JPH07292304A - Activating energy ray curing type printing ink - Google Patents

Abstract

PURPOSE:To obtain the subject printing ink, excellent in curability by activating energy rays and adhesiveness to a substrate, surface smoothness and recoatability. CONSTITUTION:The characteristic of this activating energy ray curing type printing ink comprises containing (A) a urethane acrylate, obtained by reacting the following components (1)-(3), having >=2 number of the repeating units in the component (1), containing 3-11 urethane binding groups and/or urea binding groups based on the constituent units of the component (1) and having 1000-20000 molecular weight, (B) a polymerizable monomer having <500 molecular weight and (C) a pigment: (1) a copolyester polyol, containing >=40mol% aromatic dicarboxylic acid and having 1000-10000 molecular weight, (2) a polyisocyanate compound and (3) a compound having >=1 (meth)acryloyloxy groups and >=1 hydrogen groups.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable printing ink which has good curability with respect to active energy rays and is excellent in adhesion to metals and plastics, surface smoothness and recoatability.

[0002]

2. Description of the Prior Art Active energy ray-curable printing inks are
Unlike general solvent-based ink, solvent-free and active energy ray curing process is highly productive, resource saving and energy saving. Due to these characteristics, application development is progressing as an ink for various base materials. However, the active energy ray-curable ink has poor wettability to the substrate,
Internal stress due to shrinkage during curing remains, resulting in poor adhesion to the substrate. In addition, multicolor printing has been widely used due to the high design of printing, but the conventional active energy ray-curable printing ink has insufficient adhesion to the base ink during overcoating, which hinders the development of applications. Was there.

[0003]

SUMMARY OF THE INVENTION The present invention was devised to solve the above-mentioned drawbacks of the prior art. The object of the present invention is to provide excellent curability for low energy active energy rays, and An object of the present invention is to provide an active energy ray-curable printing ink having excellent adhesion to plastics, surface smoothness, and recoatability.

[0004]

Means for Solving the Problems As a result of intensive studies for achieving the above object, the present inventors have found that a polyester polyol having a molecular weight of 1,000 to 20,000 obtained by copolymerizing a specific amount of an aromatic dicarboxylic acid with (2) A urethane acrylate having a specific range of molecular weight and urethane or urea group concentration obtained by introducing a compound having (3) one or more (meth) acryloyloxy groups and one or more hydrogen groups via an isocyanate compound ( A), polymerizable monomer (B)
When the printing ink obtained by blending the pigment and the pigment (C) is used, the active energy ray-curable printing ink is excellent in curability and adhesion to active energy rays at low energy, surface smoothness, and recoatability. I found that

That is, the active energy ray-curable printing ink of the present invention has two or more repeating units of the component (1) obtained by reacting with the following (1) to (3) and contains the component (1). A urethane acrylate (A) having a molecular weight of 1,000 to 20,000 having 3 to 11 urethane bonding groups and / or a urea bonding group per structural unit, a polymerizable monomer (B) having a molecular weight of less than 500, and a pigment (C). It is an active energy ray-curable printing ink characterized by containing it. (1) Copolyester polyol containing 40 mol% or more of aromatic dicarboxylic acid and having a molecular weight of 1,000 to 10,000 (2) Polyisocyanate compound (3) One or more (meth) acryloyloxy groups and one or more Compounds with hydrogen groups

The (1) copolymerized polyester polyol used in the present invention comprises a dicarboxylic acid component and a glycol component. The aromatic dicarboxylic acid which is an essential component in the present invention is a dicarboxylic acid having a group having aromaticity in the molecule, and examples thereof include phthalic anhydride, terephthalic acid, isophthalic acid, orthophthalic acid and 1,5-naphthalic acid. Is a typical example. If necessary, a small amount of tri- and tetracarboxylic acids such as trimellitic acid, trimesic acid and pyromellitic acid may be contained. Examples of the dicarboxylic acid copolymerizable with other than the aromatic dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid and other aliphatic dicarboxylic acids, 1,2-hexahydrophthalic acid, 1,3- Hexahydrophthalic acid,
Aliphatic dicarboxylic acids such as 1,4-hexahydrophthalic acid and perhydronaphthalene dicarboxylic acid, unsaturated dicarboxylic acids such as fumaric acid, maleic acid and itaconic acid, unsaturated fats such as tetrahydrophthalic acid and cyclobutene dicarboxylic acid Examples thereof include oxy acids such as cyclic dicarboxylic acid, p-hydroxyethyloxybenzoic acid and ε-caprolactone.

Examples of the glycol component include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol and 1,9-nonanediol. , Neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-cyclohexanedimethanol, spiroglycol, 1,4-phenylene glycol, 1,4-phenylene glycol Ethylene oxide adduct, bisphenol A ethylene oxide adduct and propylene oxide adduct, hydrogenated bisphenol A ethylene oxide adduct and propylene oxide adduct, polyethylene glycol,
Examples include diols such as polypropylene glycol and polytetramethylene glycol. If necessary, a small amount of trimethylolethane, trimethylolpropane, glycerin, pentaerythritol and other triols and tetraols may be contained.

In order to obtain a copolymerized polyester polyol from such a dicarboxylic acid component and a glycol component, the glycol raw material may be used in excess with respect to the dicarboxylic acid raw material. It is desirable to synthesize such that the carboxyl group end is less than 50 eq / 10 ⁶ g in the copolyester. When it is 50 eq / 10 ⁶ g or more, the number of inactive terminals in the reaction with the diisocyanate compound becomes too large when synthesizing the urethane acrylate resin described later, the desired urethane resin cannot be obtained, and the curability to active energy rays decreases. To do.

The polyester polyol used in the present invention contains 40 mol% or more of an aromatic dicarboxylic acid as a dicarboxylic acid component and has a molecular weight of 1,000 to 10,000. If the aromatic dicarboxylic acid component is less than 40 mol% as the dicarboxylic acid component, the adhesion is lowered and the toughness of the cured coating film is also lowered, which is not preferable. Further, if the molecular weight is less than 1000, the adhesiveness is reduced and the flexibility of the cured coating film is insufficient. If the molecular weight exceeds 10,000, the urethane-forming reactivity decreases and the viscosity increases, which causes a handling problem.

The (2) polyisocyanate compound used in the present invention is 2,4-tolylene diisocyanate,
2,6-tolylene diisocyanate, p-phenylene diisocyanate, biphenylmethane diisocyanate,
m-phenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, 3,
3'-dimethoxy-4,4'-biphenylene diisocyanate, 2,4-naphthalene diisocyanate, 3,
3'-dimethyl-4,4'-biphenylene diisocyanate, 4,4'-diphenylene diisocyanate, 4,
4'-diisocyanate diphenyl ether, 1,5 '
-Naphthalene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 1,3
-Diisocyanate compounds such as diisocyanate methylcyclohexane, 1,4-diisocyanate dicyclohexane, 4,4'-diisocyanate dicyclohexane, 4,4'-diisocyanate dicyclohexylmethane and isophorone diisocyanate, or 7 mol% or less of all isocyanate groups of 2 , 4-Tolylene diisocyanate trimer, hexamethylene diisocyanate 3
Triisocyanate compounds such as monomers may be mentioned. Of these isocyanate compounds, isophorone diisocyanate and hexamethylene diisocyanate are particularly preferable in terms of weather resistance.

The compound (3) having at least one (meth) acryloyloxy group and at least one hydrogen group used in the present invention is a mono (meth) glycol such as ethylene glycol, diethylene glycol or hexamethylene glycol. ) Acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, trimethylolpropane, glycerin, monomethyl triol compounds such as trimethylolethane ( Mono (meth) acrylates of tetravalent or higher valent polyols such as (meth) acrylate and di (meth) acrylate, pentaerythritol, dipentaerythritol,
Di (meth) acrylate, tri (meth) acrylate,
Examples thereof include hydroxyl group-containing acrylic compounds such as glycerin monoallyl ether and glycerin diacryl ether.

Urethane acrylate used in the present invention
(A) may optionally contain a polyol other than (1) and /
Alternatively, polyamines may be used as chain extenders. Examples of the polyol other than the above (1) include glycol components of the above (1) copolymerized polyester polyol such as ethylene glycol and propylene glycol. Examples of polyamines include hexamethylenediamine, diaminodiphenylmethane, N-methyldiethanolamine, and high molecular weight polyamines such as terminal aminated polybutadiene having two or more primary or secondary amino groups in the molecule. Further, water may be used similarly to these compounds.

The urethane acrylate (A) of the present invention is prepared by reacting the above-mentioned (1) copolymerized polyester polyol and (2) polyisocyanate compound at [NCO] / [OH] <2 to obtain an isocyanate-terminated urethane prepolymer. Then (3) one or more (meth) acryloyloxy groups and 1
It can be obtained by reacting a compound having at least one hydrogen group. As another production method, the above (1) copolymerized polyester polyol and (2) polyisocyanate compound are used in [NC
O] / [OH] ≧ 2 to obtain an isocyanate-terminated prepolymer, and then (3) a compound having at least one (meth) acryloyloxy group and at least one hydrogen group.
(4) It can be obtained by reacting a polyol and / or a polyamine other than the above (1). These resins can also be obtained by a method in which the compounds to be reacted are collectively charged at a fixed ratio and reacted.

The urethane acrylate (A) of the present invention thus obtained has a molecular weight in the range of 1,000 to 20,000, the number of repeating units of the component (1) is 2 or more in the molecule, and the number of repeating units of the component (1) is less than that of the component (1). It is necessary to have 3 to 11 urethane bonding groups and / or urea bonding groups per structural unit. When the molecular weight is less than 1000, the strain during curing becomes large, and the adhesion to the substrate becomes poor, which is not preferable. If the molecular weight exceeds 20,000, the compatibility with the polymerizable monomer (B) described later becomes poor, resulting in a problem that the viscosity becomes too high and it becomes difficult to use. When the number of repeating units is one, the toughness and adhesion of the coating film are insufficient. Even if the number of repeating units is 2 or more, if the number of urethane bonding groups and / or urea bonding groups in the molecule is less than 3 per unit of the constituent polyester polyol (1), the adhesion to the substrate will be insufficient. In addition, the toughness of the coating film is insufficient. If it exceeds 11, the adhesiveness will decrease and the viscosity will increase due to urethane bonds and the like, which is not preferable.

Another essential component of the present invention has a molecular weight of 50.
Examples of the polymerizable monomer (B) of less than 0 include (meth)
Methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate,
Phenoxyethyl (meth) acrylate, toluyloxyethyl (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, glycidyl (meth) acrylate , N, N-diethylaminoethyl (meth) acrylate, isobornyl (meth) acrylate, morpholinoethyl acrylate, ethylene oxide modified phosphoric acid (meth) acrylate, N-methylvinylpyrrolidone,
Caprolactone-modified tetrahydrofurfuryl (meth) acrylate, (meth) acryloxyethyl succinate, 2-hydroxy-3-phenoxypropyl (meth)
Monoacrylate compounds such as acrylate, ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol (meth) acrylate, diethylene glycol (meth) acrylate, tripropylene glycol di (meth) acrylate, Hydroxypivalic acid neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, bisphenol A di (meth) acrylate, ethylene oxide modified phosphoric acid di (meth) acrylate, ethylene oxide modified bisphenol A di (meth) ) Acrylate, diacrylate compounds such as polyethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol Tri (meth) acrylate,
Triacrylate compounds such as propylene oxide-modified trimethylolpropane triacrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, tetraacrylate compounds such as propionic acid-modified dipentaerythritol tetra (meth) acrylate, dimethylacrylamide , Isopropyl acrylamide, acryloyl morpholine, dimethylaminopropyl acrylamide and the like.

Among these polymerizable monomers, tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, toluyloxyethyl (meth) acrylate, N-vinylpyrrolidone, (meth) are preferred because of their excellent adhesion to polyethylene terephthalate. Acryloyl monophorine is preferred.

The pigment (C) used in the present invention is an inorganic type,
Any organic type can be used. Examples of inorganic pigments include titanium oxide and carbon black, and examples of organic pigments include phthalocyanine blue, quinacridone red, dioxadio violet, isoindoline yellow, and perylene maroon.

Active energy ray-curable printing inks using these compounds are curable to active energy rays, adherence to metals and plastics, especially polyethylene terephthalate, boiling water resistance, solvent resistance, weather resistance, and surface smoothness. And excellent coatability, which is preferable.

The active energy ray-curable printing ink of the present invention comprises the above urethane acrylate (A) and a polymerizable monomer.
It is a mixture of (B) and pigment (C). The mixing ratio can be set arbitrarily, but the weight ratio is (A) / (B) /
The range of (C) = 20 to 50/10 to 50/5 to 55 is preferable. When the content of the component (A) is less than 20% by weight, the properties of the urethane acrylate resin are lost, the adhesion to metals and plastics is deteriorated, the solvent resistance, the weather resistance and the recoatability are deteriorated, which is not preferable. On the other hand, when the content of the component (A) exceeds 50% by weight, the viscosity becomes too high to make it difficult to use, and not only the surface smoothness is deteriorated but also the curability to active energy rays is deteriorated, which is not preferable.

As a method of producing the active energy ray-curable printing ink of the present invention, there is a method of blending the polymerizable monomer (B) after synthesizing the urethane acrylate (A) by the above method. Alternatively, the polymerizable monomer
There is a method of synthesizing urethane acrylate (A) using (B) as a reaction solvent. As a method for blending the pigment (C), it is preferable to add the pigment (C) to the urethane acrylate resin (A) and disperse it, but the method is not limited to this method.

Components other than the above-mentioned components (A) to (C) can be added to the active energy-curable printing ink of the present invention, if necessary. The components that can be added are not particularly limited as long as they are used in ordinary printing inks. For example, other resins, plasticizers, defoamers, leveling agents, solvents,
There are stabilizers, photopolymerization initiators and the like. In particular, active energy used in the present invention The active energy rays used in the present invention are ultraviolet rays, electron rays, γ rays, neutron rays and the like.
When ultraviolet rays are used, it is desirable to add a photopolymerization initiator to the active energy ray-curable printing ink.

The organic solvent usable in the present invention is limited to volatile ones, and most or all of them must be volatilized by heating and drying before curing with active energy rays. Examples of usable solvents include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, esters such as methyl acetate and ethyl acetate, ethers such as tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, benzene, toluene, xylene, and the like. , Aromatic hydrocarbons such as hexane and heptane, alcohols such as methanol, ethanol and isopropyl alcohol, and mixtures thereof. The solvent used during the synthesis of the urethane acrylate resin (A) of the present invention can be used as it is.

As the photopolymerization initiator, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 1
-(4-Isopropylphenyl) -2-hydroxy-2
-Methylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl)
Acetophenones such as ketones, 1-hydroxycyclohexyl-phenyl ketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl Benzoin ethers such as ether, benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, 4-
Benzoyl-4′-methyl-diphenyl sulfide,
Alkylated benzophenone, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 4-benzoyl-N, N-dimethyl-N- [2-
((1-Oxo-2-propenyloxy) ethyl] benzenemethanaminium bromide, benzophenones such as (4-benzoylbenzyl) trimethylammonium choroid, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethyl Examples thereof include thioxanthones such as thioxanthone and 2,4-dichlorothioxanthone, which may be used alone or in combination.

Further, as the photopolymerization initiator, triethanolamine, methyldiethanolamine, triethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, benzoic acid (2 -Dimethylamino) ethyl,
4,4'-Dimethylaminobenzophenone, 4,4'-
A sensitizer such as diethylaminobenzophenone may be used in combination.

As an electron beam irradiator, a scanning system,
Or the curtain beam method can be adopted, and the absorbed dose is 1
-20 Mrad, preferably 2-15 Mrad.

The active energy ray-curable printing ink of the present invention is characterized by excellent curability against active energy rays, adhesion to metals and plastics, surface smoothness, recoatability, boiling water resistance, and weather resistance. Alive
Various materials can be printed using methods such as silk screen, offset, gravure and flexo.

[0027]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. In the examples, "parts" means "parts by weight".

(Production Example of Copolyester Polyol) Dimethyl terephthalate 44 was placed in a reaction vessel equipped with a thermometer, a stirrer, a distillation column, a condenser, and a pressure reducing device.
0 part, 440 parts of dimethyl isophthalate, 412 parts of ethylene glycol, 393 parts of hexanediol, and 0.5 parts of tetrabutoxy titanate were charged, and 150 to 23
A transesterification reaction was performed by heating at 0 ° C for 120 minutes.
Then, the reaction system was depressurized to 10 mmHg and the temperature was raised to 250 ° C. for 30 minutes to carry out the reaction to obtain a copolymerized polyester polyol A. Polyester polyol A has a molecular weight of 160
It was 0. The polyester polyols B to F obtained by the same method are shown in Table 1 together with the polyester polyol A. The resin composition was analyzed by ¹ H NMR.

[0029]

[Table 1]

(Production Example 1 of active energy ray-curable resin composition) 100 parts of copolymerized polyester polyol A and 132 parts of phenoxyethyl acrylate were charged into a reaction vessel equipped with a thermometer, a stirrer and a reflux condenser, and after dissolution,
After charging 17 parts of hexamethylene diisocyanate and 0.05 parts of dibutyltin dilaurate and reacting them at 70 to 80 ° C. for 2 hours, 15 parts of 2-hydroxyethyl acrylate is further added and the reaction is carried out at 70 to 80 ° C. An active energy ray-curable resin composition A which was a phenoxyethyl acrylate solution of a urethane acrylate resin was obtained. The molecular weight of urethane acrylate is 2000
Met. Urethane acrylate resins were synthesized by the same method to obtain active energy ray-curable resin compositions B to E. The composition obtained is shown in Table 2.

[0031]

[Table 2]

(Production Example 2 of active energy ray-curable resin composition) 100 parts of copolymerized polyester polyol A and 135 parts of acryloyl morpholine were placed in a reaction vessel equipped with a thermometer, a stirrer and a reflux condenser, and after dissolution, hexa After charging 21 parts of methylene diisocyanate and 0.05 parts of dibutyltin dilaurate and reacting at 70 to 80 ° C. for 2 hours, 2-hydroxyethyl acrylate 7 was further added.
Parts and reacting at 70 to 80 ° C. for further 2 hours, and then adding 7 parts of 3-methyl-1,5-pentanediol as a chain extender to carry out the reaction to obtain an acryloylmorpholine solution of urethane acrylate resin. An energy ray curable resin composition F was obtained. The molecular weight of urethane acrylate was 4,100. Urethane acrylate resins were synthesized by the same method to obtain active energy ray-curable resin compositions G to K. The composition obtained is shown in Table 3.

[0033]

[Table 3]

Example 1 A photopolymerization initiator 1- (4-isopropylphenyl) -2-based on 100 parts of the active energy ray-curable resin composition B.
Hydroxy-2-methylpropan-1-one (manufactured by Darocur 1116 MARK) 8 parts, titanium oxide (CR
-930 Ishihara Sangyo Co., Ltd., 100 parts, 3 parts of a defoaming agent and 4 parts of a leveling agent were mixed with a tabletop coater, and applied on a polyethylene terephthalate sheet using a 250 mesh screen. Then, ultraviolet rays were radiated to 400 mJ / cm ² with a 6.4 kw × 4 lamp water-cooled low-pressure mercury lamp to carry out polymerization and curing. In addition, ink was similarly applied and cured so that a part of the cured film was overlapped. A hardened film was formed on a galvanized steel sheet, a polycarbonate sheet, a polyethylene sheet, and a vinyl chloride sheet according to the above method. Printing inks were similarly prepared from the resin compositions C, E, F and H to obtain a cured film.

Comparative Example 1 A photopolymerization initiator 1- (4-isopropylphenyl) -2-based on 100 parts of the active energy ray-curable resin composition A.
Hydroxy-2-methylpropan-1-one (manufactured by Darocur 1116 MARK) 8 parts, titanium oxide (CR
-930 Ishihara Sangyo Co., Ltd., 100 parts, 3 parts of a defoaming agent and 4 parts of a leveling agent were mixed with a tabletop coater, and applied on a polyethylene terephthalate sheet using a 250 mesh screen. Then, ultraviolet rays were radiated to 400 mJ / cm ² with a 6.4 kw × 4 lamp water-cooled low-pressure mercury lamp to carry out polymerization and curing. Further, ink was similarly applied and cured so that a part of the cured film overlapped.
A hardened film was formed on a galvanized steel sheet, a polycarbonate sheet, a polyethylene sheet, and a vinyl chloride sheet according to the above method. Printing inks were similarly prepared from the resin compositions D, G, I, J, and K to obtain a cured film.

The cured film was evaluated by the following method. -Adhesion: Using a ruler for cross-cutting test of Taiki Equipment Co., Ltd., 100 cross-cuts of 1 mm x 1 mm were made on the coating film with a cutter knife, and Nichiban Co., Ltd. cellophane tape No. 405 was attached and peeled off, and the number of crosses in which the coating film was adhered without peeling off was evaluated.

Overcoating Property An ink was further applied onto the cured ink film, and the cured portion was used to perform an adhesion evaluation test between the upper layer ink and the lower layer ink by the above method.

-Solvent resistance The surface of the cured film is treated with gauze containing ethanol to give 50
The surface condition after rubbing was observed. ○: No abnormality △: Scratched ×: The coating film peels off

-Boiling water resistance After the cured film was immersed in boiling water, it was boiled for 2 hours, and the surface condition of the film was visually judged. ◯: No abnormality Δ: Slightly cloudy or slightly peeled off ×: Severly clouded or peeled coating film

Weather resistance In the accelerated weather resistance test (QUV), the change in gloss after 300 hours of exposure was visually judged. ◯: No abnormality Δ: Gloss slightly decreased X: Gloss significantly decreased

Tables 4 and 5 show the evaluation results of the cured coatings of the active energy ray-curable printing inks of Example 1 and Comparative Example 1.

[0042]

[Table 4]

[0043]

[Table 5]

Example 2 30 parts of trimethylolpropane triacrylate, 100 parts of titanium dioxide and 1- (4-isopropylphenyl) -2-hydroxy-2 photoinitiator per 100 parts of active energy ray-curable resin composition B. -Methylpropan-1-one (Darocur 1116 MARK) 5
Parts and kneading with a three-roll mill, printing ink composition A
Was adjusted. This ink composition was printed on a polyethylene terephthalate film using a 200 mesh screen and a squeegee having a Shore A hardness of 80. Then, 6.4kw x 4 lights water-cooled low-pressure mercury lamp 300m UV light
Curing was performed by irradiating so as to be J / cm ² . Printing inks C, E, F, and H were similarly printed and cured.

Comparative Example 2 30 parts of trimethylolpropane triacrylate, 100 parts of titanium dioxide and 1- (4-isopropylphenyl) -2-hydroxy-2-photopolymerization initiator per 100 parts of active energy ray-curable printing ink A were used. Methylpropan-1-one (Darocur 1116 MERK) 5
Parts and kneading with a three-roll mill, printing ink composition A
Was adjusted. This ink composition was printed on a polyethylene terephthalate film using a 200 mesh screen and a squeegee having a Shore A hardness of 80. Then, 6.4kw x 4 lights water-cooled low-pressure mercury lamp 300m UV light
Curing was performed by irradiating so as to be J / cm ² . Printing inks D, G, I, J, and K were similarly printed and cured.

The cured ink film was evaluated by the following methods. -Adhesion property The same method as in Example 1 and Comparative Example 1 was used for evaluation. -Pencil hardness Tested according to the method described in JIS K5400.

Solvent resistance After the cured ink film was impregnated with 99% ethanol for 1 hour, the adhesion was evaluated. -Appearance The state of the coating film surface after curing was visually determined. ◯: Surface is smooth and glossy Δ: Surface gloss is low ×: Surface gloss is not

Table 6 shows the evaluation results of the cured coatings of the active energy ray-curable printing inks of Example 2 and Comparative Example 2.

[0049]

The active energy ray-curable printing ink of the present invention has excellent curability with respect to active energy rays, and the cured film has excellent adhesion to metals and plastics, surface smoothness, and recoatability. can get.

[Table 6]

Claims (1)

[Claims] 1. The number of repeating units of the component (1) obtained by reacting with the following (1) to (3) is 2 or more and the component (1):
Having a molecular weight of 3 to 11 urethane bond groups and / or urea bond groups per unit of 1000 to 2000
No. 0 urethane acrylate (A), a polymerizable monomer (B) having a molecular weight of less than 500, and a pigment (C) are contained. Active energy ray-curable printing ink (1) Aromatic dicarboxylic acid Copolymerized polyester polyol containing 40 mol% or more and having a molecular weight of 1,000 to 10,000 (2) Polyisocyanate compound (3) A compound having at least one (meth) acryloyloxy group and at least one hydrogen group.