JP2018039857A - Method for improving scratch resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for improving scratch resistance of an image recorded on non-absorbable/hardly absorbable recording media having a low ink absorption capacity, particularly a method for improving scratch resistance of the same in a wet state.SOLUTION: The method for improving scratch resistance by using an ink containing a quinacridone pigment, an azo pigment, wax, a surfactant and water and containing no fluorine-based surfactant can solve the above-mentioned problem. The ink uses an ink containing no fluorine-based surfactant as the surfactant nor paraffin wax as the wax and having a total content of the wax of more than 0.1 mass% to less than 6 mass% based on the total mass of the ink.SELECTED DRAWING: None

Description

  The present invention relates to a method for improving scratch resistance using ink, and more particularly, to a method for improving scratch resistance of an image recorded on a non-hardly absorbable recording medium having a low ink absorption capability.

  A recording method using an ink jet printer (ink jet recording method) is one of typical methods among various color recording methods. In this method, ink droplets are generated and recorded on various recording media (paper, film, fabric, etc.) for recording. Until now, silver salt photographs and offset printing have been used for recording high-definition images. However, with the advancement of ink jet technology, the ink jet recording method has come to be used for recording high-definition images. In recent years, inkjet recording is being used for industrial purposes. In this application, an increase in recording speed is strongly demanded for ink jet recording.

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 Document 1 discloses an ink composition containing a colorant, a polymer dispersant, a wax agent, and a liquid medium.
Patent Document 2 discloses an ink composition containing a pigment, a resin having an anionic group, a wetting agent, a basic compound, a water-dispersible urethane resin, and a polyolefin wax.
Patent Document 3 discloses a dark ink and a light ink containing a pigment, a water-soluble resin, a resin emulsion, a paraffin wax emulsion, a polyethylene wax emulsion, an acetylene glycol surfactant, and a silicon surfactant independently of each other. Has been.

International Publication No. 2015/152291 Gazette International Publication 2011/093486 Gazette JP 2013-129711 A

  The present invention relates to a method for improving the scratch resistance of an image recorded on a non-hardly absorbable recording medium having a low ink absorption capability, particularly a method for improving the scratch resistance in a wet state (ie, a method for improving wet scratch resistance). Offering is an issue.

As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by an ink containing an azo pigment and a quinacridone pigment as colorants and further containing a wax, The present invention has been completed.
That is, the present invention relates to the following 1) to 11).
1)
A method for improving scratch resistance using an ink containing a quinacridone pigment, an azo pigment, a wax, a surfactant, and water and not containing a fluorosurfactant,
A method for improving scratching, wherein the ink does not contain paraffin wax as a wax, and the total content of the wax with respect to the total mass of the ink is more than 0.1% by mass and less than 6% by mass.
2)
The method for improving abrasion as described in 1) above, wherein the wax is a polyalkylene wax.
3)
The method for improving scratching properties according to 1) or 2), wherein the content of the wax with respect to the total mass of the ink is 0.5% by mass to 5% by mass.
4)
The quinacridone pigment is C.I. I. Pigment red 122, 202, and C.I. I. The method for improving scratching properties according to 1) above, wherein the pigment is selected from pigment violet 19.
5)
The azo pigment is C.I. I. The method for improving scratch resistance according to 1) above, which is CI Pigment Red 150.
6)
The scratch resistance improving method according to any one of 1) to 5), wherein the total content of the quinacridone pigment and the azo pigment is 0.1% by mass to 10% by mass with respect to the total mass of the ink.
7)
The scratch resistance improving method according to any one of 1) to 5), wherein the total content of the quinacridone pigment and the azo pigment is 3% by mass to 7% by mass with respect to the total mass of the ink.
8)
An ink containing a quinacridone pigment, an azo pigment, a wax, a surfactant, and water, and not containing a fluorosurfactant,
The ink does not contain paraffin wax as a wax, and ink droplets having a total wax content of more than 0.1% by mass and less than 6% by mass with respect to the total mass of the ink are recorded on a recording medium using an inkjet printer. The method for improving scratching according to any one of 1) to 7) above, which is a method for improving scratching of a recorded image obtained by adhering.
9)
The method for improving scratching properties according to 8), wherein the recording medium is cast-coated paper.
10)
The method for improving scratching properties according to 8), wherein the recording medium is coated paper or art paper.
11)
The rubbing according to any one of 8) to 10), wherein the recording medium is a recording medium whose surface is modified by at least one method selected from corona discharge treatment, plasma treatment, and flame treatment. How to improve sex.

  According to the present invention, there is provided a method for improving the scratching property of an image recorded on a non-difficult-absorbing recording medium having a low ink absorption capability, particularly a method for improving the scratching property in a wet state (that is, a method for improving wet scratching property). did it.

The above-mentioned method for improving the scratching property can be obtained by recording images on various recording media such as plain paper (preferably a recording medium not having an ink receiving layer), in particular, a non-difficult-to-absorbent recording medium having a low ink absorption capability. This is a method for improving the scratch resistance. Preferably, it is a method for improving wet abrasion.
Hereinafter, the ink used for the method for improving scratching will be described.
In this specification, “CI” means a color index.
Further, in the present specification, “%” and “part” are described on a mass basis unless otherwise specified, including examples.
In the present specification, “CI pigment red” and “CI pigment violet” are hereinafter referred to as “PR” and “PV” unless otherwise specified.

The ink contains two colorants, a quinacridone pigment and an azo pigment.
As a quinacridone pigment from the viewpoint of hue, transparency, color developability, saturation, light resistance and the like, a di-substituted quinacridone pigment is preferable, and a red di-substituted quinacridone pigment is more preferable. The di-substituted quinacridone pigment means a quinacridone pigment having a chemical structure in which any two hydrogen atoms on the benzene ring of unsubstituted quinacridone are substituted with a substituent other than a hydrogen atom. Examples of the substituent other than a hydrogen atom include a methyl group, a methoxy group, and a chlorine atom. Among them, a pigment selected from PR122, PR202, and PV19 is preferable, and in consideration of color developability, one type selected from PV19 or PR122 or a combination thereof is more preferable.
Similarly, PR150 is preferred as the azo pigment.

The total content of the two colorants of quinacridone pigment and azo pigment with respect to the total mass of the ink is usually 0.1% to 10%, preferably 0.5% to 8%, more preferably 1% to It is 8%, more preferably 3% to 7%.
When the total content of the colorant is 0.1% or more, the color developability of the recorded image is good, and when it is 10% or less, the discharge property is good.

  The content ratio of the quinacridone pigment to the azo pigment in the total mass of the colorant 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 color development and saturation can be obtained.

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 microcrystalline waxes, which are petroleum waxes, montan waxes, which are brown coal waxes, carnauba waxes, canderia waxes, etc., such as plant waxes, beeswax, lanolin, etc., which are animal and plant waxes. An emulsion dispersed therein can be mentioned. However, paraffin wax is excluded.
These waxes can be used alone or in combination.

  As the wax, polyalkylene waxes such as polyethylene wax, polypropylene wax, and polybutylene wax are particularly preferable. When only the polyalkylene wax is used as the wax, the scratching property can be improved.

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

  Products commercially available as wax emulsions include, for example, CERAFLOUR 925, CERAFLOUR 929, CERAFLOUR 950, CERAFLOUR 991, AQUACER 498, AQUACER 515, AQUACER 531, AQUACER 537, AQUACER 539, AQUACER 539, AQUACER 539, AQUACER 539, AQUACER 539, AQUACER 539, AQUACER 539 Mitsui High Wax NL100, Mitsui High Wax NL200, Mitsui High Wax NL500, Mitsui High Wax 4202E, Mitsui High Wax 1105A, Mitsui High Wax 2203A, Mitsui High Wax NP550, Mitsui High Wax NP05 , It includes Mitsui Hi-wax NP505 and the like.

  Among these waxes, AQUACER515, AQUACER531, AQUACER537, AQUACER539, and AQUACER1547 are preferable, and AQUACER515, AQUACER531, AQUACER537, and AQUACER1547 are more preferable.

  The wax content in the total mass of the ink is usually more than 0.1% and less than 6%. Preferably, it is 0.5% to 5%. By setting the content of the wax within this range, the scratching property is improved.

  The ink can be used alone or in combination with other color inks. For the purpose of obtaining a full-color recorded image, usually three-color inks of cyan, yellow, and magenta, and four-color inks obtained by adding black ink to these inks are used. At this time, the ink is preferably used as a magenta ink. Further, the colorant contained in each ink of cyan, yellow and black is not particularly limited, and a known colorant 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

The following describes the colorants that each color ink can contain for the purpose of obtaining a full-color recorded image.
A pigment is preferable as the colorant, and examples thereof include inorganic pigments, organic pigments, and extender pigments. The colorants can be used alone or in combination.
The purpose of using the pigment in combination is to adjust the hue. The purpose of adjusting the hue includes, for example, adding a shade to the recorded image and widening the color gamut. In addition, when a plurality of colorants are used in combination, the storage stability in the ink may be improved as compared with the case where a single colorant is contained.

Specific examples of organic pigments contained in the cyan, yellow, black, violet, orange to brown, and green inks include C.I. I. Pigment Blue 1, 2, 3, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 25, 60, 66, 80, etc. cyan (blue) pigments C. I. Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 24, 55, 73, 74, 75, 83, 93, 94, 95, 97, 98, 108, 114, 120, 128, 129, 138, 139, 150, 151, 154, 155, 180, 185, 193, 199, 202, 213 and the like yellow pigments; I. Pigment Black 1 and other black pigments; C.I. I. Pigment Violet 19, 23, 29, 37, 38, 50 and the like violet pigments; C.I. I. Pigment Orange 13, 16, 68, 69, 71, 73 and the like orange-brown pigments; C.I. I. Pigment Green 7, 36, 54, etc. Green pigments;
Among these, C.I. I. Pigments selected from the group consisting of Pigment Yellow 74, 151, and 155 are preferred. Cyan (blue) pigments include C.I. I. Pigments selected from Pigment Blue 15: 3 and 15: 4 are preferred.

  Examples of the inorganic pigment include carbon black, metal oxide, hydroxide, sulfide, ferrocyanide, and metal chloride. In particular, carbon black is preferable as the pigment contained in the black ink. Examples of carbon black include thermal black, acetylene black, oil furnace black, gas furnace black, lamp black, gas black, and channel black. Of these, gas furnace black, lamp black, acetylene black, and channel black are preferable.

  The carbon black can be easily obtained as a commercial product. Specific examples thereof include, for example, the Raven series manufactured by Columbian Carbon; the Monarch series, Regal series, and Mogu series manufactured by Cabot; the Color Black series, the Printex series, the Special Black series, the Nerox series manufactured by Orion Engineered Carbons; Examples include MA series and MCF series manufactured by Kagaku Corporation.

  Examples of organic pigments include azo pigments, diazo pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, dioxazine pigments, perylene pigments, perinone pigments, thioindigo pigments, anthraquinone pigments, and quinophthalone pigments.

  Examples of extender pigments include silica, calcium carbonate, talc, clay, barium sulfate, and white carbon. These extender pigments can be used alone. However, it is usually used in combination with an inorganic pigment or an organic pigment.

  The total pigment content in the total mass of each ink such as cyan, yellow, and black is usually 0.5% to 10%, preferably 0.5% to 8%, more preferably 1% to 8%. More preferably, it is 2% to 7%.

  As the colorant, from the viewpoint of safety and dischargeability, for example, synthetic materials having mutagenicity, various metal salts such as calcium, other organic impurities, by-products generated during synthesis, etc. are not included as much as possible. Is preferred.

  Examples of the surfactant include known surfactants such as anion, cation, nonion, amphoteric, and silicone. The surfactant content in the total mass of the ink composition is generally 0.01 to 3%, preferably 0.01 to 2.5%, more preferably 0.02 to 2.0%. However, the ink does not contain a fluorinated surfactant.

  Examples of anionic surfactants include alkyl sulfocarboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, polyoxyethylene alkyl ether sulfates, N-acyl amino acids or salts thereof, N-acyl methyl taurate, Alkyl sulfate polyoxyalkyl ether sulfate, alkyl sulfate polyoxyethylene alkyl ether phosphate, rosin acid soap, castor oil sulfate ester, lauryl alcohol sulfate ester, alkylphenol type phosphate ester, alkyl type phosphate ester, alkylaryl sulfone Acid salts, diethylsulfosuccinate, diethylhexylsulfosuccinate, dioctylsulfosuccinate and the like. Specific examples of commercially available products include, for example, Hightenol LA-10 manufactured by Daiichi Kogyo Seiyaku Co., Ltd. LA 12, LA-16, neo-Hitenol ECL-30S, ECL-45 and the like.

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

  Nonionic surfactants include ethers such as polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether; Ester systems such as polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate, polyoxyethylene stearate; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl Acetylene glycol (alcohol) type such as lu-1-hexyn-3-ol; trade name Surfinol 104, 105PG50, 82, 420, 440, 465, 485, Olphine STG manufactured by Nissin Chemical Co., Ltd .; Polyglycol ether type (For example, TergItol15-S-7 manufactured by SIGMA-ALDRICH);

  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.

Examples of the silicon surfactant include polyether-modified siloxane and polyether-modified polydimethylsiloxane. Among them, polyether-modified polydimethylsiloxane represented by the following formula (2) is preferable.
Examples of commercially available silicon surfactants include, for example, DYNOL 960 and DYNOL 980 manufactured by Air Products; Sylface SAG001, Sylface SAG002, Sylface SAG003, Sylface SAG005, Sylface SAG503A, manufactured by Nissin Chemical Co., Ltd. Sylface SAG008, Sylface SAG009, Sylface SAG010; BYK-345, BYK-347, BYK-348, BYK-349, BYK-3455 and the like manufactured by Big Chemie.

The ink preferably contains 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, 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%, based on the total mass of the pigment, in terms of solid content when preparing the dispersion. is there. By setting the amount of the dispersant to be used in this range, it is possible to make the pigment finer and to improve the bleeding, water resistance, scratch resistance, and the like of the recorded image.

  Nonionic dispersants include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene polyoxypropylene glycol, glycerin ester, sorbitan ester, sucrose ester, glycerin ester polyoxyethylene ether, sorbitan ester polyoxy Ethylene ether, polyoxyethylene ether of sorbitol ester, fatty acid alkanolamide, polyoxyethylene fatty acid amide, amine oxide, polyoxyethylene alkylamine, polyoxyethylene-β-naphthyl ether, polyoxyethylene styrylphenyl ether, polyoxyethylene dis And tillphenyl ether.

  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, polyphosphates Examples thereof include oxyethylene alkyl ether phosphate esters, alkyl allyl ether phosphates, polyoxyethylene alkyl ether sulfates, polyoxyethylene styryl phenyl ether sulfates, and polyoxyethylene distyryl phenyl ether sulfates.

Examples of the polymer dispersant include styrene and derivatives thereof; vinyl naphthalene and derivatives thereof; α, β-ethylenically unsaturated carboxylic acid and / or aliphatic alcohol esters thereof; acrylic acid and derivatives thereof; methacrylic acid and derivatives thereof Maleic acid and derivatives thereof; itaconic acid and derivatives thereof; fumaric acid and derivatives thereof; vinyl acetate, vinyl alcohol, vinyl pyrrolidone, acrylamide, and derivatives thereof; at least two selected from the group consisting of monomers Copolymers comprising monomers (preferably at least one each of a hydrophobic monomer and a hydrophilic monomer), such as block copolymers, random copolymers and graft copolymers Is mentioned. Moreover, when these copolymers have an acidic group and / or a basic group, these groups can be used by appropriately neutralizing them.
As a weight average molecular weight of a dispersing agent, it is about 1000-30000, Preferably it is 1250-25000, More preferably, it is about 1500-20000. Moreover, as an acid value, it is about 80-300, Preferably it is 90-275, More preferably, it is about 100-250.
Specific examples of the commercially available dispersant include, for example, Joncrill 61J, 67, 68, 450, 55, 555, 586, 678, 680, 682, 683, 690, all manufactured by BASF Corporation; and B-36 etc. are mentioned.

  The method for preparing the ink is not particularly limited, and a known method can be used. As an example, for example, a colorant and a dispersant are mixed by stirring using a sand mill (also called a bead mill), a roll mill, a ball mill, a paint shaker, an ultrasonic disperser, a microfluidizer, and the like. An aqueous dispersion is prepared. An ink can be prepared by adding and mixing a water-soluble organic solvent, water and, if necessary, an additive such as an ink preparation agent to the obtained aqueous dispersion. The order of adding the additives and the like is not particularly limited, and the aqueous dispersion can be added after adding the water-soluble organic solvent and the ink preparation agent to water.

  The ink and the dispersion liquid can remove impurities and the like by performing microfiltration using a membrane filter, glass filter paper, or the like as necessary. When microfiltration is performed, the pore size of the filter or the like is usually about 0.5 μm to 20 μm, preferably about 0.5 μm to 10 μm.

  As the pigment, a so-called surface-treated pigment (self-dispersed pigment) in which a dispersibility-imparting group is chemically introduced on the surface of the pigment can be used. In this case, the pigment can be dispersed in the aqueous medium without using a dispersant.

The average particle diameter of the colorant in the aqueous dispersion of the colorant is usually 200 nm or less, preferably 50 nm to 200 nm, more preferably 70 nm to 170 nm, and still more preferably 80 nm to 130 nm.
Moreover, D90 of a coloring agent is 300 nm or less normally, Preferably it is 250 nm or less, More preferably, it is 200 nm or less. The lower limit is preferably 100 nm or more.
D10 of the colorant is usually 10 nm or more, preferably 20 nm or more, more preferably 30 nm or more and 50 nm or less.
When the average particle diameter, D90 and D10 are in such a range, the storage stability, the discharge property, and the print density of the aqueous dispersion of the colorant and / or the ink containing the same are improved. In addition, the aqueous dispersion and / or ink can be easily produced.

  Examples of the water used for preparing the aqueous dispersion of the colorant and the ink include distilled water, ion-exchanged water, pure water, and ultrapure water having a pH of 6.5 to 7.5, and Water with a low content of various impurities is preferred.

  The ink is, for example, a water-soluble organic solvent, an antifungal agent, an antiseptic, a pH adjuster, a chelating reagent, a rust inhibitor, a water-soluble ultraviolet absorber, a water-soluble polymer compound, an antioxidant, a surfactant, etc. An ink preparation agent can be contained as required.

Examples of the water-soluble organic solvent include C1- such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol or tert-butanol, 1,2-hexanediol, 1,6-hexanediol, trimethylolpropane, and the like. C6 alkanol; carboxylic acid amides such as N, N-dimethylformamide or N, N-dimethylacetamide; lactams such as 2-pyrrolidone, N-methyl-2-pyrrolidone or N-methylpyrrolidin-2-one; Cyclic ureas such as dimethylimidazolidin-2-one or 1,3-dimethylhexahydropyrimido-2-one; ketones such as acetone, 2-methyl-2-hydroxypentan-4-one, ethylene carbonate; Ketoalcohol; tetrahydrofuran, dioxane Cyclic ethers of ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,4-butylene glycol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol , Tetraethylene glycol, dipropylene glycol, mono-, oligo- or polyalkylene glycol or thio having C2-C6 alkylene units such as polyethylene glycol having a molecular weight of 400, 800, 1540 or higher, polypropylene glycol, thiodiglycol or dithiodiglycol Glycol; polyol (triol) such as glycerin, diglycerin, hexane-1,2,6-triol; ethylene glycol monomethyl ether, ethylene glycol Cole monoethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol), triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol monoallyl ether, ethylene glycol monoisopropyl ether, diethylene glycol monomethyl ether, propylene glycol Examples thereof include C1-C4 alkyl ethers of polyhydric alcohols such as monopropyl ether and triethylene glycol monobutyl ether; γ-butyrolactone and dimethyl sulfoxide.
The content of the water-soluble organic solvent in the total mass of the ink is usually 5% to 60%, preferably 5% to 50%, more preferably 10% to 40%.

  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. .

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 or sodium benzoate, manufactured by Arch Chemical Co., Ltd., trade names Proxel GXL (S), Proxel LV, Proxel XL-2 (S) and the like. .

  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); or alkali metal carbonates such as lithium carbonate, sodium carbonate, sodium hydrogen carbonate and potassium carbonate; alkali metal salts of organic acids such as sodium silicate and potassium acetate; inorganic bases such as disodium phosphate It is done.

  Specific examples of the chelating reagent include, for example, disodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate or sodium uracil diacetate.

  Specific examples of the rust inhibitor include acidic sulfite, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate or dicyclohexylammonium nitrite.

  Examples of water-soluble UV absorbers include sulfonated benzophenone compounds, benzotriazole compounds, salicylic acid compounds, cinnamic acid compounds, and triazine compounds.

  The water-soluble polymer compound is not particularly limited as long as it is a polymer that dissolves in water, but anionic polymers and nonionic polymers are preferred from the viewpoint of dispersion stability. Specific examples of the anionic polymer include cellulose derivatives such as carboxymethyl cellulose, acrylic acid derivatives such as polyacrylic acid, and polystyrene derivatives such as polystyrene sulfonate. Specific examples of the nonionic polymer include polyethylene glycol, polyvinyl alcohol, polyvinyl pyrrolidone, gelatin and the like.

  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 or heterocyclic rings. .

Examples of the surfactant include known surfactants such as an anionic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, a fluorosurfactant, and a silicone surfactant. It is done. Among these, at least one surfactant selected from the group consisting of an anionic surfactant, a nonionic surfactant, and a silicone-based surfactant is preferable.
The total content of surfactants contained in the ink is usually 0.1% to 3%, preferably 0.3% to 1.5%, based on the total mass of the ink.
If it is 0.1% or less, the effect as a surfactant cannot be obtained, and if it is 3% or more, there is a problem in the dispersion stability of the pigment.

  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 sulfate ester salt, alkylphenol type phosphate ester, alkyl type phosphate ester, alkylaryl sulfonate, diethylsulfate, diethylhexylsulfate, dioctylsulfate, etc. It is below. Moreover, as a specific example of what can be obtained as a commercial item, for example, Haitenol LA-10, LA-12, LA-16, NE-05, NE-15, NF-13, NF-17, Neohaitenol ECL- 30S, ECL-45 (Daiichi Kogyo Seiyaku Co., Ltd.), Adeka Coal EC-8600 (Adeka), Perex OT-P (Kao), etc. Among these, at least one selected from the group consisting of polyoxyethylene dinonyl phenyl ether sulfate, polyoxyethylene lauryl ether sulfate, and dioctyl sulfosuccinate is preferable.

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

  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, Sobutanol TMEP-5035, 7085, 9050 manufactured by Nippon Shokubai, Pluronic TML-31, L-34, L-44 manufactured by Adeka, etc.); polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate , Sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene monooleate, polyoxyethylene stearate, etc. 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1-hexyne- Acetylene glycol (alcohol) system such as 3-ol; polyoxyethylene acetylene glycol ether; polyoxyethylene distyrenated phenyl ether; polyoxyethylene tribenzylated phenyl ether; both Surfinol 104, 104PG50 manufactured by Nissin Chemical Co., Ltd. , 105PG50, 82, 420, 440, 465, 485; Olphine STG; Polyglycol ether type (for example, TegItol15-S-7 manufactured by SIGMA-ALDRICH); and the like. Among these, at least one selected from the group consisting of polyoxyethylene acetylene glycol ether, polyoxyethylene distyrenated phenyl ether, and polyoxyethylene tribenzylated phenyl ether is preferable.

  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.

  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. These antifoaming agents can be used alone or in combination of two or more.

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 approximately 1% or less with respect to the total mass of the dye, and the lower limit may be less than the detection limit of the analytical instrument, that is, 0%.
Inorganic impurities are often mixed in the colorant. For this reason, if necessary, for example, a method of suspending and purifying a dried product of a colorant or a wet cake in a mixed solvent of (C1-C4) alcohol such as methanol and water; The inorganic impurities can be removed by a method of exchanging and adsorbing inorganic impurities with an ion exchange resin;

The pH of the ink is usually pH 7 to 11, preferably pH 8 to 10.
The surface tension of the ink is usually 10 to 50 mN / m, preferably 20 to 40 mN / m.
The viscosity of the ink is usually 2 mPa · s to 30 mPa · s, preferably 3 mPa · s to 20 mPa · s or less.

  The method for improving scratching can be used for various recorded images. The recorded image can be obtained by attaching the ink to a recording medium by various methods such as writing, printing, and textile printing. Among these, a recorded image obtained by attaching the ink to a recording medium using an ink jet printer is particularly preferable.

  Any known method can be used as the ink jet method. For example, charge control method; pressure pulse method; acoustic ink jet method; thermal ink jet method;

  The recording medium is not particularly limited as long as it is a substance colored by the ink, and examples thereof include paper, film, fiber and cloth (cellulose, nylon, wool, etc.), leather, and a color filter base material. Among these, a recording medium having no ink receiving layer is preferable.

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.

  The recording medium is preferably a recording medium whose surface is modified by at least one method selected from corona discharge treatment, plasma treatment, and flame treatment. For these processes, any known method may be used. In addition, it is generally known that the effects of these treatments decrease with time. For this reason, when the surface of the recording medium is modified, it is preferable to form a recorded image without taking time.

  Examples of the corona discharge treatment include a method in which a corona discharge is generated by applying a high voltage of several thousand volts between a grounded metal roll and a wire-like electrode placed at intervals of several mm. By disposing and treating the recording medium between the electrode and the roll during the corona discharge, the surface of the sheet is hydrophilized.

  As the plasma treatment, the recording medium is placed in a container containing argon, neon, helium, nitrogen, nitrogen dioxide, oxygen, air, or the like, and exposed to plasma generated by glow discharge, so that oxygen, nitrogen, etc. are applied to the surface of the sheet. The method of introduce | transducing the functional group to contain is mentioned.

  The flame treatment is also referred to as flame treatment. For example, there is a method of improving the hydrophilicity by spraying a gas oxidation flame or the like sprayed from a burner or the like on the surface of the recording medium to oxidize the surface of the sheet.

  Each of the above processes can be performed by appropriately adjusting the number of times, time, applied voltage, and the like so that a desired effect can be obtained.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by a following example.
In addition, content of the solid content in a dispersion solution was calculated | required by the dry weight method using A & D Co., Ltd. make and MS-70. 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 dispersant.
Joncrill 678 (20 parts), triethanolamine (11.4 parts), and ion-exchanged water (68.6 parts) were added to a three-necked flask equipped with a condenser, and the temperature was raised to 90 ° C. while stirring at 150 rpm. A solution was obtained by warming to obtain an aqueous solution containing 20% of Joncryl 678.
“JC678” in the following Table 1 means an aqueous solution containing 20% of this Jonkrill 678.

[Preparation Example 2]: Preparation of dispersion 1.
Using PR122 as the quinacridone red pigment, the components described in Table 1 below were mixed, and dispersion treatment was performed for 15 hours using a sand grinder at 1500 rpm. The obtained liquid was diluted with ion-exchanged water, and the dispersion beads were separated by filtration to obtain a dispersion 1 having a pigment solid content of 14.9% and an average particle diameter of 87 nm.
In Tables 1 to 3 below, the numerical values indicating the amounts of components are all “parts”, and “−” indicates that the component is not included. In addition, “water” used ion-exchanged water. Further, “Olfin SK-14” is an antifoaming agent and is not contained in the inks of Examples and Comparative Examples because it is removed by filtration.

[Preparation Examples 3 to 5]: Preparation of dispersions 2 to 4.
Dispersions 2 to 4 were obtained in the same manner as in Preparation Example 2, except that the red pigment described in Table 1 below was used instead of the red pigment used in Preparation Example 2.
In addition, as the red pigment in Table 1, the following pigments were used.
PR122: Cinquasia Magenta D4550J manufactured by BASF.
PR150: FUJI FAST CARMINE 522-1D manufactured by Fuji Color Co., Ltd.
PV19: Cinquasia Magenta E05B manufactured by BASF.
PR122 / PV19: Inkjet Magenta E-02 manufactured by Clariant (solid solution of PR122 and PV19).
“SK-14” is “Orphine SK-14”.

[Preparation Examples 6 to 20]: Preparation of ink for evaluation test.
The components described in Table 2 below were mixed and sufficiently stirred to obtain a liquid. By filtering the obtained liquid with a 3 μm membrane filter, Examples 1 to 7 for evaluation tests and Comparative inks 1 to 8 were obtained.
Moreover, abbreviations and the like in Table 2 represent the following meanings.
GLY: Glycerin.
DEG: Diethylene glycol.
2-PY: 2-pyrrolidone.
SF-465: Surfynol 465.
GXL (s): Proxel GXL (s).
AQ515: AQUACER515.
Friction property 1: Results of the following dry fretting test.
Scratch 2: Results of the following wet scratch test.

[Evaluation test]
The following evaluation tests were performed on the inks of the examples and comparative examples obtained as described above. The evaluation results are shown in Table 2.

[Preparation of recorded image using inkjet printer]
Using a Seiko Epson ink jet printer (trade name PX205), each test ink obtained as described above was adhered to a coated paper to obtain a recorded image. As the coated paper, an OK top coat manufactured by Oji Paper Co., Ltd. was used.
As a recorded image, a solid image of 100% Duty was obtained. Using this as a test piece, the following two evaluation tests were performed.
When color measurement is necessary, a colorimeter manufactured by X-rite, trade name SpectroEye was used. The color measurement conditions are ANSI for the density standard, a viewing angle of 2 °, and a light source D50.
Further, the cloth used in (C) and (D) is Alpha Wipe TX1009 manufactured by Texwipe.

[Dry Friction (Abrasion 1) Test]
The recorded image of each test piece and the blank surface of the OK topcoat before printing were superimposed. No. made by Yasuda Seiki Seisakusho Co., Ltd. Using a 428 Gakushoku Dyeing Friction Fastness Tester, rubbing 20 times under a load of 500 g, measuring the reflection density Dm value of the recorded image of each test piece before and after the test, and measuring the difference in image density Evaluation was made in the following three stages A to C.
A: The density difference before and after the test is less than 4%.
B: The density difference before and after the test is 4% or more and less than 7%.
C: The concentration difference before and after the test is 7% or more.

[Wet scuffing (scratching 2) test]
For the recorded image portion of each test piece, No. Using a 428 Gakushoku Dyeing Friction Fastness Tester, a recorded image of each test piece was rubbed twice with a cloth moistened with water under a load of 500 g. The reflection density Dm value of the image portion was measured, and the density difference of the image was evaluated in the following three grades AC.
A: The density difference before and after the test is less than 38%.
B: The concentration difference before and after the test is 38% or more and less than 40%.
C: Concentration difference before and after the test is 40% or more.

As is clear from Table 2, each test result of dry scratch property and wet scratch property of each example was good with good balance. On the other hand, in each comparative example, at least one of those test results showed "C", and it was confirmed that it was extremely inferior to each example.
Further, as apparent from the test results of the comparative examples, it was found that there was no correlation between the dry and wet scratch test results.

  The method for improving scratch resistance of the present invention is extremely useful as a method for improving the scratch resistance of images recorded on various recording media such as plain paper, in particular, non-absorptive recording media with low ink absorption capability. .

Claims (11)

A method for improving scratch resistance using an ink containing a quinacridone pigment, an azo pigment, a wax, a surfactant, and water and not containing a fluorosurfactant,
A method for improving scratching, wherein the ink does not contain paraffin wax as a wax, and the total content of the wax with respect to the total mass of the ink is more than 0.1% by mass and less than 6% by mass.   2. The method for improving scratch resistance according to claim 1, wherein the wax is a polyalkylene wax.   The method for improving scratch resistance according to claim 1 or 2, wherein the content of the wax with respect to the total mass of the ink is 0.5 mass% to 5 mass%.   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 pigment violet 19.   The azo pigment is C.I. I. The method for improving scratch resistance according to claim 1, which is CI Pigment Red 150.   The scratch content improving method according to any one of claims 1 to 5, wherein the total content of the quinacridone pigment and the azo pigment is 0.1% by mass to 10% by mass with respect to the total mass of the ink.   The method for improving scratch resistance according to any one of claims 1 to 5, wherein the total content of the quinacridone pigment and the azo pigment is 3% by mass to 7% by mass with respect to the total mass of the ink. An ink containing a quinacridone pigment, an azo pigment, a wax, a surfactant, and water, and not containing a fluorosurfactant,
The ink does not contain paraffin wax as a wax, and ink droplets having a total wax content of more than 0.1% by mass and less than 6% by mass with respect to the total mass of the ink are recorded on a recording medium using an inkjet printer. The method for improving scratch resistance according to any one of claims 1 to 7, which is a method for improving scratch resistance of a recorded image obtained by adhesion.   The method according to claim 8, wherein the recording medium is cast coated paper.   The method according to claim 8, wherein the recording medium is coated paper or art paper.   The scratch property according to any one of claims 8 to 10, wherein the recording medium is a recording medium whose surface is modified by at least one method selected from corona discharge treatment, plasma treatment, and flame treatment. How to improve.