JP6443038B2 - Treatment liquid, image forming method, recorded matter, recording apparatus - Google Patents

Description

  The present invention relates to a processing liquid, an image forming method using the processing liquid, a recorded matter, and an ink jet recording apparatus.

In the image forming method by the ink jet method, a treatment liquid containing a cationic polymer is used to react with the pigment in the ink or to suppress the solubility of the pigment in order to improve the image quality such as high image density, prevention of back-through and bleeding. It is known to use
However, the conventional processing solution has a problem in that it improves the image quality while corroding a member in contact with the processing solution by chlorine ions which are counter ions of the cationic polymer, and it is costly to change the counter ions. Therefore, it has been necessary to deal with the components of the apparatus itself, processing and processing.
In order to prevent corrosion of the metal member in contact with the ink, a method of adding phosphate and citrate to the ink (Patent Document 1) and a method of adding butyl benzoate (Patent Document 2) are known. . However, none of them are inventions related to processing liquids, and of course, there is no description about using processing liquids for improving image quality.

Patent Document 3 discloses an invention in which a polyvalent metal salt and a benzoic acid are contained in a reaction solution for the purpose of preventing bleeding / back-through. However, the object is different from the present invention for the purpose of inhibiting corrosion. Further, in the present invention, benzoate is used as a rust preventive, whereas in the invention of Patent Document 3, a benzoic acid derivative is substantially used and benzoate is not used. The structure also differs in that a valent metal salt is included as an essential component.
Patent Document 4 discloses an invention in which a water-soluble cationic polymer is contained in a reaction solution for the purpose of preventing bleeding / back-through. However, the object of the present invention is different from that of the present invention, and there is no description regarding high-speed image formation or description regarding a rust inhibitor. Moreover, paragraph 0020 states that “the addition amount of the water-soluble cationic polymer is preferably 1 to 40% by mass, more preferably 3 to 30% by mass”, which is different from the present invention.
Patent Document 5 discloses that a citrate salt of a water-soluble aliphatic organic acid salt compound is contained in a reaction solution for the purpose of improving good image quality and abrasion resistance at high speed in printing on commercial printing paper. Disclosed inventions are disclosed. However, the purpose is different from that of the present invention, and citrate is used as a flocculant, and the role of citrate is different from that of the present invention used as a rust preventive.

The present invention provides a processing liquid to be applied before applying ink to a recording medium , and can prevent corrosion of a contacting member while ensuring good image quality even when the image forming speed is high. With the goal.

The treatment liquid contains a flocculant that breaks the dispersion of the ink and promotes the agglomeration. The chlorine ions contained as counter ions of the flocculant cause pitting corrosion on the passive film of the SUS (stainless steel) member. Reaction occurs and corrosion proceeds. In order to prevent corrosion, if the type of flocculant suitable for high image quality is changed to another, it is difficult to achieve the original high image quality. Moreover, if the counter ions are changed to ions other than chlorine ions, the cost increases.
Furthermore, if image formation is to be performed at a high speed of about 10 to 200 m / min, which is faster than the image formation speed of normal ink jet recording, it is necessary to increase the amount of flocculant added, and the progress of corrosion is accelerated.
As a result of the examination, when a phosphoric acid-based inorganic salt or p-tert-butylbenzoate is added to the treatment liquid, the phosphoric acid-based inorganic salt or p Since tert-butyl benzoate forms a new passive film, it has been found that the progress of corrosion of the member can be suppressed, and it is not necessary to change the type of aggregating agent, so that high image quality can be achieved. Was completed.

That is, the above problem is solved by the following invention 1).
1) A processing liquid applied before applying ink to a recording medium, wherein the processing liquid satisfies the following requirements [1] to [3].
[1] A water-soluble cationic polymer having a quaternary ammonium cation in the main chain and a chlorine ion as a counter ion (counter ion) , a phosphoric acid-based inorganic salt or p-tert-butylbenzoate, water Containing.
[2] The phosphoric acid-based inorganic salt is any of sodium monohydrogen phosphate, sodium dihydrogen phosphate, sodium polyphosphate, potassium monohydrogen phosphate, and potassium dihydrogen phosphate.
[3] Contains 40 to 60% by mass of the cationic polymer.

According to the present invention, a processing liquid that is applied before ink is applied to a recording medium and that can prevent corrosion of a contacting member while ensuring good image quality even when the image forming speed is high. Is obtained.

1 is a schematic diagram illustrating an example of an inkjet recording apparatus of the present invention. The schematic diagram which shows an example of the structure which apply | coats a pretreatment liquid in a pretreatment process part. The figure which shows the state which has ensured the printing area width | variety by arranging four head units short in the direction orthogonal to a conveyance direction in zigzag form. The enlarged view of head unit 304K-1.

上記式中、Ｒ１及びＲ２は、同一でも異なっていても良く、炭素数１〜８の、アルキル基、ヒドロキシアルキル基、アルケニル基、又はベンジル基を表す。
６） １）〜５）のいずれかに記載の処理液を記録媒体に付与する処理液付与工程と、処理液を付与された記録媒体に、インクジェット法により水性インクを吐出して画像を形成する画像形成工程を含むことを特徴とする画像形成方法。
７） 前記記録媒体が支持体の少なくとも一方の面上に塗工層を有するものであることを特徴とする６）に記載の画像形成方法。
８） ６）又は７）に記載の画像形成方法により画像が記録されたことを特徴とする記録物。
９） １）〜５）のいずれかに記載の処理液を記録媒体に付与する処理液付与手段と、処理液を付与された記録媒体に、インクジェット法により水性インクを吐出して画像を形成する画像形成手段を備えたことを特徴とするインクジェット記録装置。 Hereinafter, the present invention 1) will be described in detail. In addition, since the following 2) -9) is also included in embodiment of this invention 1), these are also demonstrated collectively.
2) The treatment liquid according to 1), further comprising citrate.
3) The treatment liquid according to 1) or 2), wherein the phosphoric acid-based inorganic salt contains at least sodium monohydrogen phosphate.
4) The treatment liquid according to any one of 1) to 3), wherein the p-tert-butyl benzoate includes a sodium salt or a potassium salt.
5) The treatment liquid according to any one of 1) to 4), wherein the cationic polymer has a repeating unit represented by the following general formula (1).
<General formula (1)>

In the above formula, R1 and R2 may be the same or different and each represents an alkyl group, a hydroxyalkyl group, an alkenyl group, or a benzyl group having 1 to 8 carbon atoms.
6) A treatment liquid applying step of applying the treatment liquid according to any one of 1) to 5) to a recording medium, and forming an image by ejecting aqueous ink onto the recording medium provided with the treatment liquid by an inkjet method. An image forming method comprising an image forming step.
7) The image forming method according to 6), wherein the recording medium has a coating layer on at least one surface of a support.
8) A recorded matter in which an image is recorded by the image forming method described in 6) or 7).
9) A processing liquid applying unit that applies the processing liquid according to any one of 1) to 5) to a recording medium, and an aqueous ink is ejected onto the recording medium to which the processing liquid is applied by an ink jet method to form an image. An ink jet recording apparatus comprising an image forming unit.

[Treatment solution]
The treatment liquid of the present invention contains the water-soluble cationic polymer as a flocculant, and a phosphoric acid-based inorganic salt or p-tert-butylbenzoic acid as a rust preventive agent for preventing corrosion of a member in contact with the treatment liquid Contains salt. In addition to these, known treatment liquid materials such as a water-soluble organic solvent, a solid wetting agent, a surfactant, a penetrating agent, a foam suppressor, and a pH adjuster may be added as appropriate.

<Aggregating agent (water-soluble cationic polymer having a quaternary ammonium cation in the main chain and a chlorine ion as a counter ion )>
The aggregating agent is used to obtain high image density and dot uniformity by breaking ink dispersion and promoting aggregation. As a result, bleeding and white spots can be prevented, and the image quality is improved.
The addition amount of the flocculant is 40 to 60% by mass of the entire treatment liquid. If it is less than 40% by mass, good image quality cannot be obtained when the image forming speed is faster than usual, which is about 10 to 200 m / min. On the other hand, if it exceeds 60% by mass, the viscosity becomes too high, which hinders handling.

The water-soluble cationic polymer having a quaternary ammonium cation in the main chain is not particularly limited, but polyamine-epichlorohydrin copolymer, polyamide-epichlorohydrin copolymer, dialkylallyl ammonium chloride polymer, dialkylaminoethyl (meth) acrylate quaternary. Ammonium salt polymers, modified polyvinyl alcohol dialkyl ammonium salt polymers, dialkyl diallylammonium salt polymers, and the like are preferred. Especially, what has a repeating unit represented by the said General formula (1) is preferable.
The weight average molecular weight of the polymer is preferably 500 to 1,000,000, more preferably 1,000 to 500,000, and still more preferably 1,000 to 10,000. If it is 500 or more, effective aggregating ability is obtained, and if it is 1,000,000 or less, it can be used as an aqueous solution.
The polyamine-epichlorohydrin copolymer is produced by polymerizing an amine and a monomer containing a carboxylic acid by a known method for polymerizing an amine and a monomer containing epichlorohydrin. And a known method of graft polymerization of a monomer containing epichlorohydrin.

<Rust preventive (Phosphate inorganic salt, p-tert-butyl benzoate)>
Phosphoric acid-based inorganic salt or p-tert-butyl benzoate forms a new passive film on the member where the passive film has been destroyed by chloride ions, which are counter ions of the flocculant. It plays a role of suppressing progress.
The addition amount of the phosphoric acid inorganic salt or p-tert-butyl benzoate is preferably 0.20 to 2.00% by mass, and more preferably 0.50 to 1.00% by mass of the entire treatment liquid. If it is the range of 0.20-2.00 mass%, sufficient corrosion inhibitory effect will be acquired.
The phosphoric acid-based inorganic salt or p-tert-butylbenzoate is used after being dissolved or dispersed in, for example, water, various water-soluble organic solvents, or a liquid medium thereof.

As the phosphoric acid-based inorganic salt, even when added to the treatment liquid, the pH of the treatment liquid does not increase excessively and does not inhibit the aggregation effect of the cationic polymer, so sodium monohydrogen phosphate, sodium dihydrogen phosphate, Sodium polyphosphate, potassium monohydrogen phosphate, and potassium dihydrogen phosphate are used. Of these, sodium monohydrogen phosphate is preferred. Even in the case of the same phosphoric acid type inorganic salt, in the case of lithium phosphate, potassium phosphate, and sodium phosphate, the pH of the treatment solution will increase excessively if it is added to such an extent that the basicity is strong and a corrosion inhibiting effect is obtained. There's a problem. If the pH is too high, the agglomeration effect of the cationic polymer is weakened, which affects beading. Although it is possible to adjust the pH by adding a pH adjuster, it is not preferable because it increases the cost and the salt may precipitate.
Examples of the p-tert-butylbenzoate include sodium p-tert-butylbenzoate, potassium p-tert-butylbenzoate, zinc p-tert-butylbenzoate, p-tert-butylbenzoic acid and triethanolamine. In view of safety and cost, sodium p-tert-butylbenzoate and potassium p-tert-butylbenzoate are preferable.

<Rust preventive (citrate)>
Phosphoric inorganic salt or p-tert-butyl benzoate has the above-mentioned effects, but when the passive film of a stainless steel member is destroyed, even a part of the passive film is not formed. In such a case, corrosion proceeds from that point.
In order to solve this problem, citrate plays a role of further suppressing the progress of the corrosion reaction by forming a chelate with iron ions eluted from the stainless steel member.
Examples of the citrate include sodium citrate, disodium citrate, trisodium citrate, potassium citrate, ammonium citrate, calcium citrate, lithium citrate, and aluminum citrate. Among these, disodium citrate is preferable from the viewpoints of safety, odor, and easiness of chelating of eluted iron ions.
The amount of citrate added is not particularly limited, but is preferably 0.10 to 2.00% by mass, and more preferably 0.50 to 1.00% by mass. If it is the range of 0.10-2.00 mass%, sufficient corrosion inhibitory effect will be acquired.

<Water-soluble organic solvent, solid wetting agent>
A water-soluble organic solvent and a solid wetting agent are added for the purpose of retaining moisture in the treatment liquid. Thereby, even when the water in the processing liquid evaporates in the processing liquid nozzle or the coating apparatus, an increase in the viscosity of the processing liquid is suppressed, and the discharge stability can be maintained. Therefore, it is preferable to use a water-soluble organic solvent and a solid wetting agent having a high equilibrium water content. Here, the equilibrium moisture content means that a mixture (solution) of a water-soluble organic solvent or a solid wetting agent and water is allowed to stand in air under a certain temperature and humidity condition, and evaporation of moisture in the solution and in air. The amount of water when the absorption of water into the solution is in an equilibrium state. Equilibrium water content in the present invention is a change in mass by adding 1 g of a water-soluble organic solvent or solid wetting agent to a petri dish in a desiccator maintained at a temperature of 23 ± 1 ° C. and a humidity of 80 ± 3% using a saturated aqueous solution of potassium chloride. After storing for a period until there is no more, it is obtained by the following formula.

Examples of water-soluble organic solvents and solid wetting agents include polyhydric alcohols, polyhydric alcohol alkyl ethers, polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, sulfur-containing compounds, and propylene. Examples include carbonate and ethylene carbonate. Among these, those having an equilibrium water content of 30% by mass or more are preferable, and 40% by mass or more of a water-soluble organic solvent (hereinafter referred to as “water-soluble organic solvent A”) is more preferable.
Polyhydric alcohols are particularly preferable, and examples thereof include 1,2,3-butanetriol, 1,2,4-butanetriol, glycerin, diglycerin, triethylene glycol, tetraethylene glycol, diethylene glycol, 1,3- Examples include butanediol. Among them, glycerin and 1,3-butanediol are particularly preferable because they have a low viscosity when containing water and can be kept stable without aggregating the colorant.
Use of the water-soluble organic solvent A in an amount of 50% by mass or more of the total amount of the water-soluble organic solvent and the solid wetting agent is preferable in that the discharge stability of the processing liquid is improved and the fixing of the processing liquid to the recording apparatus can be prevented.

Instead of the water-soluble organic solvent A or in addition to the water-soluble organic solvent A, a water-soluble organic solvent having an equilibrium water content of less than 30% by mass and / or a solid wetting agent may be used in combination.
Examples thereof include saccharides in addition to the water-soluble organic solvent and the compounds mentioned as the solid wetting agent.
Specific examples of the polyhydric alcohols include dipropylene glycol, 1,5-pentanediol, 3-methyl-1,3-butanediol, propylene glycol, 2-methyl-2,4-pentanediol, ethylene glycol, Examples include tripropylene glycol, hexylene glycol, polyethylene glycol, polypropylene glycol, 1,6-hexanediol, 1,2,6-hexanetriol, trimethylolethane, and trimethylolpropane.

Specific examples of the polyhydric alcohol alkyl ethers include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, ethylene glycol mono-2-ethylhexyl ether, propylene glycol monoethyl. Examples include ether.
Specific examples of the polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.
Specific examples of the nitrogen-containing heterocyclic compound include 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone, and the like.

Specific examples of the amides include formamide, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide and the like.
Specific examples of the amines include monoethanolamine, diethanolamine, triethanolamine, N, N-dimethylmonoethanolamine, N-methyldiethanolamine, N-methylethanolamine, N-phenylethanolamine, 3-aminopropyldiethylamine. Etc.
Specific examples of the pre-sulfur-containing compounds include dimethyl sulfoxide, sulfolane, thiodiglycol and the like.

Examples of the saccharide include monosaccharides, disaccharides, oligosaccharides (including trisaccharides and tetrasaccharides), polysaccharides, and the like. Specific examples thereof include glucose, mannose, fructose, ribose, xylose, arabinose, galactose, maltose, cellobiose, lactose, sucrose, trehalose, maltotriose, and the like. Here, the polysaccharide means a saccharide in a broad sense, and is used to include a substance that exists widely in nature, such as α-cyclodextrin and cellulose. In addition, the derivatives of these saccharides are represented by reducing sugars of the saccharides {for example, sugar alcohol [general formula: HOCH ₂ (CHOH) _n CH ₂ OH (where n is an integer of 2 to 5)]. }, Oxidized sugar (for example, aldonic acid, uronic acid, etc.), amino acid, thioic acid and the like. Among these, sugar alcohols are preferable, and specific examples include maltitol and sorbit.

  The addition amount of the water-soluble organic solvent and the solid wetting agent is not particularly limited, but is preferably 5 to 80% by mass, and more preferably 10 to 20% by mass based on the entire treatment liquid. If the amount is 80% by mass or less, the drying property of the recording medium to which the treatment liquid is attached does not deteriorate depending on the type of the water-soluble organic solvent or the solid wetting agent, and the aggregation ability of the treatment liquid does not greatly decrease. Moreover, if it is 5 mass% or more, the water | moisture content contained in a processing liquid will evaporate, the viscosity of a processing liquid will rise, and a malfunction will not arise in an application | coating process.

<Surfactant>
The surfactant is added to improve the wettability of the treatment liquid to the recording medium.
The addition amount of the surfactant is preferably 0.001 to 5% by mass, more preferably 0.05 to 2% by mass, based on the entire treatment liquid. If it is 0.001 mass% or more, the addition effect of surfactant will be acquired. However, even if added in excess of 5% by mass, an effect cannot be expected.
Examples of the surfactant include a fluorine-based surfactant, a silicone-based surfactant, a nonionic surfactant, an anionic surfactant, and a betaine-based surfactant, and a fluorine-based surfactant is preferable. These surfactants may be used alone or in combination of two or more.
As the fluorine-based surfactant, those having 2 to 16 carbon atoms substituted with fluorine are preferable, and those having 4 to 16 carbon atoms are more preferable. If the number of carbons is 2 or more, the effect of using a fluorosurfactant is obtained, and if it is 16 or less, problems such as storage stability do not occur.
Examples of fluorosurfactants include perfluoroalkyl sulfonic acid compounds, perfluoroalkyl carboxylic acid compounds, perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, and perfluoroalkyl ether groups in the side chain. And polyoxyalkylene ether polymer compounds. Among these, a fluorosurfactant having a perfluoroalkyl group is preferable.

<Penetration agent>
The penetrating agent is added to improve the permeability of the processing liquid into the recording medium.
The amount of penetrant added is preferably 0.1 to 5.0% by mass. If it is 0.1 mass% or more, the effect of penetrating the treatment liquid can be obtained. Moreover, if it is 5.0 mass% or less, a penetrant will not isolate | separate from a solvent and a permeability improvement effect will not be saturated.
As the penetrant, a non-wetting agent polyol compound or glycol ether compound having 8 to 11 carbon atoms is preferable, and one having a solubility of 0.2 to 5.0 mass% in water at 25 ° C is preferable. Among these, 2-ethyl-1,3-hexanediol [solubility: 4.2% (25 ° C.)], 2,2,4-trimethyl-1,3-pentanediol [solubility: 2.0% (25 ° C)] is particularly preferred.

Examples of other non-wetting agent polyol compounds include 2-ethyl-2-methyl-1,3-propanediol, 3,3-dimethyl-1,2-butanediol, and 2,2-diethyl-1,3. -Propanediol, 2-methyl-2-propyl-1,3-propanediol, 2,4-dimethyl-2,4-pentanediol, 2,5-dimethyl-2,5-hexanediol, 5-hexene-1 And aliphatic diols such as 2-diol.
Other penetrants that can be used in combination are not particularly limited as long as they can be dissolved in a treatment solution and adjusted to desired physical properties, and are appropriately selected according to the purpose. For example, diethylene glycol monophenyl ether, ethylene glycol Alkyl and aryl ethers of polyhydric alcohols such as monophenyl ether, ethylene glycol monoallyl ether, diethylene glycol monophenyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, tetraethylene glycol chlorophenyl ether, lower alcohols such as ethanol, etc. Can be mentioned.

<Foam suppressant>
The antifoaming agent is added to suppress foaming of the treatment liquid. In general, liquids with high surface tension, such as water, are difficult to foam because of the force to reduce the surface area of the liquid as much as possible. However, liquids with low surface tension and high viscosity are easy to foam, and the generated bubbles disappear. It is hard to do. When the treatment liquid of the present invention contains the water-soluble cationic polymer, the water-soluble organic solvent, the surfactant, etc., it is preferable to add a foam suppressant because the surface tension is lowered and the viscosity is increased and the foam is easily foamed. .
0.01-10 mass% is preferable and, as for the addition amount of a foam suppressor, 0.02-5 mass% is more preferable. If it is 0.01 mass% or more, the effect which suppresses a bubble is fully acquired. Moreover, if it is 10 mass% or less, an antifoamer will not be dissolved in a processing liquid.

<PH adjuster>
The pH adjuster is not particularly limited as long as it can adjust the pH to 6 to 10 without adversely affecting the prepared treatment liquid, and can be appropriately selected according to the purpose. When the pH is 10 or less, the aggregation effect is not greatly reduced. Moreover, if pH is 6 or more, the roller of the conveyance member which contacts a process liquid will corrode, and a trouble will not generate | occur | produce in a conveyance function.
Preferred pH adjusters include alcohol amines, alkali metal hydroxides, ammonium hydroxides, phosphonium hydroxides, alkali metal carbonates, and the like.
Examples of the alcohol amines include diethanolamine, triethanolamine, 2-amino-2-ethyl-1,3-propanediol, and the like. Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, and potassium hydroxide. Examples of the ammonium hydroxide include ammonium hydroxide and quaternary ammonium hydroxide. Examples of the phosphonium hydroxide include quaternary phosphonium hydroxide. Examples of the alkali metal carbonate include lithium carbonate, sodium carbonate, and potassium carbonate.

[ink]
The ink used in the image forming method of the present invention is not particularly limited, and may be a known ink containing a colorant, a water-soluble organic solvent, a surfactant, a penetrating agent, a water-dispersible resin, and the like.
The viscosity of the ink is preferably 5 to 20 mPa · s at 25 ° C. When the viscosity is 5 mPa · s or more, the density and quality of the recorded image are improved. Moreover, if the viscosity is 20 mPa · s or less, good ejection stability can be obtained. The viscosity can be measured using a viscometer manufactured by Toki Sangyo Co., Ltd .: RE-550L.
The surface tension of the ink is preferably 20 to 35 mN / m at 25 ° C., more preferably 20 to 30 mN / m. When the surface tension is 20 to 35 mN / m, the permeability of the ink is increased, the drying property is good even when recording on plain paper, and color bleeding is reduced. Further, it becomes easy to get wet with the treatment liquid adhering portion of the recording medium, the saturation of the recorded matter is increased, and white spots are also improved. If the surface tension exceeds 35 mN / m, leveling of the ink on the recording medium is difficult to occur and the drying time may be prolonged.

<Colorant>
As the colorant, a pigment is mainly used from the viewpoint of weather resistance. However, in order to adjust the color tone, a dye may be used in combination as long as the weather resistance is not deteriorated.
There is no restriction | limiting in particular as a pigment, Although it can select suitably according to the objective, A black or a color inorganic pigment, an organic pigment, etc. are mentioned. These pigments may be used alone or in combination of two or more.
The content of the colorant in the ink is preferably 2 to 15% by mass and more preferably 3 to 12% by mass in terms of solid content. If it is 2% by mass or more, the saturation and density of the recorded matter will not be lowered, and if it is 15% by mass or less, the viscosity of the ink will be high and the ejection stability will not be lowered. The solid content in the ink can be measured by a known method, and examples thereof include a method of separating only the water-dispersible colorant and the water-dispersible resin component from the ink.

The inorganic pigment was produced by a known method such as titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow, or a contact method, furnace method, thermal method, or the like. Carbon black etc. are mentioned.
Examples of the organic pigment include azo pigments (including azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments), polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, And dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinofullerone pigments, etc.), dye chelates (for example, basic dye chelate, acidic dye chelate, etc.), nitro pigments, nitroso pigments, aniline black, and the like. Of these, those having good affinity for water are particularly preferable.

Specific examples of preferable pigments include carbon blacks such as furnace black, lamp black, acetylene black, and channel black (CI pigment black 7), copper, iron (CI pigment black 11) for black. And metal pigments such as titanium oxide, and organic pigments such as aniline black (CI Pigment Black 1).
For color use, C.I. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 408, 109, 110, 117, 120, 128, 138, 150, 151, 153, 183, C.I. I. Pigment orange 5, 13, 16, 17, 36, 43, 51, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48: 2, 48: 2 (Permanent Red 2B (Ca)), 48: 3, 48: 4, 49: 1, 52: 2, 53: 1, 57: 1 (Brilliant Carmine 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81, 83, 88, 101 (Bengara), 104, 105, 106, 108 ( Cadmium red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 185, 190, 193, 209, 219, C.I. I. Pigment violet 1 (rhodamine lake), 3, 5: 1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15, 15: 1, 15: 2, 15: 3 (phthalocyanine blue), 16, 17: 1, 56, 60, 63, C.I. I. Pigment green 1, 4, 7, 8, 10, 17, 18, 36, and the like.

<Water-soluble organic solvent>
The water-soluble organic solvent used in the ink is not particularly limited, but the water-soluble organic solvent for the treatment liquid described above is preferable. The mass ratio of the water-dispersible colorant and the water-soluble organic solvent in the ink affects the ink ejection stability from the head. For example, if the water-dispersible colorant has a large solid content but the blending amount of the water-soluble organic solvent is small, water evaporation near the ink meniscus of the nozzle may progress and cause ejection failure.
The content of the water-soluble organic solvent in the ink is preferably 20 to 50% by mass, and more preferably 20 to 45% by mass. When the content is 20% by mass or more, the ejection stability does not decrease, and the waste ink does not adhere to the recording apparatus maintenance apparatus. Moreover, if it is 50 mass% or less, the drying property on a paper surface will not fall or the quality of a recorded matter will not fall.

<Surfactant>
As the surfactant used in the ink, the surfactant used in the treatment liquid described above is preferable. Among them, it is preferable to select a water dispersible colorant and a combination with a water-soluble organic solvent that do not impair dispersion stability, have low surface tension, and have high penetrability and leveling properties. Specifically, anionic surfactants, nonionic surfactants, silicone surfactants and fluorosurfactants are preferred, and silicone surfactants and fluorosurfactants are particularly preferred. These surfactants may be used alone or in combination of two or more.
The content of the surfactant in the ink is preferably 0.01 to 3.0% by mass, and more preferably 0.5 to 2% by mass. If it is 0.01 mass% or more, the effect of addition of a surfactant is sufficiently obtained. On the other hand, when the content is 3.0% by mass or less, the permeability to the recording medium is unnecessarily high, and the density of the recorded image does not decrease or the back-through occurs.

<Penetration agent>
As the penetrant used in the ink, the penetrant used in the treatment liquid described above is preferable. The content of the penetrant in the ink is preferably 0.1 to 4.0% by mass. When the content is 0.1% by mass or more, the dryness is deteriorated and bleeding does not occur in the recorded image. On the other hand, when the content is 4.0% by mass or less, the dispersion stability of the colorant is impaired, the nozzle of the recording apparatus is easily clogged, or the permeability to the recording medium is increased more than necessary. There is no reduction in the concentration of the material and no occurrence of strikethrough.

<Water dispersible resin>
The water-dispersible resin is used to increase the water repellency, water resistance and weather resistance of the recorded image, and to increase the density and saturation by forming a film on the surface to which the ink is attached.
Examples of the water-dispersible resin include condensation-type synthetic resins, addition-type synthetic resins, and natural polymer compounds. Two or more of these may be used in combination.
Examples of the condensed synthetic resin include polyester resin, polyurethane resin, polyepoxy resin, polyamide resin, polyether resin, poly (meth) acrylic resin, acrylic-silicone resin, and fluorine-based resin.
Examples of the additional synthetic resin include polyolefin resins, polystyrene resins, polyvinyl alcohol resins, polyvinyl ester resins, polyacrylic acid resins, unsaturated carboxylic acid resins, and the like.
Examples of the natural polymer compound include celluloses, rosins, and natural rubber. Among these, polyurethane resin fine particles, acrylic-silicone resin fine particles, and fluorine-based resin fine particles are particularly preferable.
The water dispersible resin may be a homopolymer or a copolymer, and may be any of a single phase structure type, a core shell type, and a power feed type emulsion.

As the water-dispersible resin, the resin itself has a hydrophilic group and has a self-dispersibility, or the resin itself does not have a dispersibility and is given a dispersibility by a surfactant or a resin having a hydrophilic group. . Among these, an emulsion of resin particles obtained by emulsion and suspension polymerization of an ionomer of a polyester resin or a polyurethane resin or an unsaturated monomer is preferable.
The water-dispersible resin has a pH of 4 to 12 before being blended with the ink, particularly in water, since it causes breakage of molecular chains such as dispersion breakage and hydrolysis under strong alkali or strong acidity. From the viewpoint of miscibility with the dispersible colorant, the pH is more preferably 6 to 11, and further preferably 7 to 9.
The average particle diameter (D50) of the water-dispersible resin is related to the viscosity of the dispersion. When the composition and the solid content are the same, the viscosity increases as the particle diameter decreases. Therefore, the average particle diameter (D50) of the water-dispersible resin is preferably 50 nm or more so that the viscosity does not become too high when ink is used. Further, when the particle diameter is several tens of μm, it becomes larger than the diameter of the nozzle of the head of the recording apparatus. Such large particles are present in the ink, thereby deteriorating the ejection stability. Therefore, in order to ensure ink ejection stability, the average particle size (D50) of the water-dispersible resin is preferably 200 nm or less, and more preferably 150 nm or less.

  Further, since the water-dispersible resin has a function of fixing the water-dispersible colorant to the recording medium, it is preferable to form a film at room temperature. Therefore, the minimum film forming temperature of the water dispersible resin is preferably 30 ° C. or lower. The glass transition temperature of the water dispersible resin is preferably −40 ° C. or higher, and more preferably −30 ° C. or higher. If the glass transition temperature is −40 ° C. or higher, the viscosity of the resin film will not be so strong that tackiness (stickiness, stickiness) will not occur on the recorded matter. The content of the water-dispersible resin in the ink is preferably 1 to 15% by mass and more preferably 2 to 7% by mass or less in terms of solid content.

<Other ingredients>
In addition to the above components, pH adjusters, antiseptic / antifungal agents, chelating agents, rust inhibitors, antioxidants, ultraviolet absorbers, oxygen absorbers, light stabilizers, etc. are added to the ink as necessary. You may do it.
(PH adjuster)
The pH adjuster is not particularly limited as long as it can adjust the pH of the ink to 7 to 11 without adversely affecting the prepared ink, and can be appropriately selected according to the purpose. If the pH of the ink is in the above range, the ink does not melt the recording device head or the ink supply unit, causing deterioration or leakage of the ink, or problems such as ejection failure.
As a pH adjuster, the same thing as the case of the processing liquid mentioned above can be used.

(Antiseptic and antifungal agent)
Examples of antiseptic / antifungal agents include sodium dehydroacetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, sodium benzoate, sodium pentachlorophenol, 1,2-benzisothiazolin-3-one sodium compound, and the like. Can be mentioned.
(Chelating reagent)
Examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, sodium uramil diacetate, and the like.

(Rust inhibitor)
Examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite, 1,2,3-benzotriazole, and the like.
(Antioxidant)
Examples of the antioxidant include phenol-based antioxidants (including hindered phenol-based antioxidants), amine-based antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, and the like.
(UV absorber)
Examples of the UV absorber include benzophenone UV absorbers, benzotriazole UV absorbers, salicylate UV absorbers, cyanoacrylate UV absorbers, nickel complex salt UV absorbers, and the like.

[recoding media]
The treatment liquid of the present invention is particularly effective for a recording medium (coated paper) having a coating layer. There is no restriction | limiting in particular as a coated paper, According to the objective, it can select suitably. Here, the coated paper refers to a paper in which a paint is applied to the surface of the base paper (support) to enhance the aesthetics and smoothness, and may be a front / back double-sided coating or a single-sided coating. The paint is a mixture of a white pigment such as kaolin or calcium carbonate and a binder such as starch. Examples of coated paper include art paper, coated paper, lightweight coated paper, cast paper, and fine coated paper.
The coated paper usually has a transfer amount of pure water of 1 to 10 mL / m ² at a contact time of 100 ms measured with a dynamic scanning absorption meter. A dynamic scanning absorption meter (for example, K350 series D type manufactured by Kyowa Seiko Co., Ltd.) is an apparatus that can accurately measure the amount of liquid absorption in an extremely short time.

[Image forming method]
The image forming method of the present invention includes a step of attaching a treatment liquid to a recording medium, and a step of forming an image by ejecting and attaching ink to the recording medium by an ink jet method. Further, a process of drying the processing liquid attached to the recording medium may be provided between the processing liquid attaching process and the image forming process.

<Process to attach treatment liquid>
The step of attaching the treatment liquid is not particularly limited as long as it is a method capable of uniformly attaching the treatment liquid to the surface of the recording medium. Examples include blade coating, gravure coating, gravure offset coating, bar coating, roll coating, knife coating, air knife coating, comma coating, U comma coating, AKKU coating, and smoothing coating. , Micro gravure coating method, reverse roll coating method, 4 to 5 roll coating method, dip coating method, curtain coating method, slide coating method, die coating method and the like.
Wet adhesion amount of the processing liquid to the recording medium (attached amount of the processing solution prior to drying of the recording medium) is preferably ^{0.1~10.0g / m 2, 1.0~3.0g / m} 2 Gayori preferable. If the wet adhesion amount is 0.1 g / m ² or more, the image quality (density, saturation, color bleeding, feathering) of the recorded matter is improved, and if it is 10.0 g / m ² or less, the recorded matter is obtained. The texture is not impaired, and there is no problem in terms of cost. In addition, since the aggregation effect is saturated at about 10.0 g / m ² , it is meaningless to increase the adhesion amount beyond this.

<Step of drying the attached treatment liquid>
As the process of drying the treatment liquid adhered to the recording medium, the pretreatment liquid adhered to the recording medium is transferred to the conveyance member that comes in contact from the treatment liquid adhesion process to image formation by ink ejection, and the conveyance member is obstructed. In other words, an artificial drying method may be used to such an extent that image quality is not deteriorated due to accumulation of dirt and dirt. The drying temperature is preferably 40 ° C to 130 ° C, more preferably 80 ° C to 100 ° C. If it is 40 ° C. or higher, drying does not take too long, and if it is 130 ° C. or lower, there is no abnormality in the recording medium.
Examples of the drying method include a heat drum method, an oven method, a hot air blowing method, a preheater method, and a heating roller method. Moreover, you may combine these systems.
Note that “drying” after applying the treatment liquid does not mean that the treatment liquid is absorbed into the recording medium and apparently becomes dry, but liquid such as moisture in the pretreatment liquid evaporates. It means that it cannot solidify and solidifies.

<Process for forming an image by attaching ink>
The step of forming an image by adhering ink is a step of ejecting and adhering ink to the recording medium to which the processing liquid is attached or the recording medium that has undergone the processing liquid drying step. As the method, a method in which stimulation (energy) is applied to the ink by a predetermined apparatus and the ink is ejected and adhered, and various known ink jet recording methods can be employed. Examples thereof include an ink jet recording method in which an image is recorded on a continuous recording medium by a single pass method using a lined head, and an ink jet recording method in which a head is scanned.
There is no particular limitation on the driving method of the recording head, which is a means for ejecting ink. Examples of driving methods include piezoelectric element actuators using PZT (lead zirconate titanate), thermal energy application methods, on-demand type heads using electrostatic force actuators, etc., continuous injection And a method of recording with a charge control type head of the mold. In the method of applying thermal energy, it is difficult to freely control the ejection of droplets, and the variation in the quality of images recorded depending on the type of recording medium tends to be large. When applied to a recording medium, this problem is solved, and a stable and high quality recorded matter can be obtained regardless of the type of recording medium.

The image forming method of the present invention is particularly preferably applicable to an inkjet recording apparatus that performs inkjet recording by conveying a recording medium at high speed.
That is, when the recording medium is transported at a high speed of, for example, 10 to 200 m / min by the transport member, the transport is performed by performing a series of steps of applying a specific treatment liquid, drying, and applying ink as in the present invention. It is possible to suppress deterioration in image quality due to failure of members and accumulation of dirt, and it is possible to obtain an effect that image quality does not deteriorate even when forced drying is performed.

[Inkjet recording apparatus]
An example of the ink jet recording apparatus of the present invention will be described with reference to the schematic view of FIG.
The ink jet recording apparatus 300 includes a recording medium transport unit 301, a pretreatment process unit 302 that applies a pretreatment liquid to the recording medium 203, an image formation process part 304, and a posttreatment that applies a posttreatment liquid to a recording medium that has undergone the image formation process. The process part 305 is comprised.
The recording medium conveyance unit 301 includes a paper feeding device 307, a plurality of conveyance rollers, and a winding device 308. The recording medium 203 in FIG. 1 is an example of continuous paper (roll paper) wound in a roll shape. The recording medium 203 is unwound from a paper feeding device by a transport roller, and is transported on a platen to be taken up by a winding device 308. Is wound up by.

<Pretreatment process part>
A pretreatment liquid is applied to the recording medium 203 conveyed from the recording medium conveyance unit 301 by the pretreatment process unit 302. In inkjet, if an image is formed on a recording medium other than dedicated inkjet paper, quality problems such as bleeding, density, color tone and show-through, and problems related to image fastness such as water resistance and weather resistance may occur. In order to improve image quality, a pretreatment liquid having an ink aggregating function is applied before forming an image on a recording medium.
In the pretreatment step, the pretreatment liquid is uniformly applied to the surface of the printing paper, but the application method is not particularly limited. Examples thereof include a blade coating method, a gravure coating method, a gravure offset coating method, a bar coating method, and a roll coating method.

FIG. 2 is a schematic diagram illustrating an example of a configuration in which a pretreatment liquid is applied in the pretreatment process unit 302. Although the roll coating method will be described here, other pretreatment liquid coating methods may be used.
As shown in FIG. 2, the recording medium 203 is conveyed into the pretreatment liquid coating apparatus 204 by a conveyance roller (not shown). A pretreatment liquid 205 is stored in the pretreatment liquid coating apparatus 204, and the pretreatment liquid 205 is transferred to the roller surface of the application roller 208 in a thin film form by a stirring / supply roller 206 and transfer / thinning rollers 207a and 207b. The Then, the application roller 208 rotates while being pressed against the rotating counter roller 201, and the recording medium 203 passes between them, so that the pretreatment liquid 205 is applied to the surface.
Further, the counter roller 201 can adjust the nip pressure when the pretreatment liquid is applied by the pressure adjusting device 209, thereby changing the application amount of the pretreatment liquid 205. Further, the coating amount can be adjusted by changing the rotation speed of the coating roller 208. The application roller 208 and the platen roller 202 are driven by a power source such as a drive motor (not shown), and the amount of application can be adjusted by changing the rotational speed by changing the energy of the power source.
As described above, the method of applying the pretreatment liquid 205 for improving the image quality to the recording area of the recording medium 203 with the application roller 208 is compared with the method of spraying the processing agent liquid onto the recording medium using the ejection head. The pretreatment liquid 205 having a relatively high viscosity can be thinly applied onto the recording medium 203, and image bleeding and the like can be further reduced.

  Moreover, you may provide the pre-processing post-drying part 303 in the pre-processing part after an application | coating process like FIG. The pre-processing and post-drying apparatus includes, for example, heat rollers 311 and 312 as shown in FIG. According to this apparatus, the recording medium 203 coated with the pretreatment liquid is transported to the heat rollers 311 and 312 by the transport roller. The heat rollers 311 and 312 are heated to a high temperature of 50 to 100 ° C., and the recording medium 203 coated with the pretreatment liquid evaporates and dries due to contact heat transfer from the heat rollers 311 and 312. The drying means is not limited to this, and an infrared drying device, a microwave drying device, a hot air device, or the like may be used. Alternatively, for example, a heat roller and a hot air device may be combined. Although not shown, it is also effective to heat the recording medium (addition of a preheating step) before applying the pretreatment liquid.

<Image forming process section>
On the recording medium after the pretreatment process, an image corresponding to the image data is formed in the image forming process section. The image forming process unit 304 is a full-line head, and four recording heads that can handle black (K), cyan (C), magenta (M), and yellow (Y) from the upstream side in the recording medium conveyance direction. 304K, 304C, 304M, and 304Y are provided. For example, as shown in FIG. 3, the black (K) recording head 304K has four head units 304K-1, 304K-2, 304K-3, and 304K-4 that are short in the direction orthogonal to the transport direction. The print area width is secured by arranging them. FIG. 4 is an enlarged view of the head unit 304K-1. As shown in FIG. 4, a large number of print nozzles 310 are arranged along the longitudinal direction of the head unit 304K-1 to form a nozzle row on the nozzle surface 309 of 304K-1. In this example, the number of nozzle rows is one, but a plurality of rows can be provided. The other recording heads 304C, 304M, and 304Y have the same configuration, and the four recording heads 304K, 304C, 304M, and 304Y are arranged in the transport direction while maintaining the same pitch. As a result, it is possible to form an image over the entire print area width in a single recording operation.

<Post-processing process part>
A post-processing liquid is applied to the recording medium after the image forming process by a post-processing unit 305 as necessary. The post-treatment liquid described later contains a component that can form a transparent protective layer on the recording medium 203. In the post-processing step, it may be applied over the entire image surface of the recording medium 203 or may be applied only to a specific portion of the image surface. However, it is desirable to change the coating amount and coating method according to the printing conditions (such as the type of recording medium and the amount of ink ejected onto the paper).

<Drying process>
After the image formation or after the post-processing step, a drying step 306 is provided as shown in FIG.
The drying process includes, for example, heat rollers 313 and 314 as shown in FIG. 1 and hot air blowing nozzles. After image formation or post-processing, the recording medium 203 is conveyed to the heat rollers 313 and 314 by the conveyance roller. The heat rollers 313 and 314 are heated to a high temperature, and the recording medium 203 coated with the post-treatment liquid evaporates and dries due to contact heat transfer from the heat rollers 313 and 314. Further downstream, a hot air device is provided as a drying means. In addition, an infrared drying device, a microwave drying device, or the like may be used.
The recording medium 203 after drying is taken up by the take-up device 308. However, if the pressing force during take-up is large, a phenomenon such as picking in which an image is transferred to the back surface may occur. However, if the drying efficiency is improved, such transfer can be reduced even when an image with a large amount of ink is printed at high speed. It is also possible to additionally provide a pre-winding drying unit 315 as shown in FIG.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated further more concretely, this invention is not limited by these Examples. In the examples, “%” is “mass%”.

<Preparation of cationic polymer>
A cationic polymer was prepared as follows and the physical properties were measured.
(Measurement of physical properties)
-The solid content concentration was determined by using a hot air circulating thermostat (ETAC HIFLEX FX422P manufactured by Enomoto Kasei Co., Ltd.) for 3 hours at 105 ° C., and then determining the solid content using the heat loss as a volatile component.
Viscosity was measured at 25 ° C. using a viscometer (RE-550L, manufactured by Toki Sangyo Co., Ltd.).
-Weight average molecular weight is GPC (HLC-8320GPC EcoSEC, manufactured by Tosoh Corporation), 0.1 mol / L phosphate buffer (pH 2.1) is used as eluent, column temperature is 40 ° C, flow rate is 1.0 mL / It measured by min and converted into molecular weight using PEG (polyethylene glycol) as a standard sample.

(Production Example 1)
A 1000 mL glass autoclave equipped with a stirrer, thermometer, and nitrogen gas inlet tube was charged with 200.0 g (2.218 mol) of 50% dimethylamine and 291.0 g (1.477 mol) of 30% trimethylamine, After substituting with nitrogen, 274.0 g (2.961 mol) of epichlorohydrin was added over 2 hours while cooling to 40 ° C., reacted at 40 ° C. for 1 hour, further heated to 80 ° C. and aged for 3 hours. I let you.
After cooling, the pH was adjusted to 5.0 with 77.0 g of 35% hydrochloric acid and 0.82 g of 75% phosphoric acid (vs. solid content of 730 ppm), and a cation having a solid content concentration of 58%, a viscosity of 21 mPa · s, and a weight average molecular weight of 3000 A polymer was obtained.

(Production Example 2)
The same autoclave as in Production Example 1 was charged with 200.0 g (2.218 mol) of 50% dimethylamine and 174.8 g (0.887 mol) of 30% trimethylamine, purged with nitrogen, and then cooled to 40 ° C. 246.0 g (2.659 mol) of chlorohydrin was added over 2 hours, reacted at 40 ° C. for 1 hour, further heated to 80 ° C. and aged for 3 hours.
After cooling, the pH was adjusted to 5.0 with 46.2 g of 35% hydrochloric acid and 0.87 g of 75% phosphoric acid to obtain a cationic polymer having a solid content concentration of 60%, a viscosity of 40 mPa · s, and a weight average molecular weight of 6800.

(Production Example 3)
The same autoclave as in Production Example 1 was charged with 200.0 g (2.218 mol) of 50% dimethylamine and 218.5 g (1.109 mol) of 30% trimethylamine, purged with nitrogen, and then cooled to 40 ° C. with epi. 257.0 g (2.777 mol) of chlorohydrin was added over 8 hours, reacted at 40 ° C. for 4 hours, further heated to 80 ° C. and aged for 10 hours.
After cooling, the pH was adjusted to 5.0 with 54.5 g of 35% hydrochloric acid and 0.92 g of 75% phosphoric acid to obtain a cationic polymer having a solid content concentration of 50%, a viscosity of 546 mPa · s, and a weight average molecular weight of 13,000.

Examples 1-18, 21-32, Comparative Examples 1-6
Using the materials shown in the columns of Examples and Comparative Examples in Table 1-1 to Table 3 below including the cationic polymers of Preparation Examples 1 to 3, the mixture was stirred for 20 minutes using a stirrer in a 100 mL beaker. Thus, a treatment liquid was prepared.
In addition, for "* 1" in the table, an appropriate amount is added so that the pH is 7 to 9, and for "* 2", the active ingredient is concentrated to 80%, and "* 3" is effective. Concentrated to 50% of the component and used. Moreover, the numerical value in a table | surface shows "mass%."

The meanings of the abbreviations in the table are as follows.
PE-10: dimethylamine * polyalkylenepolyamine * epichlorohydrin (Yokkaichi Gosei Co., Ltd., active ingredient 51%)
G5615: polydiallyldimethylammonium chloride (Daiichi Kogyo Seiyaku, 48% active ingredient)
PAS-A-1: diallyldimethylammonium chloride * sulfur dioxide copolymer (manufactured by Nittobo, 40% active ingredient)
PS-350: acrylamide * [2- (acryloyloxy) ethyl] trimethylammonium chloride (manufactured by Hymo, active ingredient 20%)
-KPV100LU: Polyacrylic acid ester (manufactured by Senka, 26% active ingredient)
PAA-03: polyallylamine (Nittobo, active ingredient 15%)
Lami Bruf A-1: potassium p-tert-butylbenzoate (Daiichi Kogyo Seiyaku Co., Ltd., active ingredient 40%)

The ink used for image formation was prepared as follows.
[Preparation Example 1]
The materials having the following formulation were mixed and stirred to obtain an ink.
-Cyan dispersion (PAC205, manufactured by Kao Corporation) 20.0%
・ 1,3-butanediol 23.0%
・ Glycerin 8.0%
・ 2-ethyl-1,3-hexanediol 2.0%
・ Zonyl FS-300 (manufactured by DuPont, fluorinated surfactant) 1.0%
・ Proxel LV (Avecia) 0.2%
2-amino-2-ethyl-1,3-propanediol 0.3%
・ Ion exchange water 45.5%

[Preparation Example 2]
The materials having the following formulation were mixed and stirred to obtain an ink.
・ Yellow dispersion (PAY204, manufactured by Kao Corporation) 20.0%
・ 1,6-hexanediol 24.5%
・ Glycerin 8.0%
・ 2-ethyl-1,3-hexanediol 2.0%
・ Zonyl FS-300 (DuPont, fluorosurfactant) 0.5%
・ Proxel LV (Avecia) 0.2%
2-amino-2-ethyl-1,3-propanediol 0.3%
・ Ion exchange water 44.5%

Corrosivity and beading were evaluated as follows using the treatment liquids of the above Examples and Comparative Examples and the inks of Preparation Examples 1 and 2. The results are summarized in Tables 4 to 6.

<Corrosive>
28.3 g of each of the treatment liquids of Examples and Comparative Examples were weighed out into a glass bottle with a capacity of 30 cc, and general stainless steel SUS304 pellets (φ = 12 mm, d = 4 mm) were put therein.
Next, after standing at 50 ° C. for 3 weeks, the SUS304 pellets were taken out, and the corrosion of the treatment liquid and the surface of the SUS304 pellets was visually observed and evaluated according to the following criteria.
In addition, the pellet was wiped with water, ethanol and air before removing the impurities on the surface of the pellet before being put into the treatment liquid.

(Evaluation criteria)
A: Corrosion does not occur.
○: Slight corrosion is observed but there is no practical problem.
X: Corrosion is clearly recognized and considered to be a problem in practical use.

<Beading>
(1) Each of the treatment liquids of Examples and Comparative Examples is applied to the surface of the coating layer of a recording medium having a coating layer (STORA ENSO, Lumiart gloss paper, paper thickness 90 g / m ² ) by a roller coating method. .9 ± 0.2 g / m ^{2 was} deposited.
(2) The recording medium to which the treatment liquid was attached was placed in a 90 ° C. constant temperature bath for 30 seconds, and the treatment liquid attached to the recording medium was dried.
(3) Ink in which pigment particles having a negative charge are dispersed by the water-based inkjet recording method with respect to each of the recording medium (1) (without drying) and the recording medium (2) (with drying). Was discharged at a single pass of 600 dpi (120 m / min) to form an image, and then the degree of beading was visually observed and evaluated according to the following criteria.
As the ink, green ink of Preparation Example 1 (Cyan): Preparation Example (Yellow) = 1.15: 1.00 (mass ratio) was used, and the adhesion amount was 3.2 × 10 ⁻⁸ g / cm ² .

(Evaluation criteria)
A: No beading is observed.
○: Slight beading is observed when the eyes are closely examined, but there is no problem in image quality.
(Triangle | delta): Beading can be confirmed and there exists a problem on image quality.
X: The beading is clearly conspicuous.

<Corrosive (polarization curve)>
Since the <corrosion> evaluation in paragraph 0066 is performed under severe conditions, it can be said that there is no practical problem if no corrosion is observed by visual evaluation.
However, in order to investigate the superiority or inferiority of the corrosivity of the treatment liquid, a more detailed evaluation is necessary.
Therefore, the superiority or inferiority of the corrosivity was judged by obtaining the dissolved oxygen current density correlated with the corrosion rate from the polarization curve obtained by the electrochemical measurement method.
As the electrochemical measurement unit, SI1280B (manufactured by Solartron) was used, and the working electrode was fixed with a crocodile clip so that the SUS304 sheet metal was immersed in the treatment solution by 1.00 cm ² , and the counter electrode was Pt wire (VC -2 Pt counter electrode (manufactured by BAS), and a reference electrode was an Ag / AgCl standard electrode [RE-1B, aqueous reference electrode (Ag / AgCl): manufactured by BAS].
As measurement conditions, the potential was varied from the initial potential (natural potential) to 1.5 V, the oxidation polarization curve was measured, the working electrode sample and the treatment solution were replaced with new ones, and then the initial potential (natural potential) was further measured. The reductive polarization curve was measured by changing the potential from −1.5V to −1.5V.
Then, the value of the dissolved oxygen diffusion limit current density I (A / cm ² ) was ranked according to the following evaluation criteria. The smaller the value, the slower the corrosion rate.
(Evaluation criteria)
A: I <3.00 × 10 ⁻⁶
B: 3.00 × 10 ⁻⁶ ≦ I <5.00 × 10 ⁻⁶
C: 5.00 × 10 ⁻⁶ ≦ I

The following can be understood from the results of Tables 4 to 6 above.
-The processing liquid of an Example is excellent in corrosivity, and the image excellent also in the point of beading is obtained.
-The treatment solution of the example to which citrate was added is more corrosive than the case of not adding it.
Comparative Example 1 is an example in which the addition amount of the cationic polymer according to the present invention is less than 40%, and there is a problem with beading.
Comparative Examples 2 to 3 are examples containing an appropriate amount of the cationic polymer according to the present invention but not containing a phosphoric acid-based inorganic salt or p-tert-butylbenzoate, and have a problem with corrosivity.
Comparative Examples 4 to 5 are examples using other cationic polymers, and there is no problem with corrosion even if the rust preventive agent is not included, but there is a problem with beading.
Comparative Example 6 is an example using a flocculant other than a cationic polymer, and there is no problem with beading without corrosiveness and drying, but there is a problem with beading when the recording medium is dried after applying the treatment liquid. .

201 Counter roller 203 Recording medium 204 Pretreatment liquid coating device 205 Pretreatment liquid 206 Stirring / supply roller 207a Transfer / thinning roller 207b Transfer / thinning roller 208 Coating roller 209 Pressure adjustment device 300 Inkjet recording device 301 Recording medium transport unit 302 Pre-processing section 303 Pre-processing and post-drying section 304 Image forming section 304K Black recording head 304K-1 Black head unit 304K-2 Black head unit 304K-3 Black head unit 304K-4 Black head unit 304C Cyan Recording head 304M Magenta recording head 304Y Yellow recording head 305 Post-processing section 306 Drying process 307 Paper feeding device 308 Winding device 309 Nozzle surface 310 Printing nozzle 11 a heat roller 312 heat roller 313 heat roller 314 heat roller 315 before drying unit

JP 07-268665 A Japanese Patent No. 4254235 JP 2009-137052 A JP 2012-040778 A JP 2013-163370 A

Claims (9)

A processing liquid applied before applying ink to a recording medium, wherein the processing liquid satisfies the following requirements [1] to [3].
[1] A water-soluble cationic polymer having a quaternary ammonium cation in the main chain and a chlorine ion as a counter ion (counter ion) , a phosphoric acid-based inorganic salt or p-tert-butylbenzoate, water Containing.
[2] The phosphoric acid-based inorganic salt is any of sodium monohydrogen phosphate, sodium dihydrogen phosphate, sodium polyphosphate, potassium monohydrogen phosphate, and potassium dihydrogen phosphate.
[3] Contains 40 to 60% by mass of the cationic polymer.   The treatment liquid according to claim 1, further comprising citrate.   The treatment liquid according to claim 1, wherein the phosphoric acid-based inorganic salt contains at least sodium monohydrogen phosphate.   The treatment liquid according to claim 1, wherein the p-tert-butyl benzoate includes a sodium salt or a potassium salt. The treatment liquid according to claim 1, wherein the cationic polymer has a repeating unit represented by the following general formula (1).
<General formula (1)>

In the above formula, R1 and R2 may be the same or different and each represents an alkyl group, a hydroxyalkyl group, an alkenyl group, or a benzyl group having 1 to 8 carbon atoms.   A treatment liquid applying step for applying the treatment liquid according to any one of claims 1 to 5 to a recording medium, and image formation for forming an image by ejecting aqueous ink onto the recording medium to which the treatment liquid has been applied by an inkjet method. An image forming method comprising a step.   The image forming method according to claim 6, wherein the recording medium has a coating layer on at least one surface of the support.   A recorded matter, wherein an image is recorded by the image forming method according to claim 6.   A processing liquid applying means for applying the processing liquid according to any one of claims 1 to 5 to a recording medium, and image formation for forming an image by ejecting aqueous ink onto the recording medium to which the processing liquid has been applied by an ink jet method. An ink jet recording apparatus comprising: means.

Images