JP2018058936A - Method for improving scratch resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for improving various scratch resistance, particularly wet scratch resistance.SOLUTION: The present invention provides a method for improving scratch resistance using an ink containing a quinacridone pigment and an azo pigment as colorants and further containing a polymer, a wax, and water, wherein monomers constituting the polymer comprise at least one monomer selected from methacrylic acid derivatives and at least one monomer selected from acrylic acid derivatives.SELECTED DRAWING: None

Description

  The present invention relates to a method for improving scratch resistance.

Ink-jet inks contain two colorants: water-soluble colorants (such as acid dyes and direct dyes) and water-insoluble or sparingly soluble colorants (such as disperse dyes, solvent dyes, and pigments). Can be separated. Among these, since various fastnesses are excellent, in recent years, an ink (pigment ink) containing a colorant that is insoluble or hardly soluble in water, particularly a pigment, is mainly used for industrial applications.
In the ink jet recording method, various recording media are used. As one of them, there is an ink jet dedicated paper (glossy paper) having an ink receiving layer. On the other hand, plain paper and non-hardly absorbable recording media with low ink absorption capability are often used. These recording media do not have an ink receiving layer. For this reason, when recording with water-based ink on these recording media, the problem is that the scratch resistance of the recorded image is weakened. In particular, when recording is performed with water-based pigment ink, the ink may easily transfer or peel off due to friction.
In industrial applications, images recorded with ink are often used outdoors. When this recorded image is used outdoors, there may be a large difference in scratching of the recorded image between clear weather and rainy weather, which is a problem. That is, it is recognized that the scratching of the recorded image under rainy weather is greatly deteriorated under fine weather, which is a problem.
For this reason, there is a strong demand for a method for improving the scratch resistance under wet conditions corresponding to rainy weather as well as dry conditions corresponding to fine weather.

Patent Documents 1 and 2 disclose inks that have good scuffing properties and high-quality images by controlling the permeability to paper with a surfactant and a penetrating agent.
Patent Documents 3 and 4 disclose a technique for improving the friction resistance by adding a resin to the ink so as to provide adhesion to a recording medium.
Patent Document 5 discloses an ink composition containing a polymer, and Patent Document 6 discloses a wax containing a wax.

International Publication No. 2008/105289 JP 2003-253167 A JP 2013-166844 A JP 2013-199605 A International Publication No. 2015/152291 International Publication No. 2015/147192

  An object of the present invention is to provide a method for improving various scratch properties, particularly wet scratch properties.

As a result of intensive studies to solve the above problems, the present inventors have solved the above problems by using an ink containing a quinacridone pigment and an azo pigment as colorants, and further containing a polymer, a wax, and water. The present invention has been completed by finding out what can be done. That is, the present invention relates to the following 1) to 6).
1)
A method for improving the scratching property using an ink containing a quinacridone pigment and an azo pigment as a colorant and further containing a polymer, a wax, and water.
However, the monomer constituting the polymer contains a monomer selected from at least one of a methacrylic acid derivative and an acrylic acid derivative.
2)
The method according to 1) above, wherein the wax contains at least one selected from polyethylene wax, polypropylene wax, oxidized polyethylene wax, oxidized polypropylene wax and paraffin wax.
3)
The quinacridone pigment is C.I. I. Pigment red 122, 202, and C.I. I. The method for improving scratch resistance according to 1) above, which is a pigment selected from CI Pigment Violet 19.
4)
The method according to 1) above, wherein the monomers constituting the polymer are three types of monomers selected from methacrylic acid derivatives and one type of monomers selected from acrylic acid derivatives.
5)
The method according to 1) or 4) above, wherein the monomers constituting the polymer are two kinds of alkyl methacrylate, methacrylic acid, and alkyl acrylate.
6)
The azo pigment is C.I. I. The method for improving scratch resistance according to 1) above, which is CI Pigment Red 150.

  According to the present invention, various methods for improving scratch resistance, particularly wet scratch resistance, can be provided.

Hereinafter, the ink of the present invention will be described in detail.
In this specification, “CI” is an abbreviation for color index.
Further, in the present specification, “%” and “part” are described on a mass basis unless otherwise specified, including examples.

[Quinacridone pigment]
Examples of the quinacridone pigment include C.I. I. Pigment red and C.I. I. And quinacridone pigments selected from pigment violet. Such quinacridone pigments can be easily searched, for example, from the search screen of Color Index International available online. Among them, C.I. I. Pigment red 122, 202 and C.I. I. Pigment violet 19 is preferred, C.I. I. Pigment red 122 and C.I. I. A pigment selected from Pigment Violet 19 is more preferred. In the following description, “CI pigment red” is referred to as “PR”, and “CI pigment violet” is referred to as “PV”.

[Azo pigment]
Examples of the azo pigment include C.I. I. And azo pigments selected from CI Pigment Red. Such azo pigments can be easily searched from, for example, a search screen of Color Index International available online. Among them, PR150 is preferable.

  The total content of the colorant contained in the ink is usually 0.5% to 10%, preferably 0.5% to 8%, more preferably 1% to 8%, and further preferably 2% to 7%. . When the content is 0.5% or more, sufficient color developability of the recorded image is obtained, and when it is 10% or less, the discharge property is good.

  The content ratio of the quinacridone pigment and the azo pigment relative to the total mass of the colorant is usually 95/5 to 5/95, preferably 90/10 to 10/90, more preferably 80/20 to 20/80, and even more preferably 70. / 30 to 30/70. By setting such a ratio, a recorded image with a good balance between color development and saturation can be obtained.

[polymer]
The monomer constituting the polymer is preferably a monomer selected from at least one of each of a methacrylic acid derivative and an acrylic acid derivative;
3 types of monomers selected from methacrylic acid derivatives and 1 type of monomer selected from acrylic acid derivatives are more preferred;
Two types of alkyl methacrylate, methacrylic acid, and alkyl acrylate are more preferred.
The two types of alkyl methacrylate constituting the polymer are preferably monomers selected from linear alkyl methacrylate and unsaturated alkyl methacrylate.
Of the foregoing, the straight chain alkyl methacrylate is more preferably a straight chain C1-C3 alkyl methacrylate, and more preferably methyl methacrylate.
Of the above, the unsaturated alkyl methacrylate is more preferably an unsaturated C1-C4 alkyl methacrylate, and more preferably allyl methacrylate.
In addition, the alkyl acrylate constituting the polymer is preferably a branched alkyl acrylate, more preferably a branched C1-C8 alkyl acrylate, and even more preferably 2-ethylhexyl acrylate.
The polymer can be obtained, for example, by a synthetic method disclosed in International Publication No. 2015/147192 Gazette. The third polymer can also be used as an emulsion.

The average particle size of the polymer is usually 10 nm to 1 μm, preferably 30 nm to 500 nm. At such an average particle size, the ink jet head is not easily clogged or produced.
The glass transition point (Tg) of the polymer is usually −10 ° C. to 20 ° C., preferably −5 ° C. to 15 ° C.
The acid value of the polymer is usually 0 to 25 mg KOH / g, preferably 5 to 15 mg KOH / g.
The insolubility of the polymer in tetrahydrofuran is usually 80 to 100%, preferably 100%, that is, insoluble. Thereby, the average molecular weight of the resin can be controlled, and a resin containing no free monomer can be obtained.
The polymer content with respect to the total mass of the ink is usually 0.1% to 10%, preferably 0.2% to 8%, more preferably 0.3% to 8%. When the content is such, the scuffing property, the redispersibility, and the discharge property are good.

The monomer composition of the polymer is summarized in Table 1 below as “normal”, “preferred”, and “more preferable” configurations. In the range of each monomer shown in Table 1 below, the total amount of monomers can be 100 parts. The abbreviations in Table 1 below have the following meanings.
MA: Methacrylic acid.
ScMA: linear alkyl methacrylate.
BcAA: branched chain alkyl acrylate.
UsMA: unsaturated alkyl methacrylate.

[wax]
The wax contained in the ink is preferably a wax emulsion, and more preferably an aqueous wax emulsion. Natural wax and chemically synthesized wax can be used as the wax.
Natural waxes include petroleum waxes such as paraffin wax and microcrystalline wax, lignite waxes such as montan wax, plant waxes such as carnauba wax and canderia wax, beeswax and lanolin as animal and plant waxes, etc. And an emulsion in which is dispersed in an aqueous medium.

  As the wax emulsion, at least one wax selected from polyethylene wax, polypropylene wax, oxidized polyethylene wax, oxidized polypropylene wax and paraffin wax, or a mixed wax thereof is preferably dispersed in an aqueous medium. An emulsion is mentioned.

  Further, the particle size of the wax emulsion is preferably 5 μm or less, and more preferably 1 μm or less in order to prevent clogging of the inkjet head.

Examples of products that are commercially available as wax emulsions include, for example, CERAFLOUR 925, 929, 950, 991, AQUACER 498, 515, 526, 531, 537, 539, 552, 1547, AQUAMAT 208, 263, 272, manufactured by Big Chemie. MINEPOL221, etc .; Mitsui High Wax NL100, NL200, NL500, 4202E, 1105A, 2203A, NP550, NP055, NP505, etc. manufactured by Mitsui Chemicals; KUE-100, 11 manufactured by Sanyo Chemical
Of these, AQUACER 515, 531, 537, 539, 1547 is preferred; AQUACER 515, 531, 537, 1547 is more preferred.

  The wax content relative to the total mass of the ink is usually 0.1% to 10%, preferably 0.2% to 8%, more preferably 0.3% to 8%. When the content is such, the scuffing property, the redispersibility, and the discharge property are improved.

  The content ratio of the polymer and the wax in the total mass of the polymer and the wax contained in the ink is usually 95/5 to 5/95, preferably 90/10 to 10/90, more preferably 80/20 to 20 /. 80. By setting such a ratio, a recorded image having a good balance between redispersibility and fixability can be obtained.

  The ink can be used as a magenta ink. For the purpose of obtaining a full-color recorded image, it can be used as an ink set including, for example, cyan ink, yellow ink, and black ink. At this time, the colorant contained in each ink of cyan, yellow, and black is not particularly limited, and a known pigment can be arbitrarily used. In addition to the ink set of four colors, for the purpose of obtaining a recorded image of a higher definition hue, for example, an ink set of four or more colors, each of which is optionally added with inks of violet, orange to brown, green, etc. You can also

[Dispersant]
The ink may contain a dispersant. Also, a part or all of the pigment can be coated with a dispersant.
Examples of the dispersant include nonionic dispersants, anionic dispersants, and polymer dispersants, which can be appropriately selected according to the purpose. Among these, at least one selected from the group consisting of a nonionic dispersant, an anionic dispersant, and a polymer dispersant is preferable.
The amount of the dispersant used is usually 1 to 100%, preferably 5 to 90%, more preferably 10 to 80% with respect to the total mass of the pigment as a mass ratio in terms of solid content when preparing the dispersion. %. By setting it as such usage-amount, a pigment can fully be refined | miniaturized. In addition, it is possible to suppress bleeding of an image recorded with the ink containing this dispersion and to obtain good water resistance and scratch resistance.

  Nonionic dispersants include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyalkylene glycol, glycerin ester, sorbitan ester, sucrose ester, glycerin ester polyoxyalkylene ether, sorbitan ester polyoxyalkylene ether, Sorbitol ester polyoxyalkylene ether, fatty acid alkanolamide, polyoxyalkylene fatty acid amide, amine oxide, polyoxyalkylene alkylamine, polyoxyalkylene-β-naphthyl ether, polyoxyalkylene styryl phenyl ether, polyoxyalkylene distyryl phenyl ether Etc.

  Anionic dispersants include alkyl sulfates, alkyl ether sulfates, alkyl ester sulfates, alkyl aryl ether sulfates, alkyl sulfonates, sulfosuccinates, alkyl aryl and alkyl naphthalene sulfonates, alkyl phosphates, Examples include polyoxyalkylene alkyl ether phosphate ester salts, alkyl allyl ether phosphate salts, polyoxyalkylene alkyl ether sulfate salts, polyoxyalkylene styryl phenyl ether sulfate salts, and polyoxyalkylene distyryl phenyl ether sulfate salts.

Examples of the polymer dispersant include styrene and derivatives thereof; vinyl naphthalene and derivatives thereof; aliphatic alcohol esters of α, β-ethylenically unsaturated carboxylic acids and the like; acrylic acid and derivatives thereof; maleic acid and derivatives thereof; Its derivatives; fumaric acid and its derivatives; at least two monomers selected from the group consisting of vinyl acetate, vinyl alcohol, vinyl pyrrolidone, acrylamide, and derivatives thereof (preferably at least one of these monomers) For example, a block copolymer, a random copolymer and a graft copolymer, and / or a salt thereof.
The weight average molecular weight of the dispersant is about 1,000 to 60,000, preferably 2,000 to 50,000, more preferably about 2,500 to 50,000. Moreover, an acid value is about 10-300 as mgKOH / g, Preferably it is 10-275, More preferably, it is about 20-250.
Specific examples of the commercially available products include, for example, Joncrill 61J, 67, 68, 450, 55, 555, 586, 678, 680, 682, 683, 690, and B-36 manufactured by BASF. .

As a method for preparing an aqueous dispersion containing a colorant, all known methods can be used. For example, a known method of mixing a colorant and a dispersant and performing a dispersion treatment using a sand mill (also referred to as a bead mill), a roll mill, a ball mill, a paint shaker, an ultrasonic disperser, a microfluidizer, or the like. . Among these, a sand mill (bead mill) is preferable. For the preparation of the dispersion using a sand mill, it is preferable to use a bead having a diameter of about 0.01 mm to 1 mm and to increase the filling rate of the bead to prepare the dispersion under conditions that increase the dispersion efficiency.
After preparation of the dispersion, it is also preferable to remove beads and the like by filtration and / or centrifugation and to remove particle components having a large deviation from the target average particle diameter.
When foaming occurs during the preparation of the dispersion, a very small amount of a known antifoaming agent such as silicone or acetylene glycol can be added.
Other methods include acid precipitation method, phase inversion emulsification method, interfacial polymerization method, in-situ polymerization method, submerged cured coating method, coacervation (phase separation) method, submerged drying method, melt dispersion cooling method, Examples thereof include an air suspension coating method and a spray drying method. Among these, a phase inversion emulsification method, an acid precipitation method and an interfacial polymerization method are preferable.

  Instead of using the above-mentioned dispersant, a surface-treated pigment (self-dispersed pigment) in which a dispersibility-imparting group is chemically introduced on the surface of the colorant can also be used as the colorant.

The average particle diameter (D50) of the colorant in the dispersion is usually 300 nm or less, preferably 30 to 280 nm, more preferably 40 to 270 nm, and still more preferably 50 to 250 nm.
Similarly, D90 is usually 300 nm or less, preferably 280 nm or less, more preferably 270 nm or less. The lower limit is preferably 100 nm or more.
Similarly, D10 is usually 10 nm or more, preferably 20 nm or more, more preferably 30 nm or more, and the upper limit is 100 nm or less.

  The water is preferably water having a pH of 6.5 to 7.5, such as distilled water, ion exchange water, pure water, or ultrapure water, and low free ion content such as various metal ions.

  The ink is composed of a water-soluble organic solvent, a binder, a water-soluble polymer compound, a surfactant, a fungicide, a preservative, a pH adjuster, a chelating reagent, a rust inhibitor, a water-soluble UV absorber, An ink preparation agent such as an antioxidant can be contained as required. One type of ink preparation agent can be used, or two or more types can be used in combination.

[Water-soluble organic solvent]
The water-soluble organic solvent contained in the ink is not particularly limited. For example, C1-C6 alkanol such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol or tert-butanol; N, N-dimethyl Carboxylic acid amides such as formamide or N, N-dimethylacetamide; lactams such as 2-pyrrolidone, N-methyl-2-pyrrolidone or N-methylpyrrolidin-2-one; 1,3-dimethylimidazolidin-2-one or Cyclic ureas such as 1,3-dimethylhexahydropyrimido-2-one; ketones or ketoalcohols such as acetone, 2-methyl-2-hydroxypentan-4-one, ethylene carbonate; cyclics such as tetrahydrofuran and dioxane Ether; ethylene glycol, Ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, polyethylene glycol (preferably Having a molecular weight of 400, 800, 1540 or higher), mono-, oligo- or polyalkylene glycols or thioglycols having C2-C6 alkylene units such as polypropylene glycol, thiodiglycol or dithiodiglycol; glycerin, diglycerin, hexane- C3-C9 polyols (triols) such as 1,2,6-triol and trimethylolpropane; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethyl Glycol monoallyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol), triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, propylene Glycol ethers such as glycol monopropyl ether, prolene glycol monobutyl ether, dipropylene glycol monomethyl ether (preferably from C3-C10 mono-, di- or triethylene glycol ether, and C4-C13 mono-, di- or tripropylene glycol ether) Glycol ether selected from the group consisting of 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3- C5-C9 alkanediols such as hexanediol and 2,4-diethyl-1,5-pentanediol; γ-butyrolactone, dimethyl sulfoxide, and the like.
The total content of the water-soluble organic solvent with respect to the total mass of the ink is usually 0% to 60%, preferably 5% to 60%, more preferably 10% to 50%.

[binder]
Examples of the binder include urethane-based, polyester-based, acrylic-based, vinyl acetate-based, vinyl chloride-based, acrylic styrene-based, acrylic silicone-based, and styrene-butadiene-based resins or emulsions containing the same. Among these, resins selected from urethane, acrylic, and styrene butadiene are preferable.
Specific examples of commercially available products include, for example, Superflex 126, 130, 150, 170, 210, 420, 470, 820, 830, 890 (urethane resin emulsion manufactured by Daiichi Kogyo Seiyaku Co., Ltd.); Hydran HW-350 , HW-178, HW-163, HW-171, AP-20, AP-30, WLS-201, WLS-210 (urethane resin emulsion manufactured by DIC Corporation); 0569, 0850Z, 2108 (manufactured by JSR Corporation) Styrene-butadiene resin emulsion); AE980, AE981A, AE982, AE986B, AE104 (acrylic resin emulsion manufactured by Etec Co., Ltd.) and the like.

[Water-soluble polymer]
Examples of the water-soluble polymer compound include anionic and nonionic polymer compounds. Examples of the anionic polymer compound include cellulose derivatives such as carboxymethyl cellulose, acrylic acid derivatives such as polyacrylic acid, and polystyrene derivatives such as polystyrene sulfonate. Examples of nonionic polymer compounds include polyethylene glycol, polyvinyl alcohol, polyvinyl pyrrolidone, and gelatin.

[Surfactant]
Examples of the surfactant include anionic, cationic, nonionic, amphoteric, silicone-based, and fluorine-based surfactants. Among these, at least one surfactant selected from the group consisting of an anionic surfactant and a nonionic surfactant is preferable.
When the ink contains a surfactant, the total content of the surfactant with respect to the total mass of the ink is usually 0.1% to 3%, preferably 0.2% to 2.5%. If it is 0.1% or more, the effect as a surfactant is obtained, and if it is 3% or less, the dispersion stability of the pigment becomes good.

  Anionic surfactants include alkyl sulfocarboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, polyoxyethylene alkyl ether sulfates, polyoxyethylene dinonyl phenyl ether sulfates, polyoxyethylene lauryl ethers. Sulfate, N-acyl amino acid or salt thereof, N-acylmethyl taurate, alkyl sulfate polyoxyalkyl ether sulfate, alkyl sulfate polyoxyethylene alkyl ether phosphate, rosin acid soap, castor oil sulfate ester, lauryl Alcohol sulfates, alkylphenol phosphates, alkyl phosphates, alkylaryl sulfonates, diethyl sulfonates, diethyl hexyl sulfonates, dioctyl sulfonates, etc. It is. Specific examples of commercially available products include, for example, Hightenol LA-10, LA-12, LA-16, NE-05, NE-15, NF-13, NF-17, Neohightenol ECL-30S, ECL-45. (Daiichi Kogyo Seiyaku Co., Ltd.), Adeka Coal EC-8600 (Adeka Co., Ltd.), Perex OT-P (Kao Co., Ltd.) and the like.

  Examples of the cationic surfactant include 2-vinylpyridine derivatives and poly-4-vinylpyridine derivatives.

  Examples of amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyldimethylaminoacetic acid betaine, polyoctylpolyaminoethylglycine, and imidazoline derivatives. Can be mentioned.

  Nonionic surfactants include polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether, and other ethers ( For example, Softanol EP-5035, 7085, 9050 manufactured by Nippon Shokubai Co., Ltd .; Pluronic L-31, L-34, L-44 manufactured by Adeka Co., Ltd.); polyoxyethylene oleate, polyoxyethylene distearate , Sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate, polyoxyethylene stearate Ester systems such as 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1- Acetylene glycol (alcohol) system such as hexyn-3-ol; polyoxyethylene acetylene glycol ether; polyoxyethylene distyrenated phenyl ether; polyoxyethylene tribenzylated phenyl ether; Surfynol 104 manufactured by Nisshin Chemical Co., Ltd. 104PG50, 105PG50, 82, 420, 440, 465, 485; Orphine STG; Polyglycol ether type (for example, TegItol15-S-7 manufactured by SIGMA-ALDRICH) and the like.

  Examples of the silicone surfactant include polyether-modified siloxane and polyether-modified polydimethylsiloxane. Specific examples of commercially available products include BYK-347 (polyether-modified siloxane); BYK-345, BYK-348, BYK-349 (polyether-modified polydimethylsiloxane) manufactured by BYK Chemie.

  Examples of the fluorosurfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate ester compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group as a side chain. And polyoxyalkylene ether polymer compounds. Specific examples of commercially available products include, for example, Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, Capstone FS-30, FS-31 (manufactured by DuPont); PF-151N, PF -154N (manufactured by Omninova);

[Antidepressant]
Specific examples of the antifungal agent include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, p-hydroxybenzoic acid ethyl ester, 1,2-benzisothiazolin-3-one, and salts thereof. .

[Preservative]
Examples of preservatives include, for example, organic sulfur, organic nitrogen sulfur, organic halogen, haloaryl sulfone, iodopropargyl, haloalkylthio, nitrile, pyridine, 8-oxyquinoline, benzothiazole , Isothiazoline, dithiol, pyridine oxide, nitropropane, organotin, phenol, quaternary ammonium salt, triazine, thiazine, anilide, adamantane, dithiocarbamate, brominated indanone, benzyl Examples thereof include bromoacetate-based or inorganic salt-based compounds.
Specific examples of the organic halogen compound include, for example, sodium pentachlorophenol.
Specific examples of the pyridine oxide compound include sodium 2-pyridinethiol-1-oxide.
Examples of isothiazoline compounds include 1,2-benzisothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 5- Chloro-2-methyl-4-isothiazolin-3-one magnesium chloride, 5-chloro-2-methyl-4-isothiazolin-3-one calcium chloride, 2-methyl-4-isothiazolin-3-one calcium chloride and the like It is done.
Specific examples of other antiseptic / antifungal agents include anhydrous sodium acetate, sodium sorbate, sodium benzoate, trade names Proxel GXL (S), Proxel LV, Proxel XL-2 (S) manufactured by Arch Chemical Co., Ltd. .

[PH adjuster]
Specific examples of the pH adjusting agent include alkanolamines such as diethanolamine, triethanolamine and N-methyldiethanolamine; hydroxides of alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide; ammonium hydroxide (ammonia Water); alkali metal carbonates such as lithium carbonate, sodium carbonate, sodium bicarbonate, potassium carbonate; alkali metal salts of organic acids such as sodium silicate and potassium acetate; and phosphates such as disodium phosphate Is mentioned.

[Chelating reagent]
Specific examples of the chelating reagent include, for example, disodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, and sodium uracil diacetate.

[Rust preventive]
Specific examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.

[Water-soluble UV absorber]
Examples of water-soluble ultraviolet absorbers include sulfonated benzophenone compounds, benzotriazole compounds, salicylic acid compounds, cinnamic acid compounds, and triazine compounds.

[Antioxidant]
As examples of the antioxidant, for example, various organic and metal complex anti-fading agents can be used. Examples of the organic anti-fading agent include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, and heterocyclic rings. It is done.

[Defoamer]
Examples of the antifoaming agent include silicone-based, silica mineral oil-based, olefin-based, and acetylene-based. Examples of commercially available antifoaming agents include Surfinol DF37, DF58, DF110D, DF220, MD-20, and Olfin SK-14, all manufactured by Shin-Etsu Chemical Co., Ltd.
When using an antifoamer, the addition amount is 0.01 to 5% normally, Preferably it is 0.03 to 3%, More preferably, it is 0.05 to 1%. When it is 0.01% or more, an effect as an antifoaming agent is obtained, and when it is 5% or less, the dispersion stability is good.

When the ink is used as an ink for ink jet recording, it is preferable to use an ink containing a small amount of inorganic impurities such as metal cation chloride (for example, sodium chloride) and sulfate (for example, sodium sulfate). preferable. The standard of the content of the inorganic impurities is about 1% or less with respect to the total mass of the colorant, and the lower limit includes the detection limit of the analytical instrument, that is, 0%.
Inorganic impurities are often mixed in the colorant. For this reason, an inorganic impurity can be removed as needed. As a purification method, for example, a method of suspending and purifying a solid of a colorant with a mixed solvent of (C1-C4) alcohol such as methanol and water, or the like; or after preparing an ink, inorganic impurities are removed with an ion exchange resin. Examples include a method of exchange adsorption.

The pH of the ink is usually preferably 7 to 11 or 8 to 10.
The surface tension of the ink is usually preferably 10 to 50 mN / m and 20 to 40 mN / m.
The viscosity of the ink is usually preferably 2 mPa · s to 30 mPa · s, 3 mPa · s to 20 mPa · s.
The pH and surface tension of the ink can be appropriately adjusted with a pH adjuster, a surfactant, a water-soluble organic solvent, or the like.

  The ink can be used in various recordings. For example, it is suitable for writing instruments, water-based printing, information recording, textile printing, etc., and particularly preferably used for ink jet recording.

The ink jet recording method is a method of recording by ejecting the ink droplets according to a recording signal and attaching them to a recording medium. There is no restriction | limiting in particular about the ink nozzle of an inkjet printer, an inkjet system, etc., It can select suitably according to the objective.
When recording by the inkjet recording method, a container containing the ink is loaded at a predetermined position of the inkjet printer, and recording is performed on a recording medium by the recording method.

As the ink jet method, a known method can be used. Specific examples of the ink jet method include a charge control method, a drop-on-demand (pressure pulse) method, an acoustic ink jet method, a thermal ink jet method, and the like.
In addition, a method of improving the image quality by ejecting a large amount of ink with a small colorant content in the ink in a small volume; using a plurality of inks having substantially the same hue and different concentrations of the colorant in the ink And a method for improving the fixing property of the colorant by using a colorless and transparent ink.

The recording medium means a substance to which the ink can adhere. Examples of the recording medium include, for example, sheet-like materials such as paper and film; fibers and cloth (cellulose, nylon, wool, etc.); leathers; base materials for color filters. The recording medium to which the ink is attached is included in the scope of the present invention.
Recording media can be broadly classified into those having an ink receiving layer and those having no ink receiving layer.
The ink receiving layer can be applied to the recording medium by a known method. It is also possible to purchase a recording medium that already has an ink receiving layer. Typical examples of the recording medium having an ink receiving layer include sheet-like recording media generally referred to as ink jet exclusive paper, ink jet exclusive film, glossy paper, and the like. Typical examples include professional photo paper manufactured by Canon Inc., super photo paper, glossy gold and matte photo paper; photo paper Krispia (high gloss), photo paper (gloss), photo matte manufactured by Seiko Epson Corporation. Paper: Advanced Photo Paper (Glossy) manufactured by Hewlett-Packard Japan, Inc., and Photographic Finishing Pro Pro manufactured by Fuji Film Co., Ltd.

Examples of the recording medium having no ink receiving layer include various papers such as coated paper and art paper used for gravure printing, offset printing, and cast coated paper used for label printing.
When using a recording medium that does not have an ink receiving layer, it is also preferable to subject the recording medium to a surface modification treatment for the purpose of improving the fixability of the colorant.

As the surface modification treatment, it is preferable to perform at least one treatment selected from corona discharge treatment, plasma treatment and flame treatment. As these treatments, known methods can be used. In addition, it is generally known that the effects of these treatments decrease with time. For this reason, when surface modification processing is performed on the information transmission sheet, it is preferable to continuously perform ink jet recording without taking time.
The surface modification treatment can be performed by appropriately adjusting the number of treatments, time, applied voltage, and the like so as to obtain a desired effect.

According to the present invention, an ink having various scratch properties, particularly excellent scratch properties and good color developability even in a wet state as in a dry state was obtained. Further, the ink of the present invention is excellent in redispersibility and marker resistance, and has good chroma.
Furthermore, an image recorded with the ink of the present invention is excellent in various fastness properties such as water resistance, light resistance, heat resistance, and oxidation gas resistance (for example, ozone gas resistance).

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by a following example.
The pigment solid content in the dispersion was determined by dry weight method using MS-70 manufactured by A & D Corporation. The average particle diameter of the pigment in the dispersion solution was determined using Nanotrac Wave-EX150 manufactured by Microtrac Bell.

[Preparation Example 1] Preparation of an aqueous solution of a dispersant.
Joncryl 678 (20 parts) and triethanolamine (11.4 parts) were added to ion-exchanged water (68.6 parts) and stirred for 1 hour to obtain an aqueous solution of a dispersant. “Joncrill 678” in Table 2 below means this aqueous solution.

[Preparation Example 2]: Preparation of dispersions 1 to 4.
Each component described in Table 2 below was mixed, and dispersion treatment was performed for 15 hours under a condition of 1500 rpm with a sand grinder to obtain a liquid. After 100 parts of ion-exchanged water was dropped into the obtained liquid, dispersion beads 1 to 4 were obtained by filtering and separating the dispersion beads from this liquid.
In Tables 2 and 3 below, the numerical values indicating the amounts of the components are all “parts”, and “-” indicates that the components are not included. In addition, “water” used ion-exchanged water. “Olfin SK-14” is an antifoaming agent. This component is removed at the same time as the dispersion beads are separated by filtration in the preparation of the dispersion, and is not included in the dispersions 1 to 4.
Moreover, abbreviations and the like in Table 2 represent the following meanings.
PR122: C.I. I. Pigment Red 122, Cinquasia Magenta D4550J manufactured by BASF.
PV19: C.I. I. Pigment Violet 19, Cinquasia Magenta E05B manufactured by BASF.
PR122 + PR19: C.I. I. Pigment Red 122 and C.I. I. Pigment Red 19 solid solution, Inkjet Magenta E-02 manufactured by Clariant.
PR150: C.I. I. Pigment Red 150, FUJI FAST CARMINE 522-1D manufactured by Fuji Dye Co., Ltd.
SK-14: Olfine SK-14.

[Preparation Example 3] Preparation of polymer 1.
By pursuing “[Preparation Example 4] Preparation of polymer emulsion 3” in Patent Document 6, a polymer emulsion having an acid value of 6 mgKOH / g, Tg of 0 ° C., and a solid content of 24.9% was white suspension. Got as. This is designated as “Polymer 1”.

[Examples 1-3] and [Comparative Examples 1-4]: Preparation of ink for evaluation test.
After mixing each component of following Table 3, the ink of Examples 1-3 for evaluation tests and the comparative examples 1-4 was obtained by filtering with a 3 micrometer membrane filter, respectively.
In Table 1 below, solid content conversion values for polymer 1 and wax are described below. That is, each of the inks of Examples 1 to 3 contains 1 part of each of the polymer 1 and the wax as solid content converted values. The inks of Comparative Examples 1 and 3 contain 2 parts of polymer 1 as a solid content conversion value and do not contain wax. The inks of Comparative Examples 2 and 4 contain 2 parts of wax as a solid content converted value and do not contain polymer 1.
Abbreviations and the like in the following Table 3 represent the following meanings.
GLY: Glycerin.
DEG: Diethylene glycol.
2-PY: 2-pyrrolidone.
SF465: Surfynol 465, an acetylene-based surfactant manufactured by Nissin Chemical Industry Co., Ltd.
GXL (s): Proxel GXL (s).
Wax: AQUACER 515, wax produced by BYK (solid content 35.0%).

[Inkjet recording]
The ink obtained in each Example and Comparative Example was filled in an ink jet printer manufactured by Seiko Epson Corporation, PX204 cartridge, and ink jet recording was performed on a coated paper manufactured by Oji Paper Co., Ltd. and an OK top coat.
Inkjet recording was performed so as to obtain a 100% duty solid image, and a recorded image recorded with the ink of each example or comparative example was obtained. Using this as a test piece, the following evaluation test was conducted.
In addition, the color measurement of each test piece obtained as described above was performed using a colorimeter manufactured by X-rite, SpectroEye. The color measurement conditions are ANSI for the density standard, a viewing angle of 2 °, and a light source D50.

[Dry abrasion test]
The rubbing property of each test piece was measured by No. Evaluation was made using a 428 Gakushoku Dyeing Friction Fastness Tester. That is, with a 500 g load applied to the test piece, the ink jet recorded portion was rubbed 20 times, and the degree of image degradation was evaluated according to the following four evaluation criteria. The results are shown in Table 4 below.
Evaluation criteria for dry abrasion:
A: Color transfer to a blank paper surface and / or scratches on the image on the recording surface are hardly observed.
B: Color transfer to the white paper surface and / or image scratches on the recording surface are slightly observed.
C: Color transfer to the white paper surface and / or scratches on the image on the recording surface are clearly observed.
D: Color transfer to the white paper surface and scratches on the image on the recording surface are very large.

[Wet scratch test]
The wet fretting property of each test piece was measured by No. Evaluation was made using a 428 Gakushoku Dyeing Friction Fastness Tester. As the evaluation criteria, with the load of 500 g applied, the ink jet recorded portion was rubbed twice with a cloth moistened with water, and the degree of image degradation was evaluated according to the following evaluation criteria. The results are shown in Table 4 below.
Wet rub evaluation criteria:
A: Color transfer to the cloth and / or image scratches on the recording surface are slightly observed.
C: Color transfer to the cloth and / or image scratches on the recording surface are clearly observed.

[Color development test 1]
The reflection density Dm value (OD value) of each test piece obtained as described above was measured. The results are shown in Table 4 below.
[Color development test 2]
The reflection density Dm value (OD value) of each test piece after the wet scratch test obtained as described above was measured and evaluated according to the following four evaluation criteria. The results are shown in Table 4 below.
Evaluation criteria for color development:
A: The OD value is 1.4 or more.
B: The OD value is 1.2 or more and less than 1.4.
C: The OD value is 1.0 or more and less than 1.2.
D: OD value is less than 1.0.

  From the results of Table 4, the inks of Examples 1 to 3 containing both the polymer and the wax were compared to Comparative Examples 1 to 4 containing only one of the two in an amount of dry scratch, wet scratch, In addition, it was confirmed to have an excellent effect in color development.

  The method for improving scratchability of the present invention is very excellent in various scratch properties, particularly scratch properties in a wet state as well as in a dry state, and good color developability. For this reason, it is extremely useful as a method for improving the scratching properties of various recorded images.

Claims (6)

A method for improving the scratching property using an ink containing a quinacridone pigment and an azo pigment as a colorant and further containing a polymer, a wax, and water.
However, the monomer constituting the polymer contains a monomer selected from at least one of a methacrylic acid derivative and an acrylic acid derivative.   The method for improving scratch resistance according to claim 1, wherein the wax contains at least one selected from polyethylene wax, polypropylene wax, oxidized polyethylene wax, oxidized polypropylene wax and paraffin wax.   The quinacridone pigment is C.I. I. Pigment red 122, 202, and C.I. I. The method for improving scratch resistance according to claim 1, wherein the pigment is selected from CI Pigment Violet 19.   The method for improving scratch resistance according to claim 1, wherein the monomers constituting the polymer are three kinds of monomers selected from methacrylic acid derivatives and one kind of monomer selected from acrylic acid derivatives.   The method for improving scratch resistance according to claim 1 or 4, wherein the monomers constituting the polymer are two kinds of alkyl methacrylate, methacrylic acid, and alkyl acrylate.   The azo pigment is C.I. I. The method for improving scratch resistance according to claim 1, which is CI Pigment Red 150.