present invention is not limited to the above-mentioned hydrochloride type, acetate type and the like. Further, a cationic surfactant, an inorganic metal salt such as a calcium salt or a magnesium salt may be used in combination.

In the present invention, as the cationic polymer, a compound obtained by partially cationizing a nonionic polymer may be used. Specific examples of such a material include a copolymer of vinylpyrrolidone and an aminoalkyl acrylate quaternary salt, and a copolymer of acrylamide and an aminomethylacrylamide quaternary salt. Of course, the invention is not limited to these compounds. The molecular weight described in the present invention means a weight average molecular weight in terms of polyethylene oxide determined by GPC, unless otherwise specified.

The amount of the components contained in the liquid composition of the present invention is not particularly limited, but the content of the cationic dendritic polymer that characterizes the present invention is 0.01 to 0.01 on a weight basis.
It is preferred to be 30% by weight.

Next, other components constituting the liquid composition of the present invention will be specifically described. The liquid composition of the present invention is, in addition to the above-mentioned cationic dendritic polymer and, if necessary, a cationic polymer used in combination therewith, usually,
Consists of water, water-soluble organic solvents and other additives. Examples of the water-soluble organic solvent that can be used in the present invention include dimethylformamide, amides such as dimethylacetamide, ketones such as acetone, ethers such as tetrahydrofuran and dioxane, polyethylene glycol, polyalkylene glycols such as polypropylene glycol, Ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1, 2, 6
Alkylene glycols such as hexanetriol, thiodiglycol, hexylene glycol and diethylene glycol, lower alkyl ethers of polyhydric alcohols such as ethylene glycol methyl ether, diethylene glycol monomethyl ether and triethylene glycol monomethyl ether, ethanol, isopropyl alcohol, n -In addition to monohydric alcohols such as butyl alcohol and isobutyl alcohol, glycerin, N-methyl-2-
Pyrrolidone, 1,3-dimethyl-imidazolidinone, triethanolamine, sulfolane, dimethyl sulfoxide and the like. The content of the water-soluble organic solvent in the liquid composition of the present invention is not particularly limited, but is preferably 5 to 60% by weight, more preferably 5 to 40% by weight based on the total weight of the liquid composition. is there.

The liquid composition of the present invention may further contain, if necessary, a viscosity adjuster, a pH adjuster, a preservative,
Additives such as various surfactants, antioxidants and evaporation promoters may be appropriately blended. The selection of the surfactant is particularly important in adjusting the permeability of the liquid composition into the recording medium.

The liquid composition of the present invention is more preferably colorless, but may be a light-colored liquid that does not change the color tone of each color ink when mixed with the ink on a recording medium. Further, as a preferable range of various physical properties of the liquid composition of the present invention as described above, the pH around 25 ° C. is 3 to 1
2, preferably 3 to 8, more preferably 3 to 5,
The surface tension is 10 to 60 dyn / cm, more preferably 10 to 40 dyn / cm, and the viscosity is 1 to 3 dyn / cm.
0 cps. Is preferably adjusted to be within the range described above. As will be described later, the surface tension of the liquid composition of the present invention is preferably lower than the surface tension of the ink used with the liquid composition.

Next, the ink set of the present invention will be described. In the ink set of the present invention, the liquid composition of the present invention having the above structure is combined with an ink containing at least a coloring material and an anionic compound. The ink that can be used at that time will be described. The ink used in the present invention uses an anionic water-soluble dye containing an anionic group as a coloring material,
Alternatively, when a pigment is used as a coloring material, it is preferable to use an ink obtained by using an anionic compound in combination with the pigment. The ink used in the present invention as described above further includes water, a water-soluble organic solvent and other components, for example,
If necessary, a viscosity adjusting agent, a pH adjusting agent, a preservative, a surfactant, an antioxidant and the like may be contained.

The water-soluble dye having an anionic group which can be used in the present invention includes a color index (Colo Index).
r INDEX), a water-soluble acid dye,
There is no particular limitation as long as it is a direct dye or a reactive dye. In addition, there is no limitation to those not described in the color index as long as they have an anionic group such as a sulfone group and a carboxyl group. The water-soluble dyes mentioned here naturally include those having a pH dependence of solubility.

As the water-soluble organic solvent used in the ink containing the water-soluble dye as described above as a coloring material, the same water-soluble organic solvent used in the liquid composition of the present invention may be used in the same manner. Can be. The same applies to the preferable range of the content of these water-soluble organic solvents in the ink. Further, the preferable physical property range of the ink is exactly the same as that of the liquid composition. However, regarding the surface tension of the ink, it is sometimes more effective to carry out the image forming method of the present invention when the surface tension of the ink is higher than the surface tension of the liquid composition of the present invention.
preferable. Although the details of the reason are not clear, this is because if the surface tension of both is adjusted in this way, for example, in the printing process, the liquid composition that has been ejected first can be used on the recording medium of the ink that is ejected later. It is thought that it is to exhibit the effect that can make the wettability in a uniform.

When a pigment is used as a coloring material of the ink used in the present invention, the amount of the pigment is 1 to 20% by weight, preferably 2 to 12% by weight, based on the total weight of the ink. Use in the range. As the pigment used in the present invention, specifically, those used for black ink include carbon black, for example, furnace method, carbon black produced by a channel method, and primary particles Diameter is 15 to 40 mμ (nm), specific surface area by BET method is 50 to 300 m ² / g, DBP oil absorption is 40 to 150 ml / 100 g, volatile matter is 0.5 to 10
%, And those having characteristics such as a pH value of 2 to 9 are preferably used. As a commercially available product having such characteristics, for example, 2300, no. 900, MCF88, N
o. 33, no. 40, no. 45, no. 52, MA
7, MA8, No. 2200B (Mitsubishi Chemical)
Raven 1255 (all made in Colombia), REGA
L400R, REGAL330R, REGAL660
R, MOGUL L (all made by Cabot), Color
Black FW, COLOR Black FW
18, Color Black S170, Color
Black S150, Printex 35, Pr
index U (all manufactured by Degussa) and the like, and any of them can be preferably used.

Examples of the pigment usable in the yellow ink include C.I. I. Pigment Yellow
w1, C.I. I. Pigment Yellow 2,
C. I. Pigment Yellow 3, C.I. I.
Pigment Yellow 13, C.I. I. Pig
ment yellow 16, C.I. I. Pigmen
t Yellow 83 and the like. Examples of the pigment that can be used in the magenta ink include C.I. I. Pig
Ment Red 5, C.I. I. Pigment Re
d 7, C.I. I. Pigment Red 12, C.I.
I. Pigment Red 48 (Ca), C.I. I.
Pigment Red 48 (Mn), C.I. I. Pi
gment Red 57 (Ca), C.I. I. Pigm
entRed 112, C.I. I. Pigment Re
d122 and the like. Examples of the pigment that can be used for cyan ink include C.I. I. Pigment Bl
ue 1, C.I. I. Pigment Blue 2,
C. I. Pigment Blue 3, C.I. I. Pig
Ment Blue 15: 3, C.I. I. Pigmen
t Blue 16, C.I. I. Pigment Blu
e22, C.I. I. Vat Blue 4, C.I. I. V
at Blue 6 and the like. Of course, the present invention
It is not limited to these. In addition to the above, of course, pigments newly produced for the present invention can also be used.

As a dispersant which can be used when a pigment is used, any dispersant may be used as long as it is a water-soluble resin, but a dispersant having a weight average molecular weight in the range of 1,000 to 30,000 is preferable. More preferably, 3,000-
Use in the range of 15,000. Specific examples of such a dispersant include styrene, styrene derivatives, vinylnaphthalene, vinylnaphthalene derivatives, α,
aliphatic alcohol esters of β-ethylenically unsaturated carboxylic acids, such as acrylic acid, acrylic acid derivatives, maleic acid, maleic acid derivatives, itaconic acid, itaconic acid derivatives, fumaric acid, fumaric acid derivatives, vinyl acetate, vinylpyrrolidone, acrylamide And a block copolymer, a random copolymer, and a graft copolymer comprising at least two or more monomers selected from the group consisting of, and derivatives thereof (at least one of which is a hydrophilic polymerizable monomer). Coalescence, or salts thereof. Or rosin,
Natural resins such as shellac and starch can also be preferably used. These resins are soluble in an aqueous solution in which a base is dissolved, and are alkali-soluble resins. The water-soluble resin used as a pigment dispersant is preferably contained in the range of 0.1 to 5% by weight based on the total weight of the ink.

In particular, in the case of an ink containing the pigment as described above, it is preferable that the entire ink is adjusted to be neutral or alkaline. Such a configuration is preferable because the solubility of the water-soluble resin used as a pigment dispersant can be improved, and an ink having more excellent long-term storage properties can be obtained. However, in this case, it may cause corrosion of various members used in the ink jet recording apparatus. Therefore, it is preferable to set the pH range to 7 to 10. Examples of the pH adjuster used in this case include, for example, diethanolamine, various organic amines such as triethanolamine, sodium hydroxide, lithium hydroxide, inorganic alkali agents such as hydroxides of alkali metals such as potassium hydroxide, Organic acids, mineral acids and the like can be mentioned. The water-soluble resin as a pigment and a dispersant as described above is dispersed or dissolved in an aqueous liquid medium.

An aqueous liquid medium suitable for the ink containing the pigment used in the present invention is a mixed solvent of water and a water-soluble organic solvent. The water is not general water containing various ions, but It is preferable to use ion-exchanged water (deionized water).

Examples of the water-soluble organic solvent used by mixing with water include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol and tert-butyl alcohol. Alkyl alcohols having 1 to 4 carbon atoms; amides such as dimethylformamide and dimethylacetamide; ketones or keto alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylenes such as polyethylene glycol and polypropylene glycol Glycols; ethylene glycol, propylene glycol, butylene glycol, triethylene glycol,
1,2,6-hexanetriol, thiodiglycol,
Alkylene glycols having an alkylene group containing 2 to 6 carbon atoms, such as hexylene glycol and diethylene glycol; glycerin; ethylene glycol monomethyl (or ethyl) ether, diethylene glycol methyl (or ethyl) ether, triethylene glycol monomethyl (or ethyl) Lower alkyl ethers of polyhydric alcohols such as ethers; N-methyl-2-pyrrolidone;
2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like. Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether are preferable.

The content of the water-soluble organic solvent in the ink as described above is generally 3 to 50% by weight of the total weight of the ink.
, More preferably in the range of 3 to 40% by weight. The content of water used is in the range of 10 to 90% by weight, preferably 30 to 80% by weight of the total weight of the ink.

The ink containing the pigment which can be used in the present invention includes, in addition to the above-mentioned components, a surfactant, an antifoaming agent, Preservatives and the like can be appropriately added. Further, in addition to the above-mentioned pigment, a water-soluble dye as described above may be appropriately added as a coloring material. Similarly to the above, when using an ink containing a pigment, it is preferable that the surface tension of the ink is larger than the surface tension of the liquid composition of the present invention. It is preferred that the surface tension of the ink be adjusted accordingly.

As a method for preparing an ink containing a pigment as described above, first, a pigment is added to an aqueous medium containing at least water and a water-soluble resin as a dispersant, and the mixture is mixed and stirred. Dispersion is performed using a dispersing means described later, and centrifugation is performed as necessary to obtain a desired dispersion. Next, a sizing agent and appropriately selected additive components as described above are added to the dispersion, followed by stirring to obtain an ink used in the present invention.

When an alkali-soluble resin as described above is used as a dispersing agent, it is necessary to add a base to dissolve the resin. Organic amines such as ethanolamine, diethanolamine, triethanolamine, amine methylpropanol, and ammonia, and inorganic bases such as potassium hydroxide and sodium hydroxide are preferably used.

In the method for producing an ink containing a pigment, it is effective to carry out premixing for 30 minutes or more before stirring and dispersing an aqueous medium containing the pigment. That is, such a premixing operation is preferable because the wettability of the pigment surface can be improved and the adsorption of the dispersant on the pigment surface can be promoted.

The disperser used in the above-mentioned pigment dispersion treatment may be any disperser that is generally used, and examples thereof include a ball mill, a roll mill and a sand mill. Among them, a high-speed sand mill is preferably used. Such things include, for example, supermills, sand grinders, bead mills,
Agitator mill, Glen mill, Dyno mill, Pearl mill, Kobol mill (all are trade names) and the like.

When an ink containing a pigment is used in an ink-jet recording method, a pigment having an optimum particle size distribution is used due to a demand for clogging resistance and the like, but a pigment having a desired particle size distribution is used. The methods for obtaining the following are to reduce the size of the pulverizing media of the disperser, increase the filling rate of the pulverizing media, lengthen the processing time, reduce the discharge speed, filter after centrifugation, centrifugal separator, etc. And methods such as a combination of these methods.

In the present invention, when an ink containing a pigment is used, in addition to the various components described above, the ink may contain an anionic compound such as an anionic surfactant or an anionic polymer. Is preferably added. In particular, when an anionic compound is not used as a dispersant, it is essential to add such an anionic substance. The addition amount at this time is 0.05 to
10% by weight, preferably 0.2 to 5% by weight. or,
It is also a preferred embodiment that the amphoteric surfactant is contained after being adjusted to a pH below its isoelectric point. Examples of the anionic surfactant used at this time include carboxylate type, sulfate type, sulfonate type, and phosphate type, and any of commonly used ones can be preferably used. . Examples of anionic polymers include alkali-soluble resins, specifically, sodium polyacrylate,
Alternatively, a polymer obtained by copolymerizing acrylic acid with a part of a polymer can be used, but is not limited to these.

Next, the image forming method of the present invention will be described. In the image forming method of the present invention, the liquid composition as described above is applied to at least an image forming area (including an image forming area and its vicinity) on a recording medium. (A)
And an ink containing at least a coloring material and an anionic compound (for example, an ink containing a dye containing at least an anionic group, or an ink containing at least an anionic compound and a pigment) is recorded by an inkjet recording method. It is characterized by including a step (B) of applying to a medium. Note that the image forming area in the present invention is an area where ink dots are attached, and the vicinity of the image forming area is 1 to 1 outside the area where the ink dots are attached.
It indicates an area about 5 dots apart.

The image forming method of the present invention may be any method as long as the liquid composition of the present invention and the ink coexist on a recording medium or the like. It does not matter whether or not is added on the recording medium first. Further, when the liquid composition is first adhered to the recording medium, the time from when the liquid composition is adhered to the recording medium until the ink is adhered onto the recording medium is not particularly limited, It is preferable that the ink be deposited on the recording medium substantially simultaneously or within a few seconds.

The recording medium used in the above-described image forming method is not particularly limited, and so-called plain paper such as copy paper and bond paper, which are conventionally used, is preferably used. Of course, a coated paper specially prepared for ink jet recording or a transparent film for OHP is also preferably used. Furthermore, it can be suitably used for general high-quality paper and glossy paper.

As a method of attaching the liquid composition onto the recording medium, for example, a method of attaching the liquid composition to the entire surface of the recording medium by spraying, a roller, or the like can be considered. More preferably, an image forming area to which the ink adheres, or This is performed by an ink jet recording method that can selectively and uniformly apply the liquid composition only to the image forming area and the vicinity of the image forming area. In this case, various ink jet recording methods can be used, but a particularly preferable method is to discharge droplets using bubbles generated by thermal energy.

Next, the recording apparatus used in the present invention will be described. In the present invention, it is preferable to use a method in which a recording signal is applied to the recording ink of the recording head and droplets are ejected by the generated thermal energy. The configuration of the recording head, which is the main part of the apparatus, is shown in FIGS. In addition, FIG.
FIG. 2 is a sectional view of the head 13 along the ink flow path,
FIG. 2 is a sectional view taken along line AB in FIG. 1.

The head 13 includes a glass, ceramic, or plastic plate having a groove 14 through which ink passes, and a heating head 15 having a heating resistor used for thermal recording (a thin film head is shown in the drawing, but is not limited to this. Is not obtained). The heating head 15 includes a protective film 16 made of silicon oxide or the like, aluminum electrodes 17-1 and 17-2, a heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate 20 having good heat dissipation such as alumina. Is made up of

The recording ink 21 reaches the discharge orifice 22 and forms a meniscus 23 by the pressure P. Here, when an electric signal is applied to the aluminum electrodes 17-1 and 17-2, an area indicated by n of the heating head 15 generates heat rapidly, and bubbles are generated in the ink 21 in contact with the area, and the pressure is increased by the pressure. The meniscus 23 protrudes and becomes an ink droplet 24 from the ejection orifice 22.
Fly towards. FIG. 3 shows a schematic view of a recording head in which a number of nozzles shown in FIG. 1 are arranged. The recording head is formed by closely contacting a glass plate 27 having a number of flow paths and a heating head 28 similar to that described with reference to FIG.

FIG. 4 shows an example of an ink jet recording apparatus incorporating the head. In FIG. 4, reference numeral 61 denotes a blade as a wiping member, one end of which is held by a blade holding member to become a fixed end, and has a form of a wrench lever. The blade 61 is arranged at a position adjacent to the recording area of the recording head 65, and in the case of this example,
The recording head 65 is held in a protruding form in the movement path. Reference numeral 62 denotes a cap on the ejection port surface of the recording head 65, which is disposed at a home position adjacent to the blade 61, moves in a direction perpendicular to the moving direction of the recording head 65, and comes into contact with the ink ejection port surface. A structure for performing capping is provided. Further, reference numeral 63 denotes an ink absorber provided adjacent to the blade 61, and is held in a form protruding into the movement path of the recording head 65, similarly to the blade 61.
The blade 61, cap 62, and ink absorber 63
Constitutes an ejection recovery section 64, and the blade 61 and the ink absorber 63 remove moisture, dust, and the like from the ink ejection port surface.

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. Is a carriage for performing the following. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected to a belt 69 driven by a motor 68 (not shown). As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and the adjacent area.

Reference numeral 51 denotes a paper feed unit for inserting a recording material,
Reference numeral 52 denotes a feed roller driven by a motor (not shown). With such a configuration, the recording material is fed to a position facing the discharge port surface of the recording head 65, and is discharged to a discharge unit provided with a discharge roller 53 as recording proceeds.

In the above configuration, when the recording head 65 returns to the home position at the end of recording or the like, the cap 62 of the ejection recovery section 64 is retracted from the moving path of the recording head 65, but the blade 61 protrudes into the moving path. I have. As a result, the ejection port surface of the recording head 65 is wiped.
When capping is performed with the cap 62 in contact with the ejection opening surface of the recording 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 wiping. As a result, the ejection port surface of the recording head 65 is also wiped during this movement. The movement of the print head 65 to the home position is performed not only at the end of printing or at the time of ejection recovery, but also at the home position adjacent to the printing area at a predetermined interval while the printing head 65 moves through the printing area for printing. And the wiping is performed with this movement.

FIG. 5 is a view showing an example of an ink cartridge 45 containing ink supplied to the head via an ink supply member, for example, a tube. Here, reference numeral 40 denotes an ink storage portion that stores the supply ink, for example, an ink bag, and a rubber stopper 42 is provided at the tip thereof.
By inserting a needle (not shown) into the stopper 42, the ink in the ink bag 40 can be supplied to the head.
An ink absorber 44 receives the waste ink. For the ink container, the liquid contact surface with the ink is polyolefin,
Particularly, those formed of polyethylene are preferable.

The ink jet recording apparatus used in the present invention is not limited to the one in which the head and the ink cartridge are separated as described above, and the one in which they are integrated as shown in FIG. 6 is also suitably used. .

In FIG. 6, reference numeral 70 denotes a recording unit, which contains an ink container containing ink, for example, an ink absorber, and a head in which the ink in the ink absorber has a plurality of orifices. The unit 71 is configured to be ejected as ink droplets. As a material of the ink absorber, for example, polyurethane can be used. Reference numeral 72 denotes an atmosphere communication port for communicating the inside of the recording unit with the atmosphere. This recording unit 70 has the configuration shown in FIG.
The recording head is used in place of the recording head shown in FIG. In the recording apparatus used in the present invention, an ink jet recording apparatus that ejects ink droplets by applying thermal energy to ink has been described above as an example, but a piezo-type ink jet recording apparatus using a piezoelectric element may be used. Available as well.

When the recording method of the present invention is carried out, for example, a recording apparatus in which five recording heads shown in FIG. 3 are arranged on a carriage is used. FIG. 7 shows an example. Reference numerals 81, 82, 83, and 84 denote recording heads for ejecting recording inks of yellow, magenta, cyan, and black, respectively. Reference numeral 85 denotes a head for discharging a colorless liquid composition. The head is disposed in the above-described printing apparatus, and discharges printing ink of each color according to a printing signal. Further, the colorless liquid composition is, for example, previously attached to at least the portion where the recording ink of each color adheres to the recording paper prior to the application. FIG. 7 shows an example in which five recording heads are used. However, the present invention is not limited to this. As shown in FIG. 8, a single recording head uses a yellow, magenta, cyan, black, and colorless liquid composition. It is also preferable to carry out the product by dividing the liquid flow path. Of course, the heads may be arranged such that the recording order of the liquid composition and the ink is opposite to the above-described order.

[0059]

Next, the present invention will be described specifically with reference to examples and comparative examples. In the following description, “parts” and “%” are based on weight unless otherwise specified.

Example 1 (Preparation of Liquid Composition A) First, the following components were mixed and dissolved, and then a membrane filter having a pore size of 0.22 μm (trade name: Fluoropore Filter, manufactured by Sumitomo Electric Industries, Ltd.)
, To obtain a liquid composition A whose pH was adjusted to 3.8. [Components of Liquid Composition A] Starburst (PAMAM) Dendrimer, Generation 4 (trade name: manufactured by Aldrich) 5.0 parts Diethylene glycol 10.0 parts Methyl alcohol 5.0 parts Magnesium nitrate 3.0 parts 77.0 parts of ion exchange water

(Preparation of Ink I) Next, the following components were mixed, and a membrane filter having a pore size of 0.22 μm (trade name: Fluoropore Filter, manufactured by Sumitomo Electric Industries, Ltd.)
Each of the yellow, magenta, cyan, and black color inks Y1, M1, C1, and C2 containing an anionic group-containing dye whose pH is adjusted to 7.8 is filtered under pressure.
B1 was obtained. The combination of Y1, M1, C1, and B1 was used as ink I.

[Yellow ink Y1] C.I. I. Direct Yellow 86 2 parts ・ Thiodiglycol 10 parts ・ Acetyleneol EH 0.05 parts ・ Ion exchange water 87.95 parts

[Magenta Ink M1] C.I. I. Acid Red 289 2.5 parts ・ Thiodiglycol 10 parts ・ Acetyleneol EH 0.05 parts ・ Ion exchange water 87.45 parts

[Cyan Ink C1] I. Acid Blue 9 2.5 parts ・ Thiodiglycol 10 parts ・ Acetyleneol EH 0.05 parts ・ Ion exchange water 87.45 parts

[Black Ink B1] C.I. I. Food Black 2 4.0 parts ・ Thiodiglycol 10 parts ・ Acetyleneol EH 0.05 parts ・ Ion-exchanged water 85.95 parts

An ink set according to the present invention was constructed using the liquid composition A and the ink I obtained as described above in combination, and recording was performed on PPC paper (manufactured by Canon). As the ink jet recording apparatus used, a recording apparatus similar to that shown in FIG. 4 was used, and a color image was formed using the five recording heads shown in FIG. At this time, the liquid composition A was first applied, and first adhered onto the recording paper, and then the ink I was adhered. The recording head used here had a recording density of 360 dpi, and the driving conditions were a driving frequency of 5 kHz. In addition, the ejection volume per dot uses a 40 pl head for each of yellow, magenta, and cyan inks and a colorless liquid composition, and 80 dots per dot for black ink.
pl head was used. Incidentally, these recording conditions are the same throughout the examples and comparative examples in which inks containing the dyes described below are used. The environmental conditions during the printing test are unified to 25 ° C./55% RH.

Example 2 Using an ink set in which the liquid composition A used in Example 1 and an ink I using a dye as a coloring material were used, first, the ink I was attached to recording paper, and then the liquid composition was used. Thing A
Was recorded in the same manner as in Example 1 except that the recording was performed later.

Example 3 (Preparation of liquid composition B) In the same manner as in the case of liquid composition A prepared in Example 1, a liquid composition B of the present example comprising the following components was prepared.

An ink set according to the present invention was constructed by combining the liquid composition B obtained above and an ink I using a dye as a coloring material, and under the same conditions as in Example 1,
Recording was performed on C paper (manufactured by Canon). At this time, first,
The liquid composition B was first applied and allowed to adhere onto a recording paper, and thereafter, the ink I was applied to form an image.

Example 4 Using an ink set in which the same liquid composition B and ink I as used in Example 3 were combined, first, ink I was applied first and allowed to adhere to recording paper. Was recorded in the same manner as in Example 3 except that the recording was performed later.

Example 5 As described below, yellow, magenta, cyan, and black inks Y2, M2, C2, and B2 containing a pigment and an anionic compound, respectively, were obtained. This Y2, M
2, C2 and B2 were combined to form ink II, and together with the liquid composition A used in Example 1, an ink set of this example was formed. Using this ink set, recording was performed on PPC paper (manufactured by Canon). In this embodiment,
After the liquid composition A was first applied and deposited on a recording paper, ink II was deposited to perform printing. The recording head used here had a recording density of 360 dpi, and the driving conditions were a driving frequency of 5 kHz. As for the ejection volume per dot, a head of 40 pl was used for each of the yellow, magenta, and cyan inks and the liquid composition A, and a head of 60 pl was used for each dot for the black ink. Note that these recording conditions are the same throughout the examples in which inks containing pigments described below are used. The environmental conditions during the printing test are unified to 25 ° C./55% RH.

[0072]

The above components were mixed and mixed in a water bath at 70
Heat to ° C. to completely dissolve the resin. 10 parts of newly produced carbon black (MCF88, manufactured by Mitsubishi Kasei) and 1 part of isopropyl alcohol were added to this solution,
After premixing for 0 minutes, dispersion treatment was performed under the following conditions. -Disperser: Sand grinder (Igarashi Kikai)-Grinding media: zirconium beads, 1 mm diameter-Filling ratio of grinding media: 50% (volume ratio)-Grinding time: 3 hours Further, centrifugation (12,000 rpm. 20 minutes) to remove coarse particles to obtain a pigment dispersion.

<Preparation of Ink> Using the above dispersion,
Components having the following composition ratios were mixed to prepare an ink containing a pigment, which was designated as black ink B2. -30.0 parts of the above pigment dispersion-10.0 parts of glycerin-5.0 parts of ethylene glycol-5.0 parts of N-methylpyrrolidone-2.0 parts of ethyl alcohol-48.0 parts of ion-exchanged water

[Yellow ink Y2] Black ink B
Carbon black (MCF8
A pigment-containing yellow ink Y2 was prepared in the same manner as in the preparation of the black ink B2, except that Pigment Yellow 74 was used in place of 10 parts of the product (8, manufactured by Mitsubishi Kasei).

[Magenta Ink M2] Black Ink B
Carbon black (MCF8
A pigment-containing magenta ink M2 was prepared in the same manner as in the preparation of the black ink B2, except that Pigment Red 7 was used in place of 10 parts of the product (8, manufactured by Mitsubishi Kasei).

[Cyan ink C2] Black ink B2
Carbon black (MCF88,
Pigment-containing cyan ink C2 was prepared in the same manner as in the preparation of black ink B2, except that Pigment Blue 15 was used instead of 10 parts of the product.

Example 6 Using a combination of the liquid composition A used in Example 1 and the ink II containing the pigment prepared in Example 5 as a coloring material,
Using the ink set of the present example, print recording was performed in the same manner as in Example 1 except that the ink II was first adhered to the recording paper, and then the liquid composition A was subsequently applied.

Example 7 An ink set according to the present invention was constructed using a combination of the liquid composition B used in Example 3 and the ink II prepared using the pigment prepared in Example 5 as a coloring material. Recording was performed on PPC paper (manufactured by Canon) under the same conditions as in Example 3. In the present example, first, the liquid composition B was firstly applied and allowed to adhere to a recording paper, and thereafter, the ink II was applied and printing was performed.

Example 8 An ink set according to the present invention was constructed using the liquid composition B used in Example 3 and the ink II containing the pigment prepared in Example 5 in combination. Recording was performed on PPC paper (manufactured by Canon) under the same conditions as in Example 3. In the present embodiment, first, the ink II was adhered onto the recording paper, and thereafter, the liquid composition B was post-printed to perform print recording.

Comparative Example 1 Printing and evaluation were performed in exactly the same manner as in Example 1 except that the liquid composition A used in Example 1 was not used.

[Evaluation] Table 1 summarizes the image forming conditions in Examples 1 to 8 and Comparative Example 1. Table 1
An image was formed under each of the conditions shown in (1), and the obtained recorded images were evaluated according to the following evaluation methods and evaluation criteria. Table 2 shows the evaluation results obtained in Examples 1 to 8 and Comparative Example 1.

[0083]

1. Image density A solid image is formed using a liquid composition and black ink, and the reflection density after standing for 12 hours is measured using a reflection densitometer Macbeth R.
It was measured with D915 (manufactured by Macbeth). The evaluation criteria are as follows. ：: Reflection density of 1.30 or more ：: Reflection density of 1.25 or more and less than 1.30 Δ: Reflection density of 1.15 or more and less than 1.25 ×: Reflection density of less than 1.15

2. Fixability After using a liquid composition and a yellow ink and a magenta ink to form a red solid image, another blank sheet is superimposed on the recorded image by its own weight, and the transfer of the image recorded on the back side of the paper disappears. The time until the background contamination did not occur was measured on the basis of the time when the recording was completed as time zero, and used as a measure of fixability. The evaluation criteria are as follows. ◎: Fixing property is less than 20 seconds. ：: Fixing property is from 20 seconds to less than 30 seconds. Δ: Fixing property is from 30 seconds to less than 40 seconds.

3. Character quality Black alphanumeric characters were printed using the liquid composition and black ink, and evaluated visually. When the feathering was hardly conspicuous, it was rated as 、. When the feathering was slightly conspicuous but there was no practical problem, it was rated as 以下.

4. Bleeding Canon Color Bubble Jet Printer BJC-8
In the same print mode as 20J print mode E (1 Pass, one-way print), the liquid composition and the solid portions of the yellow, magenta, cyan, and black inks are printed adjacent to each other, and the bleeding at the boundary between the colors is performed. The extent was visually observed.も の indicates that bleeding hardly occurred, ◎ indicates that bleeding occurred slightly, but was at a level causing no substantial problem, and x indicates other levels.

5. After printing solid images and alphanumeric characters of each color ink of yellow, magenta, cyan and black and leaving it for 1 hour,
It was immersed in tap water at a water temperature of 20 ° C. for 10 seconds. Thereafter, the recording medium was taken out of the water, and the filter paper was pressed lightly to remove the water on the surface of the recorded image, air-dried as it was, and visually evaluated for water resistance. Of yellow, magenta, cyan and black,
The ink having the lowest water resistance was evaluated as the water resistance evaluation result. The water resistance evaluation criteria are as follows. A: There is no flow of the recording agent into the margin portion, and almost no background stain is observed. In addition, bleeding of alphanumeric characters hardly occurs. ：: The recording agent bleeds slightly into the margin, and the alphanumeric characters are slightly blurred, but at a level that does not cause any practical problem. X: The recording agent flowed out to the margin part was terrible, and the background stain was remarkable. The bleeding of alphanumeric characters is also terrible. The area where the liquid composition adhered to the recording medium in the above evaluation was the same area as the image forming area of the ink, and the printing duty was 10% for both the liquid composition and the ink.
0%. Further, the printing direction is unidirectional.

Table 2 shows the evaluation results of the images obtained in Examples 1 to 8 and Comparative Example 1 for the above evaluation items. As is clear from Table 2, in the example,
For fixing properties, character quality, image density, bleeding and water resistance, all good images were obtained,
In Comparative Example 1, only an image having a low density and inferior character quality was obtained, and the water resistance of the image was also inferior.

[0090]

Example 9 Using the liquid composition A used in Example 1 and the three colors of yellow, magenta and cyan in the ink I used in Example 1, solid images were recorded at 100% duty. Then, a so-called process black was formed. All printing conditions were the same as in Example 1. At this time, the evaluation results of the image density, the fixing property, the character quality, the water resistance, and the bleeding at the boundary between the process black and other colors were all good, and the effect of the present invention was confirmed.

[0092]

As described above, according to the present invention, in particular, when color ink jet recording is performed on plain paper, high print quality, high print quality and sufficient image density can be obtained while high-speed fixing property is obtained. In addition, the uniformity of solid images is high, and a high-definition image with good color reproducibility can be obtained with a brie dress.
In addition, there are provided a liquid composition, an ink set, and an image forming method using the same, which can provide an excellent ink jet recorded image in which the above excellent image completely satisfies the water resistance.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a head of an ink jet recording apparatus that can be used in the present invention.

FIG. 2 is a cross-sectional view of a head of an ink jet recording apparatus that can be used in the present invention.

FIG. 3 is an external perspective view of a head of an ink jet recording apparatus that can be used in the present invention.

FIG. 4 is a perspective view illustrating an example of an inkjet recording apparatus that can be used in the present invention.

FIG. 5 is a longitudinal sectional view of an ink cartridge that can be used in the present invention.

FIG. 6 is a perspective view illustrating an example of a recording unit that can be used in the present invention.

FIG. 7 is a perspective view showing a recording unit in which a plurality of recording heads used in an embodiment of the present invention are arranged.

FIG. 8 is a perspective view of another recording head used in the present invention.

FIG. 9 is a schematic diagram for explaining the function of the liquid composition when the liquid composition of the present invention is used for image formation.

[Explanation of symbols]

 13: Head 14: Ink groove 15, 28: Heating head 16: Protective film 17: Aluminum electrode 18: Heating resistor layer 19: Heat storage layer 20: Substrate 21: Ink 22: Discharge orifice (fine hole) 23: Meniscus 24: Ink droplets 25: recording paper 26: multi-groove 40: ink bag 42: rubber stopper 44: ink absorber 45: ink cartridge 51: paper feed unit 52: paper feed roller 53: paper discharge roller 61: blade 62: Cap 63: Ink absorber 64: Ejection recovery unit 65: Recording head 66: Carriage 67: Guide shaft 68: Motor 69: Belt 70: Recording unit 71: Head unit 72: Atmospheric communication port

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Makoto Shioya 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2C056 FC01 2H086 BA02 BA05 BA51 BA59 4J039 AD23 BE01 BE02 BE06 EA15 EA16 EA17 EA38 EA42 EA43 EA47 GA24

Claims (13)

[Claims] 1. A liquid composition containing at least a cationic substance, wherein the cationic substance contains a cationic dendritic polymer. 2. The liquid composition according to claim 1, wherein the liquid composition is discharged by an inkjet recording method. 3. The liquid composition according to claim 1, wherein the liquid composition is used for inkjet recording together with an ink containing a coloring material and an anionic compound. 4. An ink set comprising a combination of the liquid composition according to claim 1 and an ink containing at least a coloring material and an anionic compound. 5. The ink set according to claim 4, wherein the ink set is for inkjet recording. 6. A cartridge comprising a liquid composition storage section for storing the liquid composition according to claim 1. 7. The cartridge according to claim 6, further comprising an ink containing section containing an ink containing a coloring material and an anionic compound. 8. A liquid composition storage section that stores the liquid composition according to claim 1, and a recording head that discharges the liquid composition stored in the liquid composition storage section. A recording unit. 9. An ink storage unit containing an ink containing a colorant and an anionic compound, and a recording head for discharging the ink contained in the ink storage unit. Item 10. The recording unit according to Item 8. 10. A step (A) of attaching the liquid composition according to claim 1 to at least an image forming area of a recording medium.
And a step (B) of applying an ink containing at least a coloring material and an anionic compound to a recording medium by an inkjet recording method. 11. The image forming method according to claim 10, wherein the step (A) is performed after the step (B). 12. The image forming method according to claim 10, wherein the step (A) is performed prior to the step (B). 13. A liquid composition accommodating section accommodating the liquid composition according to claim 1, an ink accommodating section accommodating an ink containing a coloring material and an anionic compound, and the liquid composition And a recording head that discharges each of the inks.