JP2003147252A - Water-based printing ink composition and printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water-based printing ink composition suitably used for printing of paper, plastic film, or the like, particularly photogravure printing and flexographic printing and excellent in wearabilities to cylinders, doctor blades and anilox rolls and to provide a printing method using the ink composition. SOLUTION: The water-based printing ink composition comprises a carboxyl group-containing ethylene-α-olefin copolymer (a), a water-based resin (b) and a neutralizing agent. The component (a) is preferably composed of one or more kinds of compounds selected from an unsaturated carboxylic acid and its anhydride, ethylene and an α-olefin. The printing method comprises using this ink composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aqueous printing ink composition suitable for printing on paper, plastic film and the like. More specifically, it relates to a water-based printing ink composition which is suitably used for gravure printing and flexographic printing and is excellent in cylinder wearability, doctor blade wearability, and anilox roll wearability.

[0002]

2. Description of the Related Art Gravure printing and flexographic printing are widely used for the purpose of imparting beauty and functionality to a material to be printed. In recent years, there has been an increasing demand in the printing ink industry for water-based printing inks from the standpoint of the risk of fire due to organic solvents.

In gravure printing, printing ink is supplied to a gravure cylinder having cells formed on the surface, excess printing ink on the cylinder surface is scraped off by a doctor blade, and then printing is performed on a printing medium such as paper or plastic. It is a thing. However, in the conventional printing using the water-based printing ink composition, there is a drawback that the life of the doctor blade and the cylinder is shorter than that of the solvent-based printing ink, so that it has to be replaced frequently. Furthermore,
As the doctor blade wears, the excess printing ink on the cylinder surface is not scraped off sufficiently, and printing is performed on the margins (non-image areas) where the printing ink on the paper or film, which is the original material to be printed, should not be transferred. There is a problem that printing defects such as plate fogging that ink adheres occur. Also,
There is also a problem that when the wear of the cylinder progresses, the transfer amount of the printing ink decreases and the original printing density cannot be obtained, resulting in printing failure.

As a printing method for flexographic printing, there are a two-roll method, a doctor method, and a doctor chamber method. Both the doctor method and the doctor chamber method have a step of supplying printing ink to an anilox roll having cells formed on the surface and scraping off excess printing ink on the anilox roll surface by a doctor blade. When a conventional water-based printing ink composition is used, there is a drawback that the life of the doctor blade and the anilox roll is short. Further, as the abrasion of the anilox roll progresses, there is a problem in that the transfer amount of the printing ink is reduced and the original printing density cannot be obtained, resulting in printing failure.

[0005]

The object of the present invention is to overcome the above-mentioned drawbacks which cannot be solved by the existing aqueous printing ink compositions based on the prior art. That is, it is to provide a water-based printing ink composition having excellent cylinder wearability, doctor blade wearability, and anilox roll wearability.

[0006]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to solve the above-mentioned conventional problems, the carboxyl group-containing ethylene / α-olefin copolymer (a) was treated with an aqueous resin ( The present invention has been found out that when a water-based printing ink composition containing b) as a binder is contained, it has excellent lubricity and can significantly reduce cylinder wear, doctor blade wear, and anilox roll wear.

That is, the first invention of the present invention is an aqueous printing ink composition comprising a carboxyl group-containing ethylene / α-olefin copolymer (a), an aqueous resin (b) and a neutralizing agent. It is a thing.

A second invention is that the carboxyl group-containing ethylene / α-olefin copolymer (a) is composed of one or more kinds selected from unsaturated carboxylic acids or their anhydrides, ethylene, and an α-olefin. The water-based printing ink composition according to the first invention is characterized.

The third invention is that the content of the carboxyl group-containing ethylene / α-olefin copolymer (a) is 0.1-2.
The water-based printing ink composition according to the first or second invention is in the range of 0% by weight.

A fourth invention is the aqueous printing ink composition according to any one of the first to third inventions, wherein the neutralizing agent is a volatile organic basic compound.

A fifth invention is a printing method characterized by using the aqueous printing ink composition according to any one of the first to fourth inventions.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the water-based printing ink composition of the present invention will be described in detail. The carboxyl group-containing ethylene / α-olefin copolymer (a) used in the aqueous printing ink composition of the present invention comprises ethylene and an α-olefin, and at least one selected from unsaturated carboxylic acids or their anhydrides. Become.

The ethylene / α-olefin copolymer which is a constituent of the carboxyl group-containing ethylene / α-olefin copolymer (a) is a compound having a structure represented by the following chemical formula (1). For example, in the presence of hydrogen, It can be produced by continuously copolymerizing ethylene and an α-olefin in a liquid phase using a catalyst formed of a soluble vanadium compound and an organoaluminum compound.

[0014]

[Chemical 1]

The ethylene content in the ethylene / α-olefin copolymer is preferably 30 to 70 mol%, particularly 40 to 60 mol%.
Mol% is preferred.

As the α-olefin as a copolymerization component,
For example, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1
-Tetradecene, 1-hexadecene, 1-octadecene, 4-methyl-1-pentene and the like having 3 to 20 carbon atoms can be mentioned. Of these, those having 3 to 14 carbon atoms are more preferable, and those having 8 to 14 carbon atoms are particularly preferable. These can be used alone or in combination of two or more.
The number average molecular weight of ethylene / α-olefin copolymer is 500
It is preferably ˜10,000. Also, a liquid at room temperature is preferable, and Q value (weight average molecular weight / number average molecular weight)
Is 3 or less, particularly preferably 2.8 or less. The molecular weight in the present invention is a value obtained in terms of polystyrene in gel permeation chromatography (GPC) measurement.

Examples of unsaturated carboxylic acids and their anhydrides include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid and bicyclo [2,1,1].
Pept-2-ene-5,6-dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, bicyclo [2,
Examples include unsaturated carboxylic acids such as 1,1] pept-2-ene-5,6-dicarboxylic acid anhydride and anhydrides thereof. These can be used alone or in combination of two or more. The method for producing the carboxyl group-containing ethylene / α-olefin copolymer (a) is not particularly limited.
It can be produced by graft-modifying an α-olefin copolymer with an unsaturated carboxylic acid or its anhydride. Graft modification can be carried out, for example, by reacting an ethylene / α-olefin copolymer with a graft component in the presence of a radical generator peroxide such as ditertiary butyl peroxide.

The carboxyl group-containing ethylene / α-olefin copolymer (a) is 1 to 20% by weight, particularly 3 to 15% by weight.
It is preferable to have the graft-modifying component because it has good mixability with ink, stability when added to ink, and stability when emulsified.

The carboxyl group-containing ethylene as described above
The α-olefin copolymer (a) has a number average molecular weight of 500 to 10,
000, especially 600 to 5,000 is preferred. Further, the Q value (weight average molecular weight / number average molecular weight) is preferably 3 or less, particularly preferably 2.8 or less, and the property thereof is a liquid or semi-solid copolymer at room temperature, but more preferably a liquid at room temperature. The method for producing the carboxyl group-containing ethylene / α-olefin copolymer (a) is reported in, for example, Japanese Patent Publication No. 7-88493.

The content of the carboxyl group-containing ethylene / α-olefin copolymer (a) in the water-based printing ink composition of the present invention is such that sufficient lubricity, cylinder wearability, and
From the viewpoint of obtaining the doctor blade wearability and the anilox roll wearability, the range is preferably 0.1% by weight or more, and from the viewpoint of sufficient blocking resistance, the range is preferably 20% by weight or less, more preferably 0.5 to 10% by weight. preferable.

The carboxyl group-containing ethylene / α-olefin copolymer (a) is incorporated into the aqueous printing ink composition by a conventionally known method. The composition may be, for example, at the time of producing an aqueous printing ink composition, or an ink composition not containing (a) may be produced in advance, and (a) may be incorporated immediately before printing to obtain a printing ink composition. Alternatively, (a) may be further added to the printing ink composition just before the printing operation. The addition may be either (a) or an aqueous emulsion (a). When (a) is added immediately before the printing operation to obtain an aqueous printing ink composition, it is preferable to use an aqueous emulsion from the viewpoint of workability and mixability with the ink composition.

Since the carboxyl group-containing ethylene / α-olefin copolymer (a) itself has a surface-active property, an aqueous emulsion can be prepared without using a surfactant. For example, it can be produced by stirring in the presence of water using a device such as a stirrer type emulsifier, a colloid mill or an ultrasonic emulsifier under temperature conditions in the range of room temperature to 100 ° C. However, when the graft-modifying component is 3% by weight or less, or when the non-graft-modified ethylene / α-olefin copolymer is used in combination with the carboxyl group-containing ethylene / α-olefin copolymer (a), a surfactant is used. It is easier to emulsify and the produced emulsion is more stable. The surfactant used may be any of nonionic surfactants, anionic surfactants and cationic surfactants. As the nonionic surfactant, for example, polyoxyethylene alkyl ether, polyoxyethylene alkylamine, etc., as the anionic surfactant, for example, fatty acid salt, alkylbenzene sulfonate, etc., as the cationic surfactant, Examples include quaternary ammonium salts.

The aqueous emulsion may contain the carboxyl group-containing ethylene / α-olefin copolymer (a) in an amount of 10 to 90% by weight, more preferably 20 to 50% by weight. Water can be contained in a proportion of 90 to 10% by weight, more preferably 80 to 50% by weight. When a surfactant is used, it can be contained in a proportion of 0.5 to 30% by weight, more preferably 3 to 20% by weight. In addition, various additives such as a rust preventive, a preservative, and a defoaming agent can be added to the above aqueous emulsion, if necessary.

The water-based resin (b) used in the water-based printing ink composition of the present invention is at least one selected from water-soluble or water-dispersible resins used in general inks, paints, recording agents and the like. The above resins can be mentioned, and a mixture of these resins may be used. Examples of the water-based resin (b) include polyurethane resin, polyurethane urea resin,
Acrylic-modified urethane resin, acrylic-modified urethane urea resin, acrylic resin, styrene-acrylic acid copolymer resin, styrene-maleic acid copolymer resin, ethylene-acrylic acid copolymer resin, polyester resin, shellac, rosin-modified maleic acid resin, chloride Examples thereof include vinyl-vinyl acetate copolymer resin, vinyl chloride-acrylic acid copolymer resin, chlorinated polypropylene resin, hydroxyethyl cellulose, hydroxypropyl cellulose, butyral and the like. These resins may be used alone or in combination of two or more. In particular, polyurethane resin, polyurethane urea resin, acrylic resin, and styrene-acrylic acid copolymer resin are preferable. The content of the aqueous resin (b) in the aqueous printing ink composition of the present invention is 4 to.
A proportion of 35% by weight is preferred.

In the water-based printing ink composition of the present invention, a neutralizing agent (pH adjusting agent) is used to increase the solubility of the resin. Examples include inorganic basic compounds such as caustic soda and caustic potash, ammonia, alkylamines such as methylamine, ethylamine, monoethanolamine, diethanolamine, triethanolamine, and organic basic compounds such as morpholine. These may be used alone or in combination of two or more. Inorganic basic compounds such as caustic soda and caustic potash, N, N
When a high-boiling organic basic compound such as -dibutylethanolamine or N-methyldiethanolamine is used, the water resistance of a printing ink coating film obtained by printing an aqueous printing ink composition may be poor, and therefore, for example, A volatile organic basic compound having a boiling point of 200 ° C. or less under 760 mmHg such as ammonia, triethylamine, morpholine, N-methylmorpholine, N-ethylmorpholine, N, N-dimethylethanolamine, N, N-diethylethanolamine. Preference is given to using.

The time of addition of the neutralizing agent in the present invention includes, for example, when the aqueous emulsion (a) is prepared, during the production of the aqueous printing ink composition, immediately before the printing operation, during the printing and the like. In both cases, the carboxylic acid (a) is neutralized (pH 7.0 to
9.5) to increase the solubility of the resin. The addition can be repeated as many times as necessary.

When a neutralizing agent is added to the aqueous emulsion (a), it is treated with a neutralizing agent to form a carboxylate group in a form in which some or all of the carboxyl groups are neutralized. Can also be emulsified. It is also possible to generate a carboxylate group in a form in which a part or all of the carboxyl groups are neutralized by performing the emulsification treatment in the presence of the neutralizing agent. When it is added during printing, the solubility of the resin decreases when the neutralizing agent in the aqueous printing ink composition is volatile such as ammonia during printing.

As the solvent used in the aqueous printing ink composition of the present invention, water, a water-miscible organic solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, ethylene glycol, ethylene glycol monomethyl ether, Ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether and the like can be used. These water and water-miscible organic solvents can be used alone or in admixture of two or more.

Further, the aqueous printing ink composition of the present invention comprises
Since it has a function required as an ink, it can contain a resin (binder), water, an organic solvent, a colorant and the like. In addition, extenders, pigment dispersants, leveling agents, defoamers, waxes, silane coupling agents, rust preventives, preservatives, plasticizers, infrared absorbers, ultraviolet absorbers, fragrances, flame retardants as required. It is also possible to add additives such as.

Examples of the colorant include organic and inorganic pigments and dyes used in general inks, paints, recording agents and the like. Examples of the organic pigment include azo-based, phthalocyanine-based, anthraquinone-based, perylene-based, perinone-based, quinacridone-based, thioindigo-based, dioxazine-based, isoindolinone-based, quinophthalone-based, azomethineazo-based, dictopyrrolopyrrole-based, isoindoline-based, and the like. Examples include pigments. It is preferable to use copper phthalocyanine in the indigo water-based printing ink composition from the viewpoint of coloring power. Examples of the inorganic pigment include carbon black, titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, silica, red iron oxide and the like. From the viewpoint of tinting strength, it is preferable to use titanium oxide for the white aqueous printing ink composition and carbon black for the black ink. Examples of the dye include azo-based, anthraquinone-based, perylene-based, perinone-based, and thioindigo-based pigments. These pigments and dyes may be used alone or in admixture of two or more for the purpose of adjusting hue and density. The pigment may be used in the form of an aqueous slurry, or the slurry may be powdered by drying such as spray drying. The pigment is preferably contained in an amount sufficient to secure the density and coloring power of the printing ink, that is, in a proportion of 1 to 50% by weight in the aqueous printing ink composition.

Examples of the leveling agent include acetylene diol, modified polysiloxane, fluorochemical surfactant, anionic surfactant, polyoxylen straight chain aliphatic alcohol, polyoxylen branched aliphatic alcohol, nonionic surfactant such as fat. Group alcohol alkylene oxide adducts, alkylphenol alkylene oxide adducts, aliphatic alkylene oxide adducts, higher alkylamine alkylene oxide adducts, aliphatic amide alkylene oxide adducts, sorbitol or sorbitan aliphatic ester, and the like, They can be used alone or in combination of two or more. Among the above, it is preferable to use the acetylene diol-based leveling agent from the viewpoint of the leveling property and the defoaming property.

As the defoaming agent, a silicone type defoaming agent, for example, an oil compound type defoaming agent in which a silicone oil such as dimethylpolysiloxane, methylphenylpolysiloxane, or methylvinylpolysiloxane is mixed with fine powder silica, and these oil compounds are used. An emulsion type antifoaming agent obtained by dispersing a surfactant in water together with a surfactant, a polyether type antifoaming agent such as stearyl alcohol, dipropylene glycol, glycerin and sorbitan.
Those obtained by adding alkylene oxide to polyhydric alcohol or those obtained by adding alkylene oxide to alkylphenol, or those obtained by esterifying these terminal hydroxyl groups, mineral oil-based defoaming agents, oil and fat defoaming agents, fatty acid defoaming agents, Examples thereof include a fatty acid ester-based defoaming agent, a higher alcohol-based defoaming agent, and a metal soap-based defoaming agent, which may be used alone or in combination of two or more.

The aqueous printing ink composition of the present invention comprises a carboxyl group-containing ethylene / α-olefin copolymer (a),
It can be produced by dissolving or dispersing the aqueous resin (b) as a binder, the essential components of the neutralizing agent, and other additives in a solvent. As an example, a pigment dispersion prepared by dispersing a pigment in a water-based resin (b) with a solvent, a carboxyl group-containing ethylene / α-olefin copolymer (a) water-based emulsion, a water-based resin (b), a neutralizing agent, It can be produced by adding additives such as a solvent, a leveling agent and an antifoaming agent. Alternatively, all the compounding ingredients can be added at the time of producing the above pigment dispersion.

The particle size distribution of the pigment in the pigment dispersion is determined by the size of the grinding media of the disperser, the packing ratio of the grinding media,
It can be adjusted by appropriately adjusting the dispersion treatment time, the ejection speed of the pigment dispersion, the viscosity of the pigment dispersion, and the like. As the disperser, for example, a roller mill, a ball mill, a pebble mill, an attritor, a sand mill or the like which is commonly used can be used. Further, when bubbles or unexpectedly large particles are contained in the aqueous printing ink composition, it is preferable to remove them by filtration or the like because the quality of the printed matter is deteriorated. A conventionally known filter can be used as the filter.

The viscosity of the printing ink composition of the present invention can be adjusted by appropriately selecting the type and amount of raw materials used, for example, the aqueous resin (b), pigment, water, organic solvent, basic compound and the like. You can When a pigment is used as the colorant, the viscosity of the aqueous printing ink composition can be adjusted by adjusting the particle size and particle size distribution of the pigment in the aqueous printing ink composition.

The viscosity of the aqueous printing ink composition of the present invention is
10 mPa · s or more from the viewpoint of preventing sedimentation of the pigment, and 10 from the viewpoint of workability during production of the aqueous printing ink composition or printing.
It is preferably 00 mPa · s or less. The viscosity in the present invention is a value obtained by a method using a rotational viscometer (BM type viscometer, measured at 25 ° C).

[0037]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples without departing from the technical idea of the present invention. In addition,
In the following description of the examples, the ink is an aqueous printing ink composition, parts are parts by weight, and the weight average molecular weight and number average molecular weight are values obtained in terms of polystyrene in gel permeation chromatography (GPC) measurement. The evaluation results are shown in Table 1.

<Synthesis Example 1> Grafting was carried out on 100 parts of an ethylene / propylene copolymer having an ethylene content of 50 mol%, a number average molecular weight of 810, and a Q value (weight average molecular weight / number average molecular weight) of 1.40. As a modifying component, 14 parts of maleic anhydride and 3.3 parts of ditertiary butyl peroxide were mixed, reacted at 160 ° C. for 4 hours under stirring, and then stirred under vacuum for 2 hours to give a pale yellow liquid. To give a maleic anhydride-modified ethylene / propylene copolymer (number average molecular weight: 810, Q value: 1.40). To 100 parts of the maleic anhydride-modified ethylene / propylene copolymer, 18 parts of morpholine were kneaded at 80 ° C, 82 parts of water was added, and the mixture was gently stirred at 80 ° C to give a solid content of 50% and a pale yellow transparent carboxyl. A group-containing ethylene / α-olefin copolymer aqueous emulsion (A) was obtained.

<Synthesis Example 2> 100 parts of a maleic anhydride-modified ethylene / propylene copolymer obtained by the same method as in Synthesis Example 1 was mixed with 100 parts of a 2N KOH aqueous solution, and the mixture was mixed with a homomixer at 80 ° C. Stirring under the condition of 12000 rpm, solid content 50%, milky white carboxyl group-containing ethylene / α-olefin copolymer aqueous emulsion (B)
Got

<Synthesis Example 3> Four-port 2000 m equipped with a reflux condenser, a dropping funnel, a gas inlet tube, a stirrer and a thermometer.
1 average molecular weight of 2,000 (hydroxyl value 55.
8) Polytetramethylene glycol 111.0 parts, average molecular weight 2,000 (hydroxyl value 56.3) polyethylene glycol 10.7 parts, 1,4 cyclohexanedimethanol 4.3 parts, dimethylolbutanoic acid 23.4. Parts, dibutyltin dilaurate 0.1 parts, methyl ethyl ketone 2
00 parts were charged, the atmosphere was replaced with dry nitrogen, and the temperature was raised to 80 ° C. With stirring, 80.4 parts of isophorone diisocyanate was added dropwise over 20 minutes and reacted for 3 hours. The reaction was cooled to 40 ° C. and N, N-bis (aminopropyl) methylamine 1
A mixture of 2.6 parts, 7.7 parts of isophoronediamine, and 100 parts of methyl ethyl ketone was added dropwise over 30 minutes, and further reacted at the same temperature for 1 hour to extend the chain. 88 water next
0 parts and 9.6 parts of aqueous ammonia were added and the temperature was raised to 4
Remove 30 parts of solvent and adjust to a solid content of 25%.
An aqueous urethane urea resin (C) having a weight average molecular weight of 38,700 was obtained.

<Synthesis Example 4> In a four-necked 2000 ml flask equipped with a reflux condenser, a dropping funnel, a stirrer, and a thermometer, the product name "John Cryl 679" (styrene-acrylic acid copolymer manufactured by Johnson Polymer Co., Ltd.) was used. Resin) 30.0
Part, 28% ammonia water 6.5 parts, and water 63.5 parts were charged, the temperature was raised to 60 ° C., and the mixture was stirred for 3 hours to completely dissolve the resin, and the solid content was 25% aqueous styrene-acrylic acid. A copolymer resin (D) (weight average molecular weight 8,000) was obtained.

[Example 1] A mixture having the following composition was kneaded with a sand mill to produce an aqueous printing ink composition of the present invention. -Titanium oxide 35.0 parts-Aqueous urethane urea resin (C) of Synthesis Example 3 45.0 parts-Water 11.8 parts-Isopropyl alcohol 3.0 parts-28% ammonia water 0.2 parts-Synthesis Example 1 Aqueous emulsion (A) 5.0 parts Total 100.0 parts

Water was added to 100 parts of the printing ink composition.
A mixed solvent of / isopropyl alcohol = 1/1 was added and the viscosity was adjusted to 16 seconds with Zan Cup # 3 manufactured by Riaisha Co., Ltd., a gravure plate with a plate depth of 25 μm, and a blade edge thickness of 6
A gravure rotary printing machine equipped with a 5μ doctor blade product name "New Doctor High Blade" (manufactured by Fuji Shoko Co., Ltd., hereinafter abbreviated as doctor blade), 100m /
After spinning at a cylinder rotation speed of 60 minutes for 60 minutes, a corona discharge-treated polyester film having a thickness of 12 μm “Ester film E5100” (manufactured by Toyobo Co., Ltd.)
Printing on the corona discharge treated surface of at a printing speed of 100 m / min,
A film printed with a printing ink composition (hereinafter abbreviated as a printing film) and a printing ink composition dried at 60 ° C. at a cylinder rotation speed of 100 m / min.
A doctor blade (hereinafter abbreviated as a doctor blade after a slip test) after being idle for a minute was obtained.

The plate fog resistance, blocking resistance, water resistance of the printing film, and the amount of wear of the doctor blade after the idling test were evaluated as shown below. Plate fogging property: A printing film was stuck on a black paper, and the amount of ink adhering to a blank portion (non-image area) was visually evaluated according to the following criteria. 5: No ink transfer was observed in the non-image area. 4: Slight ink transfer was observed in the non-image area. 3: Ink transfer was observed in a small area of the non-image area. 2: Ink transfer was observed in a large area of the non-image area. 1: Ink transfer was observed on the entire non-image area.

Doctor blade wear amount; manufactured by Sony Corporation
micro scope VMS-3000 and Meishin Koki's video mi
Using the cro scaler VMS-21, measure the blade length of the doctor blade. The value (μm) obtained by subtracting the blade length of the doctor blade after the idling test from the blade length of the doctor blade before use was defined as the doctor blade wear amount.

Blocking resistance: The printed surface and the non-printed surface of the printing film are overlapped with each other, and the load is 1 × 9.8 N / c.
After storing for 24 hours at m ² , 40 ° C. and relative humidity of 80%, it was peeled off and evaluated according to the following criteria. 5: There was no peeling resistance and no ink transfer was observed. 4: There was peeling resistance, but no ink transfer was observed. 3: A small area of ink was removed. 2: Blocking occurred in a large area. 1: Blocking occurred on the entire surface.

Water resistance: The print film was lightly rubbed with water-containing absorbent cotton 10 times and visually evaluated according to the following criteria. No peeling or dissolution of the ink surface was observed even after rubbing 5:10 times. 4: The ink surface peeled off and dissolved in about half the area. 3: Most of the ink surface was peeled off and dissolved. When rubbed 2: 5 times, most of the ink surface was peeled off and dissolved. Most of the ink surface was peeled off and dissolved when rubbed 1: 2 times.

Example 2 In the raw material of the printing ink composition of Example 1, 5.0 parts of the aqueous emulsion (B) of Synthesis Example 2 was used in place of the aqueous emulsion (A) of Synthesis Example 1. A white printing ink composition and a printing film were obtained and evaluated in the same manner as in 1.

Example 3 By the same method as in Example 1, a cyan printing ink composition was prepared from the following raw material compositions. -Copper phthalocyanine blue 5.0 parts-Aqueous urethane urea resin (C) of Synthesis Example 3 65.0 parts-Water 11.8 parts-Isopropyl alcohol 3.0 parts-28% ammonia water 0.2 parts-Synthesis Example 1 Aqueous emulsion (A) 5.0 parts Total 100.0 parts

Example 4 Among the raw materials for the printing ink composition of Example 1, the water-based urethane urea resin (C) of Synthesis Example 3 was used.
In place of the above, 45.0 parts of the aqueous styrene-acrylic acid copolymer resin (D) of Synthesis Example 4 was used, and a white printing ink composition and a printing film were obtained and evaluated in the same manner as in Example 1.

[Example 5] In the raw material of the printing ink composition of Example 1, instead of the water-based urethane urea resin (C) of Synthesis Example 3, "WEM141M" (acryl-modified urethane urea manufactured by Taisei Kako Co., Ltd.) was used. Resin, solid content approx. 35%) 4
Using 5.0 parts, a white printing ink composition and a printing film were obtained and evaluated in the same manner as in Example 1.

[Example 6] In the raw material of the printing ink composition of Example 1, the aqueous emulsion (A) of Synthesis Example 1 was added to 16.
Using 8 parts and 0 part of water, a white printing ink composition and a printing film were obtained and evaluated in the same manner as in Example 1.

Example 7 In the raw materials for the printing ink composition of Example 1, 1.0% of the aqueous emulsion (A) of Synthesis Example 1 was used.
Parts and water to 15.8 parts and white printing ink composition and printing film were obtained and evaluated in the same manner as in Example 1.

(Comparative Example 1) In the same manner as in Example 1, except that the aqueous emulsion (A) of Synthesis Example 1 was not used in the raw material of the printing ink composition of Example 1 and 16.8 parts of water was used. The printing ink composition and the printing film of were obtained and evaluated.

Comparative Example 2 In the same manner as in Example 1, except that the aqueous emulsion (A) of Synthesis Example 1 was not used in the raw material of the printing ink composition of Example 3 and water was 16.8 parts. Colored printing ink compositions and printing films were obtained and evaluated.

(Comparative Example 3) In the same manner as in Example 1, except that the aqueous emulsion (A) of Synthesis Example 1 was not used in the raw material of the printing ink composition of Example 4, and 16.8 parts of water was used. The printing ink composition and the printing film of were obtained and evaluated.

(Comparative Example 4) In the raw material of the printing ink composition of Example 5, the aqueous emulsion (A) of Synthesis Example 1 was not used, and 16.8 parts of water was used. The printing ink composition and the printing film of were obtained and evaluated.

[0058]

[Table 1]

[0059]

Since the water-based printing ink composition of the present invention has better lubricity than the conventional water-based printing ink composition, it has an effect of reducing wear of doctor blades, cylinders and anilox rolls. Therefore, the lifespan of these is greatly extended compared to the conventional case, and printing defects due to printing density reduction due to plate fogging and cylinder and anilox roll wear due to doctor blade wear can be greatly reduced, and work efficiency and economy are provided. Furthermore, a beautiful printed matter can be obtained at the time of printing, and its industrial value is extremely large.

Claims (5)

[Claims] 1. An aqueous printing ink composition comprising a carboxyl group-containing ethylene / α-olefin copolymer (a), an aqueous resin (b) and a neutralizing agent. 2. A carboxyl group-containing ethylene / α-olefin copolymer (a) comprising ethylene and an α-olefin, one or more kinds selected from unsaturated carboxylic acids or their anhydrides. Item 2. The water-based printing ink composition according to item 1. 3. The aqueous printing ink composition according to claim 1, wherein the content of the carboxyl group-containing ethylene / α-olefin copolymer (a) is in the range of 0.1 to 20% by weight. object. 4. The water-based printing ink composition according to claim 1, wherein the neutralizing agent is a volatile organic basic compound. 5. A printing method comprising using the aqueous printing ink composition according to claim 1.