JPH0820720A - Liquid composition, ink set, and method for forming image using the same - Google Patents

Abstract

PURPOSE:To obtain a liq. compsn. which enables a good print quality to be attained in ink jet recording on plain paper by incorporating a polyallylamine and either lithium acetate or urea into the compsn. CONSTITUTION:A polyallylamine and either lithium acetate or urea are incorporated into a liq. compsn. contg. a cationic substance. The substance pref. has at least one peak in the mol.wt. range of 1,000 or lower and at least one peak in the mol.wt. range of 1,500-10,000 in a mol.wt. distribution obtd. by GPC. Pref., a component of the cationic substance which has a peak in the mol.wt. range of 1,000 or lower is not a polyallylamine. In ink jet recording on plain paper, the resultant compsn. gives a good print quality while maintaining a good flexibility, can prevent bleeding, and forms a high-precision image with a good color reproducibility.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for obtaining a water-resistant image by reducing bleeding that occurs when forming a color image on plain paper, and is most preferably used for image formation using an ink jet recording system. The present invention relates to a liquid composition, an ink set using the liquid composition, and an image forming method using the ink set.

[0002]

2. Description of the Related Art An ink jet recording method is one in which a droplet of ink is ejected and the ink is adhered to a recording medium such as paper for recording. In particular, Japanese Patent Publication No. 61-59911, Japanese Patent Publication No. 61-59912, and Japanese Patent Publication No. 61-5.
According to the ink jet recording method of the type disclosed in Japanese Patent No. 9914, in which an electrothermal converter is used as the ejection energy supply means and thermal energy is applied to ink to generate bubbles, the droplets are ejected. High-density multi-orifice can be easily realized, and high-resolution and high-quality images can be recorded at high speed.

However, the ink used in the conventional ink jet recording method contains water as a main component and contains a water-soluble high-boiling point solvent such as glycol for the purpose of preventing drying and preventing nozzle clogging. Therefore, it is estimated that when recording on plain paper using such ink, sufficient fixability may not be obtained, or due to uneven distribution of fillers and sizing agents on the recording paper surface. This causes a problem such as the occurrence of a non-uniform image. or,
In particular, when trying to obtain a color image, the inks of a certain color are successively superposed before the ink of a certain color is fixed on the recording paper. There is a problem that they are not uniformly mixed (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 such as a surfactant which enhances the permeability to ink. Further, JP-A-55-66976 discloses the use of an ink mainly composed of a volatile solvent. However, although the former method of adding a surfactant or the like to the ink increases the permeability of the ink into the recording paper and improves the fixability and bleeding of the ink to some extent, the coloring material in the ink is Since it penetrates deeply, inconveniences such as a decrease in image density and saturation occur. In addition, the ink spreads in the horizontal direction, resulting in problems such as a decrease in edge sharpness and a decrease in resolution. On the other hand, in the case of the latter method using an ink mainly composed of a volatile solvent, in addition to the same inconvenience as in the former case, clogging occurs due to evaporation of the solvent in the nozzle portion of the recording head. It was easy to do and was not preferable.

Further, in order to improve the above-mentioned problems, 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, in JP-A-63-29971, an ink containing an anionic dye is prepared by depositing a liquid containing an organic compound having two or more cationic groups per molecule on a recording medium. The method of recording is disclosed in.
Further, 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 then recording is performed with an ink containing an anionic dye. Further, Japanese Patent Application Laid-Open No. 64-63185 discloses a method of applying a liquid insolubilizing a dye prior to ink recording.

However, in any of the above-mentioned methods, since the bleeding and water resistance of the image are improved by precipitating the dye itself, the effect of suppressing bleeding between the color inks described above is insufficient, and the precipitation Since the dyes are likely to be unevenly distributed on the recording paper, the coverage of the recording paper on the pulp fibers is poor and the uniformity of the image is deteriorated.

[0007]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to solve the following five problems in view of the above circumstances. That is, the following two points can be cited as problems in performing inkjet recording on plain paper. Print quality should be good while having good fixability. Sufficient image density is obtained and the solid image uniformity is high. In addition, the following three points are raised as problems especially when forming a color image on plain paper. Prevent bleeding. Good color reproducibility and high-definition images can be obtained. Make the recorded image completely waterproof. Further, an object of the present invention is to improve the long-term storage stability of the liquid composition used for achieving the above object.

[0008]

The above object can be achieved by the present invention described below. That is, the present invention is a liquid composition containing at least a cationic substance, containing at least polyallylamine, and containing either lithium acetate or urea, a liquid composition thereof. An ink set using the composition and an image forming method using the ink set.

[0009]

The function of the liquid composition containing the cationic substance according to the present invention will be described with reference to the drawings. When the liquid composition containing the cationic substance according to the present invention is mixed with the ink containing the anionic compound and mixed with the ink on the recording paper or at the position where the ink penetrates into the recording paper, the liquid composition shown in FIG. As shown, as the first step of the reaction, a low molecular weight component of the cationic substance contained in the liquid composition, for example, a low molecular weight polyallylamine (allylamine oligomer) or a cationic surfactant is used. , The anionic compound in the ink associates with each other by ionic interaction, and instantaneously separates from the solution phase.

Next, in the second step of the reaction, an aggregate of an anionic compound and a low molecular weight cationic substance is adsorbed by a high molecular weight component contained in the liquid composition, and thus the coagulation is generated. The size of the collection is even larger (d),
Difficult to enter the gap between fibers of recording paper. As a result, solid-liquid separation occurs, and only the liquid portion permeates into the recording paper (e), so that both improvement in printing quality and improvement in fixing property can be achieved. At the same time, the viscosity of the aggregate formed by the low molecular weight component of the cationic substance, the anionic compound, and polyallylamine, which is the high molecular weight component of the cationic substance, generated by the mechanism as described above, increases, Since it does not move with the movement of the liquid medium, even when adjacent dots are formed with different color inks like in the case of the conventional full-color image formation described above, they do not mix with each other, and bleeding does not occur. It won't happen. Further, since the above-mentioned aggregate is essentially insoluble in water, the water resistance of the formed image is perfect. Further, it also has the effect of improving the light fastness of the image formed by the polymer shielding effect.

Regarding the action and effect of lithium acetate or urea contained in the liquid composition containing the cationic substance according to the present invention, polyallylamine capable of exhibiting a particularly excellent function as the cationic substance having the above-mentioned function. In the case of using the above-mentioned, by containing and containing either of the components of lithium acetate or urea, the long-term storage stability of the liquid composition containing the polyallylamine is improved.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the preferred embodiments of the present invention. The liquid composition according to the present invention is a liquid composition containing at least a cationic substance, characterized by containing polyallylamine as an essential component, and further containing either component of lithium acetate or urea. . Further, as a liquid composition of a more preferable embodiment, as the cationic substance, the presence region of the peak in the molecular weight distribution of the cationic substance measured by using GPC is at least one in the molecular weight range shown below and It is an embodiment using a certain cationic substance, more preferably an embodiment in which a substance having a peak in the molecular weight distribution of the cationic substance is different from polyallylamine in the molecular weight range shown below. .

A low molecular weight cationic substance having a molecular weight distribution peak measured by GPC in a region having a molecular weight of 1,000 or less, more preferably a molecular weight of 100 to 7
A low molecular weight cationic substance present in the region of 00. A high molecular weight cationic substance in which the peak of the molecular weight distribution measured by GPC is present in a region having a molecular weight of 1,500 or more and 10,000 or less. Incidentally, the molecular weight described in the present invention, unless otherwise specified,
It refers to the weight average molecular weight in terms of polyethylene oxide calculated by GPC.

The ink set according to the present invention is characterized by using the liquid composition according to the present invention as described above, and preferably at least as a colored ink for recording used together with the liquid composition. An ink containing a dye containing an anionic group or an ink containing at least an anionic compound and a pigment is used.

The components of the liquid composition according to the present invention will be described below. The liquid composition according to the present invention needs to contain at least a cationic substance,
It contains polyallylamine, which is one of the cationic substances, as an essential component. The polyallylamine used in this case may have any molecular weight as long as it can achieve the intended purpose of the present invention, and the content thereof is not particularly limited, but is preferably described in the above and It is preferable to use one having at least one peak of the molecular weight distribution in the molecular weight region of. Further, more preferably, a cationic substance different from polyallylamine as a low molecular weight cationic substance having a peak of the molecular weight distribution in the molecular weight range of 1,000 or less as described in, for example,
It is preferable to use a cationic surfactant or the like and use it in combination with polyallylamine.

The operation and effect of the liquid composition according to the present invention are as described above. However, since the liquid composition contains a cationic substance, when the ink is mixed with the recording medium or the like, first of all, , For example, a molecular weight of 100 as indicated above
The low molecular weight cationic substance having a molecular weight distribution peak in the region of 0 or less and the anionic compound contained together with the coloring material in the ink first form an aggregate by an ionic interaction. The formation reaction rate of this aggregate needs to be extremely high.

Here, the above-mentioned molecular weight of 100
A cationic substance having a peak of molecular weight distribution in the region of 0 or less, more preferably a low molecular weight cationic substance having a peak in the region of molecular weight of 100 to 700 will be explained. Specifically, the following substances are mentioned. Used. Specifically, for example, primary, secondary and tertiary amine salt type compounds, specifically, polyallylamine (allylamine oligomer), laurylamine, coconut amine, stearylamine, rosinamine and the like hydrochlorides, acetates and the like; Fourth
Primary ammonium salt type compounds, specifically cetyltrimethylammonium chloride, lauryltrimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltributylammonium chloride, benzalkonium chloride, etc .; pyridinium salt type compounds, specifically cetylpyridinium Chloride,
Cetylpyridinium bromide and the like; imidazoline type cationic compounds, specifically 2-heptadecenyl-hydroxyethyl imidazoline and the like; ethylene oxide adducts of higher alkyl amines, specifically dihydroxyethyl stearyl amine and the like are preferable.

Further, in the present invention, other p
Amphoteric surfactants that exhibit a cationic property in the H region are also preferably used as the low molecular weight cationic substance.
Specifically, for example, an amino acid type amphoteric surfactant; RN
H-CH ₂ -CH ₂ -COOH type compounds; betaine type compounds, specifically, stearyl dimethyl betaine, other carboxylic acid salt type amphoteric surfactants such as lauryl betaine, sulfuric ester type, sulfonic acid Mold,
Examples include amphoteric surfactants such as phosphoric acid ester type. Of course, when these amphoteric surfactants are used, the liquid composition according to the present invention is adjusted so as to have a pH below their isoelectric point, or this liquid composition is mixed with ink on the recording medium. In this case, it is necessary to adjust the pH so that the pH is below the isoelectric point. Although examples of low molecular weight cationic substances have been given above as the cationic substances, it goes without saying that the cationic substances that can be used in the present invention are not necessarily limited to these.

Next, the action and effect of the high molecular weight cationic substance having the peak of the above-mentioned molecular weight distribution in the region of 1,500 or more and 10,000 or less, for example, high molecular weight polyallylamine, in the present invention will be described. As also mentioned above, as a second step of the reaction between the liquid composition and the ink, an association product with a low molecular weight component of a cationic substance as shown in the above-mentioned dye having an anionic group is incorporated into the molecule. Printing is performed by making the size of the aggregate of dyes generated by association further increase and making it difficult for the dye to enter the gaps between the fibers of the recording paper so that only the liquid part that is solid-liquid separated penetrates into the recording paper. It is about achieving both quality and fixability. Examples of the polyallylamine used in the present invention having the above-mentioned action and effects include, but are not limited to, a hydrochloride salt type and an acetate salt type.

The amount of the above-mentioned cationic substance contained in the liquid composition according to the present invention is preferably 0.05 to 20% by weight on a weight basis, more preferably 0.5. Although it is in the range of 10% by weight, it is necessary to determine the optimum range depending on the combination of substances used. Further, the content of the water-soluble surfactant agent is 0.
It is preferably in the range of 05 to 10% by weight.

The content of lithium acetate or urea in the liquid composition, which is another essential component of the liquid composition according to the present invention, in combination with the above-mentioned polyallylamine, is:
It is not particularly limited as long as it is a range that can achieve the intended purpose of the present invention of improving the long-term storage stability of a liquid composition containing a polyallylamine, in the liquid composition,
It is preferable to contain about 0.1 to 20% by weight. If it is less than 0.1% by weight in the liquid composition, the intended purpose cannot be achieved, while if it is more than 20% by weight, the viscosity of the liquid composition may increase, which is not preferable.

Next, other components constituting the liquid composition according to the present invention will be specifically described. The colorless or light-colored liquid composition according to the present invention generally comprises water, a water-soluble organic solvent, and other appropriate additives in addition to the above-mentioned polyallylamine and lithium acetate or urea. Examples of the water-soluble organic solvent used at this time include amides such as dimethylformamide and dimethylacetamide, ketones such as acetone, ethers such as tetrahydrofuran and dioxane, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, and ethylene. Glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol,
Alkylene glycols such as diethylene glycol, lower alkyl ethers of polyhydric alcohols such as ethylene glycol methyl ether, diethylene glycol monomethyl ether and triethylene glycol monomethyl ether, monohydric alcohols such as ethanol, isopropyl alcohol, n-butyl alcohol and isobutyl alcohol. , Glycerin, N-methyl-2-pyrrolidone,
1,3-Dimethyl-imidazolidinone, triethanolamine, sulfolane, dimethylsulfoxide and the like are preferably used. The content of the water-soluble organic solvent 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.

In addition to the above, the liquid composition according to the present invention may further contain a viscosity adjusting agent, a pH adjusting agent, an antiseptic agent, if necessary.
Additives such as various surfactants, antioxidants, and evaporation promoters may be appropriately mixed. The selection of the surfactant is particularly important in adjusting the permeability of the liquid into the recording medium. The liquid composition according to the present invention is more preferably colorless, but when mixed with ink on a recording medium,
It may be a light-colored ink that does not change the color tone of each color ink. Further, as a suitable range of various physical properties of the liquid composition as described above, at about 25 ° C., the pH is 3 to 12, preferably 3 to 8, more preferably 3 to 5, and the surface tension is 10.
-60 dyn / cm, more preferably 10-40 dyn
/ Cm and the viscosity is 1 to 30 cps. It is what As will be described later, the surface tension of the liquid composition according to the present invention is preferably lower than the surface tension of the ink used with the liquid composition.

Regarding the molecular weight distribution of the cationic compound used in the present invention, GPC measurement may be carried out individually in advance, or after measuring the molecular weight distribution of the liquid composition itself, it has at least an anionic group. A sufficient amount of ink containing a dye and the liquid composition were mixed and stirred in a beaker, and after removing the precipitate, GPC measurement was performed again. Before mixing the ink and after mixing the ink and removing the precipitate, It may be obtained by comparing the measurement results of GPC and from the molecular weight distribution of the components that are precipitated by the dye in the ink and removed from the system.

Next, the ink constituting the ink set according to the present invention will be described. For the ink used in the present invention, a water-soluble dye containing an anionic group is used as a coloring material, or when a pigment is used as a coloring material, a combination of an anionic compound is used. In addition to the above-mentioned ink used in the present invention, water, a water-soluble organic solvent and other components such as a viscosity modifier, pH
A regulator, an antiseptic, a surfactant, an antioxidant and the like are contained as necessary.

The water-soluble dye containing an anionic group used in the present invention includes a color index (COLO).
There is no particular limitation as long as it is a water-soluble acid dye, direct dye or reactive dye described in UR INDEX).
Further, even those not described in the color index are not particularly limited as long as they have an anionic group such as a sulfone group and a carboxyl group. Of course, the water-soluble dyes referred to herein include those whose solubility is pH-dependent.

As the water-soluble organic solvent contained in the ink containing the water-soluble dye as the coloring material as described above,
The water-soluble organic solvent used in the liquid composition according to the present invention, which is colorless or light-colored as described above, can be similarly used.
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 preferable that the surface tension of the ink is higher than the surface tension of the liquid composition according to the present invention, because it may be effective in carrying out the image forming method according to the present invention. This is because if the surface tensions of the two are adjusted in this manner, for example, in the printing process, the liquid composition ejected first can have an even wettability of the ink ejected later on the recording medium. It is thought that it will be exerted, but the details are not clear.

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. Used in the range. Specific examples of the pigment used in the present invention include carbon black used as a black ink. For example, carbon black produced by a furnace method or a channel method may be used. Diameter is 15 to 40 mμ, specific surface area by BET method is 50 to 300 m ² / g, DBP oil absorption is 40 to 1
Those having characteristics such as 50 ml / 100 g, volatile content of 0.5 to 10%, and pH value of 2 to 9 are preferably used.
Examples of commercially available products having such characteristics include No.
2300, No. 900, MCF88, No. 33, N
o. 40, No. 45, No. 52, MA7, MA8,
No. 2200B (Made by Mitsubishi Kasei), RAVEN12
55 (Made in Colombia), REGAL400R, RE
GAL330R, REGAL660R, MOGUL L
(Above made by Cabot), Color Black FW
1, COLOR Black FW18, Color
Black S170, Color Black S1
50, Printex 35, Printex U (all manufactured by Degussa) and the like, and any of them can be preferably used.

As the pigment used for the yellow ink, for example, C.I. I. Pigment Yellow
w 1, 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
Examples of pigments used in 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 used for the 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
e 22, C.I. I. Vat Blue 4, C.I. I. V
Examples thereof include at Blue 6 and the like, but the present invention is not limited thereto. In addition to the above, it is of course possible to use pigments newly produced for the present invention.

As the dispersant to be contained in the ink when a pigment is used, any water-soluble resin can be used, but the weight average molecular weight is 1,00.
The range of 0 to 30,000 is preferable, and the range of 3,000 to 15,000 is more preferably used. Specific examples of such a dispersant include styrene, styrene derivatives, vinylnaphthalene, vinylnaphthalene derivatives, α, β-ethylenically unsaturated carboxylic acid aliphatic alcohol esters, acrylic acid, acrylic acid derivatives, and maleic acid. , Maleic acid derivative, itaconic acid, itaconic acid derivative, fumaric acid, fumaric acid derivative, vinyl acetate, vinylpyrrolidone, acrylamide,
And a block copolymer composed of at least two or more monomers (at least one of which is a hydrophilic monomer) selected from derivatives thereof, a random copolymer, a graft copolymer, or a copolymer thereof. Salt etc. are mentioned. Alternatively,
Natural resins such as rosin, shellac and starch can also be preferably used. These resins are alkali-soluble resins that are soluble in an aqueous solution in which a base is dissolved.
The water-soluble resin used as the pigment dispersant is preferably contained in the range of 0.1 to 5% by weight based on the total weight of the ink.

Particularly, in the case of an ink containing the above-mentioned pigment, it is preferable that the entire ink is adjusted to be neutral or alkaline. This is preferable because the solubility of the water-soluble resin used as the pigment dispersant can be improved and the ink can be further excellent in long-term storage stability. However, in this case, it may cause corrosion of various members used in the inkjet recording apparatus. Therefore, it is preferable that the pH range is 7 to 10. Examples of the pH adjuster used in this case include various organic amines such as diethanolamine and triethanolamine, inorganic alkali agents such as sodium hydroxide, lithium hydroxide, and alkali metal hydroxides such as potassium hydroxide, Examples include organic acids and mineral acids. The water-soluble resin, which is a pigment and a dispersant as described above, is dispersed or dissolved in an aqueous liquid medium.

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

The water-soluble organic solvent used by mixing with water includes, for example, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, etc. 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 in which the alkylene group such as hexylene glycol and diethylene glycol contains 2 to 6 carbon atoms; 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 can be mentioned. 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 as described above in the ink is generally in the range of 3 to 50% by weight, preferably 3 to 40% by weight based on the total weight of the ink.
Also, the content of water used is 1 of the total weight of the ink.
The range is 0 to 90% by weight, preferably 30 to 80% by weight.

Further, the ink containing the pigment used in the present invention contains, in addition to the above-mentioned components, a surfactant, a defoaming agent, and a defoaming agent in order to obtain an ink having desired physical properties, if necessary. Preservatives and the like can be added as appropriate. In addition to the above pigments, water-soluble dyes such as those described above can be added as appropriate as a coloring material. Further, 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 according to the present invention. It is preferable to adjust the surface tension of the ink in such a manner as described above.

As a method for producing an ink containing a pigment as described above, first, the pigment is added to an aqueous medium containing at least a water-soluble resin as a dispersant and water,
After stirring, dispersion is carried out using a dispersion means described later, and if necessary, centrifugal separation is carried out to obtain a desired dispersion liquid. Next, a sizing agent and appropriately selected additive components such as those mentioned above are added to this dispersion, and the mixture is stirred to obtain the ink used in the present invention.

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

Further, in the method of producing an ink containing a pigment, it is effective to carry out premixing for 30 minutes or more before stirring and dispersing the pigment-containing aqueous medium. That is, such premixing operation is preferable because it improves wettability of the pigment surface and promotes adsorption of the dispersant on the pigment surface.

The disperser used in the dispersion treatment of the above-mentioned pigment may be any disperser generally used, and examples thereof include a ball mill, a roll mill and a sand mill. Among them, a high speed type sand mill is preferably used, and as such a thing, for example, a super mill, a sand grinder, a bead mill,
Examples thereof include agitator mill, grain mill, dyno mill, pearl mill and cobol mill (all are trade names).

When an ink containing a pigment is used in an ink jet recording method, a pigment having an optimum particle size distribution is used because of the demand for anti-clogging property and the like, but it has a desired particle size distribution. As a method of obtaining a pigment,
Decrease the size of the crushing media of the disperser, increase the filling rate of the crushing media, lengthen the processing time, slow the discharge speed, classify with a filter or centrifuge after crushing, and these Methods such as a combination of the above methods can be mentioned.

In the present invention, when an ink containing a pigment is used, in addition to the various components described above in the ink, an anionic compound such as an anionic surfactant or an anionic polymer substance is used. Is preferably added. Especially 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 from 0.05 to
It is 10% by weight, preferably 0.2 to 5% by weight.

Further, an amphoteric surfactant is added at a p below its isoelectric point.
It is also a preferred embodiment to adjust the content to H and to contain it. As an example of the anionic surfactant used at this time, generally used ones such as carboxylate type, sulfate type, sulfonate type and phosphate type can be preferably used. . Examples of the anionic polymer include alkali-soluble resins, specifically, sodium polyacrylate, and those obtained by copolymerizing acrylic acid with a part of the polymer. Of course, it is not limited to these.

Next, the image forming method according to the present invention will be described. In the image forming method according to the present invention, the liquid composition as described above is applied to an image forming area on a recording medium, or an image forming area and its vicinity. And (A) in which the ink containing at least an anionic group-containing dye or the ink containing at least an anionic compound and a pigment is ejected as a droplet from an ejection orifice onto a recording medium according to a recording signal. And the step (B) of performing. The image forming area referred to in the present invention is an area to which ink dots are attached, and the vicinity of the image forming area is 1 to 1 outside the area to which ink dots are attached.
It means an area about 5 dots apart.

The image forming method according to the present invention may be any method as long as the above-mentioned liquid composition and ink according to the present invention coexist on a recording medium or the like. Therefore, the liquid composition and ink It does not matter which of the above is applied to the recording medium first. Further, when the liquid composition is first adhered to the recording medium, the time from adhering the liquid composition to the recording medium to adhering the ink onto the recording medium is not particularly limited. It is preferable to deposit the ink on the recording medium at substantially the same time or within a few seconds.

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

As a method of applying the liquid composition onto the recording medium, for example, a method of applying the liquid composition onto the entire surface of the recording medium by a spray, a roller or the like can be considered, but more preferably, an image forming area to which the ink is attached, or It is preferable to carry out by an ink jet method capable of selectively and uniformly adhering the liquid composition only to the image forming area and the vicinity of the image forming area. At this time, various ink jet recording methods can be used, but a particularly preferable method is a method of ejecting droplets by using bubbles generated by thermal energy.

Next, a recording apparatus preferably used in the image forming method according to the present invention will be described. In the present invention, an inkjet recording method is preferably used in which a recording signal is applied to the ink of the recording head and the generated thermal energy ejects droplets. The structure of the recording head, which is the main part of such an apparatus, is shown in FIGS. 1, 2 and 3.

The head 13 has a heating head 15 having a heating resistor used for heat-sensitive recording, such as glass, ceramics, or plastic in which ink is formed as a flow path (the head is shown in the figure, but the present invention is not limited to this. Not a thing)
It is obtained by bonding and. The heating head 15 includes a protective film 16 made of silicon oxide or the like, an aluminum electrode 17-
1, 17-2, heating resistor layer 1 formed of nichrome, etc.
8, a heat storage layer 19, and a substrate 20 having a good heat dissipation property such as alumina. The ink 21 reaches the ejection orifice 22, and the pressure P forms a meniscus 23.

Here, when an electric signal is applied to the electrodes 17-1 and 17-2, the area indicated by n of the heating head 15 rapidly generates heat, and bubbles are generated in the ink 21 in contact therewith, and The meniscus is ejected by the pressure, becomes a recording droplet 24 from the orifice 22, and flies toward the recording material 25. FIG. 3 shows a schematic view of a recording head in which a large number of nozzles shown in FIG. 1 are arranged. The recording head is made by closely adhering a glass plate or the like 27 having a large number of flow paths to a heating head 28 similar to that described in 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 of 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 be a fixed end, which is in the form of a wrench lever. The blade 61 is arranged at a position adjacent to the recording area of the recording head, and is configured to move in a direction perpendicular to the moving direction of the recording head to come into contact with the ejection port surface to perform capping. Further, 63 is an ink absorber provided adjacent to the blade 61, and like the blade 61, is held in a form protruding in the moving path of the recording head. The blade 61, the cap 62, and the absorber 63 constitute an ejection recovery unit 64, and the blade 61 and the absorber 63 remove water, dust, and the like from the ink ejection port surface.

Reference numeral 65 denotes a recording head having ejection energy generating means for ejecting ink onto a recording material facing the ejection port surface where ejection ports are arranged for recording, and 66 a recording head having the recording head 65 mounted thereon. A carriage for moving 65. The carriage 66 is movably engaged with the guide shaft 67, and a part of the carriage 66 is connected (not shown) to a belt 69 driven by a motor 68. As a result, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move the recording area and its adjacent area. Reference numeral 51 is a paper feed section for inserting a recording material, and 52 is a paper feed roller driven by a motor (not shown). With these configurations, the recording material is fed to the position facing the ejection port surface of the recording head,
As the recording progresses, the paper is ejected to the paper ejecting section provided with the paper ejecting roller 53.

In the above structure, when the recording head 65 returns to the home position after recording is completed, the cap 62 of the head recovery section 64 is retracted from the movement path of the recording head 65, but the blade 61 is projected into the movement path. There is. As a result, the ejection port surface of the recording head 65 is wiped. When the cap 62 comes into contact with the ejection port surface of the recording head 65 to perform capping, the cap 62 moves so as to project 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 in the same positions as the above wiping positions. As a result, the ejection opening surface of the recording head 65 is wiped even during this movement. The above-mentioned movement of the recording head to the home position is performed not only at the end of recording and at the time of ejection recovery, but also at a predetermined interval to the home position adjacent to the recording area while the recording head moves in the recording area for recording. However, the wiping is performed along with this movement.

FIG. 5 is a diagram showing an example of an ink cartridge in which ink is supplied to the head via an ink supply member, for example, a tube. Here, 40 is an ink containing portion containing 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 this stopper 42, the ink in the ink bag 40 can be supplied to the head. Four
Reference numeral 4 is an absorber that receives waste ink. As the ink storage portion, it is preferable that the liquid contact surface with the ink is formed of polyolefin, particularly polyethylene. The ink jet recording apparatus used in the present invention is not limited to the above-described head and ink cartridge which are separate bodies, and those in which they are integrated as shown in FIG. 6 are also preferably used.

In FIG. 6, reference numeral 70 denotes a recording unit, in which an ink containing portion containing ink, for example, an ink absorber is contained, and the ink in the ink absorber has a plurality of orifices. It is configured to be ejected as an ink droplet from the portion 71. As a material for 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. The recording unit 70 is used instead of the recording head shown in FIG. 4, and is detachable from the carriage 66. In the recording apparatus used in the present invention, an ink jet recording apparatus that applies thermal energy to ink to eject ink droplets has been described above as an example. However, in addition to this, a piezo type ink jet recording apparatus that uses a piezoelectric element may also be used. You can use it as well.

When the recording method of the present invention is carried out, for example, a recording device in which five recording heads shown in FIG. 3 are arranged on a carriage is used. FIG. 7 shows an example thereof. Reference numerals 81, 82, 83, and 84 are recording heads for ejecting inks of yellow, magenta, cyan, and black colors, respectively. Reference numeral 85 is a head for ejecting the liquid composition. The head is arranged in the above-mentioned recording device and ejects ink of each color according to a recording signal. In addition, prior to that, the liquid composition is applied in advance to at least a portion where each color ink is applied to the recording paper. Although FIG. 7 shows an example in which five recording heads are used, the present invention is not limited to this, and as shown in FIG. 8, one recording head is used for yellow, magenta, cyan, black and colorless liquid compositions. It is also preferable to perform the process in separate liquid flow paths. Of course, the heads may be arranged such that the order of recording the colorless liquid composition and the ink is the reverse of the order described above.

[0057]

EXAMPLES The present invention will be described more specifically by showing Examples and Comparative Examples below. In the text, "part" and "%" are based on weight unless otherwise specified. The peak of the molecular weight distribution of the cationic substance was measured by GPC using polyethylene oxide as a standard. Further, the weight average molecular weight of the dispersant of the pigment ink was measured by the GCP method using styrene polymer as a standard, and the average particle diameter of the dispersant was measured by the dynamic light scattering method.

Example 1 First, the following components were mixed and dissolved, and then pressure-filtered with a membrane filter (trade name: Fluoropore filter, manufactured by Sumitomo Electric Industries) having a pore size of 0.22 μm, and then N
The pH was adjusted to 7.5 with aOH, and colorless liquid composition A of this example was obtained. Regarding polyallylamine, functional materials, Vol. 5,29 (1986). The same applies to the other examples below.

Components of liquid composition A : polyallylamine hydrochloride (peak of molecular weight distribution = 700) 5 parts thiodiglycol 10 parts lithium acetate 0.5 parts water 84.5 parts

(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)
In order to obtain yellow, magenta, cyan, and black color inks Y1, M1, C1, and B1 containing a dye containing an anionic group, pressure filtration was performed. This Y1, M1,
Recording liquid I is C1 and B1.

Yellow ink Y1 · C. I. Direct Yellow 142 2 parts-Thiodiglycol 10 parts-Acetylenol EH (Kawaken Fine Chemicals) 0.05 parts-Water 87.95 parts

Magenta ink M1 · C. I. Acid Red-289 2.5 parts-Thiodiglycol 10 parts-Acetylenol EH (Kawaken Fine Chemicals) 0.05 parts-Water 87.95 parts

Cyan ink C1.C. I. Acid Blue 9 2.5 parts-Thiodiglycol 10 parts-Acetylenol EH (Kawaken Fine Chemicals) 0.05 parts-Water 87.95 parts

Black ink B1 · C. I. Food Black-2 4.0 parts-Thiodiglycol 10 parts-Acetylenol EH (Kawaken Fine Chemicals) 0.05 parts-Water 84.95 parts

An ink set according to the present invention was constructed using the colorless liquid composition A of this example and ink I obtained as described above, and recording was carried out on PPC paper (manufactured by Canon Inc.). The inkjet recording device used is shown in FIG.
A color image was formed using the same recording apparatus as shown in FIG. 5 and using the five recording heads shown in FIG. On this occasion,
The liquid composition A was first ejected and deposited on the recording paper, and then the ink I was deposited. The recording head used here had a recording density of 360 dpi, and the driving condition was a driving frequency of 5 kHz. The ejection volume per dot is 45 pl for yellow, magenta and cyan inks, and the colorless liquid composition is 80 pl per dot for black ink.
I used the head. The recording conditions are the same throughout the examples and comparative examples when the ink containing the dye described below is used. Further, the environmental conditions during the print test are unified to 25 ° C./55% RH.

Example 2 A colorless liquid composition B of this example consisting of the following components prepared in the same manner as liquid composition A, and an ink I using the same dye as that used in example 1 as a coloring material. Is used to configure an ink set according to the present invention, and under the same conditions as in Example 1,
Recording was performed on PPC paper (manufactured by Canon). Also in this example, the colorless liquid composition B was first ejected and first adhered to the recording paper, and then the ink I was adhered to perform the printing and recording. Components of Liquid Composition B- Polyallylamine hydrochloride (peak of molecular weight distribution = 700) 3 parts-Polyallylamine hydrochloride (peak of molecular weight distribution = 10,000) 5 parts-Thiodiglycol 10 parts-Lithium acetate 0.5 Parts / water 81.5 parts However, the pH of the liquid composition B was adjusted to 7.0 with NaOH.

Example 3 A colorless liquid composition C of this example, which was prepared in the same manner as the liquid composition A and consisted of the following components, and an ink I using the same dye as that used in Example 1 as a coloring material. Is used to configure an ink set according to the present invention, and under the same conditions as in Example 1,
Recording was performed on PPC paper (manufactured by Canon). Also in this example, the colorless liquid composition C was first ejected and first applied on the recording paper, and then the ink I was applied to perform the printing and recording. Components of liquid composition C • Polyallylamine hydrochloride (peak of molecular weight distribution = 10,000) 5 parts • Benzalkonium chloride 1 part • Thiodiglycol 10 parts • Urea 5 parts • Water 79 parts However, liquid composition B PH was adjusted to 6.0 with NaOH.

Example 4 A colorless liquid composition D of the present example consisting of the following components:
Ink I using the same dye as the coloring material used in Example 1
Was used to form an ink set according to the present invention, and recording was performed on PPC paper (manufactured by Canon Inc.) under the same conditions as in Example 1. Also in this example, the colorless liquid composition D was first ejected to be first deposited on the recording paper, and then the ink I was deposited to perform print recording. Components of liquid composition D- Polyallylamine hydrochloride (peak of molecular weight distribution = 10,000) 5 parts-Lauryltrimethylammonium chloride 1 part-Thiodiglycol 4 parts-Urea 5 parts-Water 79 parts However, liquid composition B The pH of was adjusted to 4.0 with NaOH.

Example 5 As described below, yellow, magenta, cyan and black color inks Y2, M2, C2 and B2 each containing a pigment and an anionic compound were obtained. This Y2, M
2, C2 and B2 were used as the ink II, and the ink set of this example was constituted with the colorless liquid composition A used in the example 1. Using this ink set, recording was performed on PPC paper (manufactured by Canon). In this example, the colorless liquid composition A was first ejected and first applied on the recording paper, and then the ink II was adhered to perform printing and recording. The recording head used here had a recording density of 360 dpi, and the driving condition was a driving frequency of 5 kHz. The ejection volume per dot was 45 pl for yellow, magenta and cyan inks, and a colorless liquid composition, and 60 pl for each black ink. The recording conditions are the same throughout the examples when the ink containing the pigment described below is used. Further, the environmental conditions during the print test are unified to 25 ° C./55% RH.

(Preparation of Ink II) Black Ink B2 anionic polymer P-1 (styrene-methacrylic acid-ethyl acrylate, acid value 400, weight average molecular weight 6,0)
00, an aqueous solution with a solid content of 20%, a neutralizing agent: potassium hydroxide) was used as a dispersant, and the following materials were charged into a batch type vertical sand mill (made by AIMEX) and 1 mm diameter glass beads were filled as a medium. The dispersion treatment was performed for 3 hours while cooling with water. The viscosity after dispersion was 9 cps and the pH was 10.0. This dispersion was centrifuged to remove coarse particles, to prepare a carbon black dispersion having a weight average particle diameter of 100 nm.

(Composition of carbon black dispersion) -P-1 aqueous solution (solid content 20%) 40 parts-Carbon black Mogul L (manufactured by Cablack) 24 parts-Glycerin 15 parts-Ethylene glycol monobutyl ether 0.5 parts- Isopropyl alcohol 3 parts / water 135 parts Next, the dispersion obtained above was sufficiently stirred to obtain an inkjet black ink B2 containing a pigment. The solid content of the final preparation was about 10%.

Yellow ink Y2 anionic polymer P-2 (styrene-acrylic acid-methyl methacrylate, acid value 280, weight average molecular weight 1
1,000%, an aqueous solution with a solid content of 20%, a neutralizing agent: diethanolamine) was used as a dispersant, and the following materials were used to carry out a dispersion treatment in the same manner as in the production of the black ink B2 to obtain a weight average particle diameter A 103 nm yellow color dispersion was prepared.

(Composition of yellow dispersion) P-2 aqueous solution (solid content 20%) 35 parts C.I. I. Pigment Yellow 180 (Novapalm Yellow PH-G, manufactured by Hoechst) 24 parts-Triethylene glycol 10 parts-Diethylene glycol 10 parts-Ethylene glycol monobutyl ether 1.0 part-Isopropyl alcohol 0.5 part-Water 135 parts

The above-obtained yellow dispersion was thoroughly stirred to obtain a pigment-containing yellow ink Y2 for ink jet. The final product has a solid content of about 1
It was 0%.

Cyan Ink C2 Using the anionic polymer P-1 used in the preparation of the black ink B2 as a dispersant, the following materials were used, and the same dispersion treatment as in the case of the carbon black dispersion described above was performed. Then, a cyan color dispersion having a weight average particle diameter of 120 nm was produced. (Composition of cyan color dispersion) P-1 aqueous solution (solid content 20%) 30 parts C.I. I. Pigment Blue 15: 3 (Fastgen Blue FGF, Dainichi Ink Chemical Co., Ltd.) 24 parts ・ Glycerin 15 parts ・ Diethylene glycol monobutyl ether 0.5 parts ・ Isopropyl alcohol 3 parts ・ Water 135 parts

The cyan color dispersion obtained above was sufficiently stirred to obtain a cyan ink C2 for ink jet containing a pigment. The solid content of the final preparation was about 9.6%.

Using the anionic polymer P-1 used in the preparation of the magenta ink M2 black ink B2 as a dispersant and the following materials, the same dispersion treatment as in the case of the carbon black dispersion described above. Then, a magenta color dispersion having a weight average particle diameter of 115 nm was produced. (Composition of magenta color dispersion) P-1 aqueous solution (solid content 20%) 20 parts C.I. I. Pigment Red 122 (Dainippon Ink and Chemicals) 24 parts ・ Glycerin 15 parts ・ Isopropyl alcohol 3 parts ・ Water 135 parts

The magenta color dispersion obtained above was thoroughly stirred to obtain a magenta ink M2 for ink jet containing a pigment. The solids content of the final preparation is about 9.2.
%Met.

Example 6 Ink II containing the pigment used in Example 5,
The colorless liquid composition B used in Example 2 was used to form the ink set of this example, and this was used to perform recording on PPC paper (manufactured by Canon Inc.) under the same conditions as in Example 5. In this example, the colorless liquid composition B was first ejected and first applied on the recording paper, and then the ink II was applied to perform printing and recording.

Example 7 Ink II containing the pigment used in Example 5,
The colorless liquid composition C used in Example 3 was used to form the ink set of this example, and this was used to perform recording on PPC paper (manufactured by Canon Inc.) under the same conditions as in Example 5. In this example, the colorless liquid composition C was first ejected and first adhered to the recording paper, and then the ink II was adhered to perform printing recording.

Example 8 Ink II containing the pigment used in Example 5,
The ink set of this example was constructed with the colorless liquid composition D used in Example 4, and recording was performed on PPC paper (manufactured by Canon Inc.) under the same conditions as in Example 5 using this. In this example, the colorless liquid composition D was first ejected and first applied on the recording paper, and then the ink II was applied to perform printing and recording.

Examples 9 to 16 Inks used in Examples 1 to 8 were used as the ink sets of this example by using the combinations of the colorless liquid compositions, respectively, and the ink was first adhered to the recording paper. Print recording was carried out in the same manner as in Example 1 or Example 5 except that the colorless liquid composition was post-printed.

The combinations of the colorless liquid compositions and the inks used in Examples 1 to 16 and which was recorded first are summarized in Table 1 below. Table 1 Contents of Examples 1 to 16

[0084]

[Evaluation] Each of the recorded images obtained in Examples 1 to 16 was evaluated by the following evaluation methods and evaluation criteria.

1. Image density A solid image was formed using a colorless liquid composition and black ink, and the reflection density after standing for 12 hours was measured by a reflection densitometer Macbeth RD915 (manufactured by Macbeth). The evaluation criteria are as follows. ⊚: Reflection density is 1.30 or more O: Reflection density is 1.25 or more and less than 1.30 Δ: Reflection density is 1.15 or more and less than 1.25 ×; Reflection density is less than 1.15

2. Fixability After forming a red solid image using a colorless liquid composition and yellow ink and magenta ink, another white paper is superposed on the recorded image by its own weight, and the image recorded on the back side of the paper is transferred. The time until the occurrence of stains and the occurrence of scumming were measured by setting the time at the end of recording as time zero, and used as a standard to measure the fixing property. The evaluation criteria are as follows. ⊚: Fixability is less than 20 seconds ◯: Fixability is 20 seconds or more and less than 30 seconds Δ: Fixability is 30 seconds or more and less than 40 seconds ×; Fixability is 40 seconds or more

3. Character Quality Black alphanumeric characters were printed using a colorless liquid composition and black ink and evaluated visually. When the feathering was hardly noticeable, it was marked with ⊚, when the feathering was slightly conspicuous but there was no practical problem, it was marked with ◯, and when it was lower than that, it was marked with x.

4. Bleeding Canon Color Bubble Jet Printer BJC-8
In the same printing mode as the printing mode E (1Pass, one-way printing) of 20J, the colorless liquid composition and the solid portions of the yellow, magenta, cyan, and black inks are printed adjacent to each other, and at the boundary of each color. The degree of bleeding was visually observed. The case where bleeding rarely occurred was marked with ⊚, the case where bleeding occurred slightly but there was a level where there was practically no problem was marked with ○, and other levels were marked with x.

5. Water resistance After printing solid images and alphanumeric characters of yellow, magenta, cyan and black inks and leaving them for 1 hour,
It was immersed in tap water having a water temperature of 20 ° C. for 10 seconds. Then, it was taken out from water, air-dried as it was, and visually evaluated for water resistance. Among yellow, magenta, cyan and black, the ink having the lowest water resistance was used as the water resistance evaluation result.
The water resistance evaluation criteria are as follows. ⊚: The recording agent did not flow out into the blank area, and scumming was hardly seen. In addition, there is almost no blurring of alphanumeric characters. ◯: Although the recording material flowed out to the margin part slightly and the alphanumeric characters were slightly blurred, it was at a level where there was no practical problem. X: The recording agent flows out to the margin portion, and the background stain is remarkable. Also, the blurring of alphanumeric characters is terrible. The area where the colorless liquid composition adheres to the recording medium in the above evaluation is the same area as the ink image forming area,
The printing duty is 100% for both the colorless liquid composition and the ink.

Table 2 shows the evaluation results of the images obtained in Examples 1 to 16 for the above-mentioned evaluation items. As is clear from Table 2, in Examples, images having good fixability, character quality, image density, bleeding, water resistance and ejection durability were obtained.

Table 2 Evaluation results

Example 17 To investigate the storage reliability of a colorless liquid composition, Example 1
The colorless liquid compositions A, B, C and D used in Example 16 were stored in glass bottles at 60 ° C. for 3 months, and the pH change of these liquid compositions after storage was examined. As a result,
As shown in Table 3, the liquid composition according to the present invention did not show a significant change in pH, even though it was stored at a high temperature. As a result, it is possible to eliminate the adverse effect on the inkjet recording device due to the decrease in the pH of the ink.

Table 3 Evaluation results for Example 17

Comparative Example 1 As a comparative example, a liquid composition for comparison in which lithium acetate and urea were removed from the composition components of the colorless liquid compositions A, B, C and D used in Examples 1 to 16 E, F, G and H were produced and the same storage test as in Example 17 was conducted.
The results are shown in Table 4, and it was confirmed that the pH drop after storage was remarkable.

Table 4 Evaluation results of Comparative Example 1

[0096]

As described above, according to the present invention, particularly in the case of performing color ink jet recording on plain paper, it is possible to obtain a high print quality and a sufficient image density while having a high-speed fixing property. Moreover, the uniformity of the solid image is also high, and a high-definition image with good color reproducibility can be obtained with bridging.
Moreover, an excellent ink jet recorded image can be provided in which the excellent image as described above completely satisfies the water resistance. Furthermore,
According to the present invention, the liquid composition has excellent long-term storage stability,
Even if the liquid composition after storage is used, there is no adverse effect and stable recording is possible.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a head portion of an inkjet recording apparatus.

FIG. 2 is a cross-sectional view of a head portion of an inkjet recording device.

FIG. 3 is an external perspective view of a head portion of the inkjet recording apparatus.

FIG. 4 is a perspective view showing an example of an inkjet recording apparatus.

FIG. 5 is a vertical sectional view of an ink cartridge.

FIG. 6 is a perspective view of a recording unit.

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 conceptual diagram showing an image forming method according to the present invention.

[Explanation of symbols]

 13: Head 14: Ink Grooves 15, 28: Heating Head 16: Protective Film 17-1, 17-2: Aluminum Electrode 18: Heating Resistor Layer 19: Heat Storage Layer 20: Substrate 21: Ink 22: Discharge Orifice (Fine Hole) ) 23: Meniscus 24: Ink droplet 25: Recording material 26: Multi groove 27: Glass plate 40: Ink bag 42: Rubber stopper 44: Ink absorber 45: Ink cartridge 51: Paper feed section 52: Paper feed Roller 53: Paper ejection roller 61: Blade 62: Cap 63: Ink absorber 64: Ejection recovery section 65: Recording head 66: Carriage 67: Guide shaft 68: Motor 69: Belt 70: Recording unit 71: Head section 72: Atmosphere Communication port

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area C08K 5/09 5/21 C09D 11/00 PSZ

Claims (13)

[Claims] 1. A liquid composition containing at least a cationic substance, containing at least polyallylamine,
A liquid composition comprising either lithium acetate or urea. 2. The cationic substance has a molecular weight distribution of 1,000 or less and 1,500 or more and 10,000 in a molecular weight distribution of the cationic substance measured by GPC.
The liquid composition according to claim 1, which has at least one peak in each of the following regions. 3. The cationic substance having a peak in the molecular weight range of 1,000 or less in the molecular weight distribution of the cationic substance measured by GPC is a cationic substance different from polyallylamine. The described liquid composition. 4. The liquid composition according to claim 1, which is used for image formation. 5. The liquid composition according to claim 1, comprising at least one ink selected from the ink group of each color of yellow, magenta, cyan, black, red, blue, and green, and in each color ink, An ink set containing a water-soluble dye containing at least an anionic group, or containing at least an anionic compound and a pigment. 6. The ink set according to claim 5, wherein three color inks of yellow, magenta and cyan are used. 7. The ink set according to claim 5, wherein four color inks of yellow, magenta, cyan and black are used. 8. The ink set according to claim 5, wherein the surface tension of the liquid composition is lower than the surface tension of each color ink. 9. A step (A) of adhering the liquid composition according to any one of claims 1 to 3 to an image forming area or an image forming area on a recording medium and its vicinity, and a water solution containing at least an anionic group. Image including a step (B) of ejecting an ink containing a functional dye or an ink containing at least an anionic compound and a pigment as droplets from a discharge orifice to a recording medium according to a recording signal. Forming method. 10. The image forming method according to claim 9, wherein the ink is ejected in the step (B) by an ink jet recording method. 11. The ink composition is used to attach the liquid composition to the recording medium in step (A).
The image forming method described in 1 .. 12. The image forming method according to claim 9, wherein step (A) is performed prior to step (B). 13. The image forming method according to claim 9, wherein the step (A) is performed after the step (B).