JP5493424B2 - Active energy ray curable lithographic printing ink and printed matter thereof - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an active energy ray-curable lithographic printing ink and a printed material thereof, and relates to an active energy ray-curable lithographic printing ink and a printed material thereof that achieve both excellent printability and print film strength.

  The active energy ray-curable ink contains an unsaturated compound having active energy ray curability, such as an acrylic ester compound, as a constituent component. The active energy ray curable ink is instantly cured when irradiated with the active energy ray, and the unsaturated compound is three-dimensionally crosslinked. A tough film is formed by. Because it cures instantaneously, it can be post-processed immediately after printing, so active energy ray curing is required for packaging package printing and form printing in commercial fields where a strong coating is required to improve productivity and protect the design. Mold inks are preferably used. In addition, lithographic printing, which is advantageous in terms of printing quality, printing speed, and price, is often used.

  In general, an active energy ray-curable lithographic offset printing ink comprises a binder resin, an active energy ray-curable compound such as an acrylic ester compound, a pigment, a radical polymerization initiator, and various additives.

  The active energy ray curable lithographic printing ink is required to have printing suitability such as emulsification suitability, stain resistance, and curability. At the same time, printed film strength such as friction resistance, solvent resistance, and heat resistance is required. As active energy ray-curable binder resins, unsaturated polyester resins, epoxy acrylate resins, urethane acrylate resins, polyester acrylate resins, and the like have been studied. For example, Patent Document 1 discloses a resin obtained by modifying a saturated polyester with an isocyanate group-containing urethane acrylate. However, since these resins have a highly linear structure, it is difficult to obtain sufficient ink viscoelasticity, and the printing suitability such as misting property and background stain resistance is liable to be impaired. Patent Document 2 discloses a resin obtained by reacting a hydroxyl-excess polyester compound containing rosin derivative polyvalent carboxylic acid as an essential component with acrylic acid or methacrylic acid. However, rosin derivative polyvalent carboxylic acid is sufficiently specified. However, when the residual amount of the conjugated double bond is large, it is easy to cause curing inhibition, and the problem of insufficient curability and printed film strength tends to occur.

JP 2001-348516 A Japanese Patent Laid-Open No. 2-51516

  An object of the present invention is to provide an active energy ray-curable lithographic printing ink and a printed material thereof that have both printability and printed film strength.

  As a result of diligent research, the inventors have made an addition reaction between an α, β-unsaturated carboxylic acid and a resin acid, and then a resin obtained by reacting a polyhydric alcohol compound, thereby providing excellent printability and printed film strength. The inventors have found that an active energy ray-curable lithographic printing ink capable of satisfying both of the above can be obtained, and the present invention has been completed.

That is, the present invention relates to an active energy ray-curable lithographic printing ink containing (a) a resin, (b) an active energy ray-curable compound and (c) a pigment,
(A) A resin synthesized by reacting a resin acid with 80 to 100 mol% of an α, β-unsaturated carboxylic acid or anhydride based on the resin acid, and further reacting with a polyhydric alcohol The resin acid is 10 to 40% by weight in the total reaction compound (here, the total reaction compound is the total amount of the reaction compound in both the addition reaction and the reaction with the polyhydric alcohol). ),
(A) The resin is contained in an amount of 10 to 40% by weight of the total amount of the ink,
(B) the active energy ray-curable compound is contained in an amount of 30 to 75% by weight based on the total amount of the ink;
And (c) the pigment is 5 to 40% by weight of the total amount of the ink
The present invention relates to an active energy ray-curable lithographic printing ink characterized by being contained.

Furthermore, the present invention relates to the above active energy ray-curable lithographic printing ink, wherein the resin acid has a conjugated double bond.
The present invention also relates to the above active energy ray-curable lithographic printing ink, wherein the α, β-unsaturated carboxylic acid or the anhydride is maleic acid or the anhydride, respectively.

  Furthermore, the present invention relates to a printed matter obtained by printing the above active energy ray-curable lithographic printing ink on a substrate and curing it with active energy rays.

  The active energy ray-curable lithographic printing ink of the present invention enables printing with excellent printability such as curability and stain resistance, and can provide a printed matter with excellent printed film strength.

  The resin in which (a) an α, β-unsaturated carboxylic acid and a resin acid of the present invention are subjected to an addition reaction and then a polyhydric alcohol compound is reacted is as follows.

  The resin acid of the present invention is not particularly limited as long as it is an organic acid present as a free or ester contained in a natural resin. Examples include abietic acid, neoabietic acid, d-pimalic acid, iso-d-pimalic acid, podocarpic acid, agatendicarboxylic acid, danmarol acid, benzoic acid, cinnamic acid, p-oxycinnamic acid and the like. Use in the form of a natural resin containing these resin acids is preferable in terms of handling, and examples thereof include gum rosin, wood rosin, tall oil rosin, copal, and dammar. Furthermore, some can be disproportionated, dimerized and hydrogenated, but considering the reactivity with α, β-unsaturated carboxylic acid compounds, it contains conjugated double bonds such as abietic acid. It is desirable to contain 50% by weight or more of the compound.

  Further, α, β-unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, crotonic acid, isocrotonic acid, cinnamic acid, 2,4-hexadienic acid and the like. Anhydrides are exemplified. In view of the reactivity with the resin acid, maleic acid or its anhydride is preferred.

  The polyhydric alcohol compound in the present invention is not particularly limited as long as it is a compound having two or more hydroxyl groups in the molecule. For example, the dihydric alcohol is a 1,2-2-alkylene linear alcohol. Ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,6-hexane Diol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol 1,2-decanediol, 1,10-decanediol, 1,12-dodecanediol, 1,2-dodecanediol, 2-methyl-2,4-pentanediol, 3-methyl, wherein 14-tetradecanediol, 1,2-tetradecanediol, 1,16-hexadecanediol, 1,2-hexadecanediol, etc. are branched alkylene dihydric alcohols -1,5-pentanediol, 2-methyl-2-propyl-1,3-propanediol, 2,4-dimethyl-2,4-pentanediol, 2,2-diethyl-1,3-propanediol 2,2,4-trimethyl-1,3-pentanediol, dimethyloloctane, 2-ethyl-1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 2-methyl-1, 8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, 2,4-diethyl-1,5-pentanediol, etc. 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cycloheptanediol, tricyclodecane dimethanol, hydrogenated bisphenol A, and hydrogenated cyclic dihydric alcohol Bisphenol F, hydrogenated bisphenol S, hydrogenated catechol, hydrogenated resorcin, hydrogenated hydroquinone, polyethylene glycol (n = 2 to 20), polypropylene glycol (n = 2 to 20), polytetramethylene glycol (n = 2) Polyether polyols, polyester polyols and the like such as -20).

  Examples of the trihydric or higher polyhydric alcohol include glycerin, trimethylolpropane, pentaerythritol, 1,2,6-hexanetriol, 3-methylpentane-1,3,5-triol, hydroxymethylhexanediol, trimethyloloctane, Examples include linear, branched and cyclic polyhydric alcohols such as diglycerin, ditrimethylolpropane, dipentaerythritol, sorbitol, inositol and tripentaerythritol.

  The resin (a) of the present invention is obtained by an addition reaction between a resin acid and an α, β-unsaturated carboxylic acid and then a reaction with a polyhydric alcohol compound. The reaction includes Diels-Alder addition reaction between a conjugated double bond in a resin acid and a double bond in an α, β-unsaturated carboxylic acid, and multiple reactions with a carboxylic acid in a resin acid or α, β-unsaturated carboxylic acid. Two types of esterification reaction with a hydroxyl group in a monohydric alcohol compound can occur. Since the addition reaction product of a resin acid and an α, β-unsaturated carboxylic acid becomes a polyvalent carboxylic acid compound, it can be polymerized by an esterification reaction with a polyhydric alcohol compound. In addition, the conjugated double bond in the resin acid, which becomes a curing inhibition component when irradiated with active energy rays, disappears due to the addition reaction, and by introducing a polycyclic structure derived from the resin acid, printability such as emulsification characteristics, high-speed printability, and curability And film strength can be achieved at the same time. The addition reaction and esterification reaction may be performed simultaneously, or there is no problem even if either of them is performed first.

Diels-Alder addition reaction is suitably carried out at a temperature range of 120 ° C. to 250 DEG ° C.. 80 to 100 mol% of the conjugated double bond contained in the tree Aburasan is that is subjected to the reaction. If it is less than 50 mol%, curing inhibition due to a conjugated double bond tends to occur, and the molecular weight of the finally obtained (a) resin is hardly increased, which is not preferable.

  The esterification reaction can be performed according to a conventional method. Usually, it is carried out in the range of 150 ° C. to 300 ° C., but can be determined in consideration of the boiling point and reactivity of the compound used. In these reactions, a catalyst can be used as necessary. Catalysts include organic sulfonic acids such as benzenesulfonic acid, p-toluenesulfonic acid, p-dodecylbenzenesulfonic acid, methanesulfonic acid and ethanesulfonic acid, mineral acids such as sulfuric acid and hydrochloric acid, trifluoromethyl sulfuric acid, and trifluoromethylacetic acid. Etc. can be illustrated. Furthermore, metal complexes such as tetrabutyl zirconate and tetraisobutyl titanate, metal salt catalysts such as magnesium oxide, magnesium hydroxide, magnesium acetate, calcium oxide, calcium hydroxide, calcium acetate, zinc oxide, and zinc acetate can also be used. is there. These catalysts are usually used in the range of 0.01 to 5% by weight in the total resin. In order to suppress coloring of the resin due to the use of a catalyst, hypophosphorous acid, triphenyl phosphite, triphenyl phosphate, triphenylphosphine and the like can be used in combination.

  The resin (a) of the present invention can be obtained by reacting a monohydric alcohol compound and a carboxylic acid-containing compound other than the α, β-unsaturated carboxylic acid as necessary. Examples of monohydric alcohol compounds include linear alkyl monohydric alcohols such as 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-hexanol, 2-hexanol, 3-hexanol, 1-heptanol, 2- Heptanol, 3-heptanol, 1-octanol, 2-octanol, 3-octanol, 1-nonanol, 2-nonanol, 1-decanol, 2-decanol, 1-undecanol, 1-dodecanol, 2-dodecanol, 1-tridecanol, 1-tetradecanol, 2-tetradecanol, 1-pentadecanol, 1-hexadecanol, 2-hexadecanol, 1-heptadecanol, 1-octadecanol, 1-nonadecanol, 1-eicosanol, etc. Can be illustrated. Further, branched alkyl monohydric alcohols such as 2-propyl-1-pentanol, 2-ethyl-1-hexanol, 4-methyl-3-heptanol, 6-methyl-2-heptanol, 2,4,4-trimethyl- 1-pentanol, 3,5,5-trimethyl-1-hexanol, 2,6-dimethyl-4-heptanol, isononyl alcohol, 3,7-dimethyl-1-octanol, 2,4-dimethyl-1-heptanol , 2-heptylundecanol and the like. Examples of the cyclic alkyl monohydric alcohols such as cyclohexanol, cyclohexanemethanol, cyclopentanemethylol, dicyclohexylmethanol, tricyclodecane monomethylol, norbonol, water-added rosin alcohol (trade name: Abitol, manufactured by Hercules Co., Ltd.), etc. be able to.

  Examples of carboxylic acid-containing compounds other than the α, β-unsaturated carboxylic acid include monobasic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, Undecyl acid, lauric acid, tridecyl acid, myristic acid, pentadecylic acid, palmitic acid, heptadecyl acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid and other saturated fatty acids, isocrotonic acid, lindelic acid, tuzuic acid, myristoleic acid , Palmitoleic acid, undecylic acid, oleic acid, elaidic acid, gadoleic acid, gondrenic acid, cetreic acid, erucic acid, brassic acid, linoleic acid, linoelaidic acid, linolenic acid, eleostearic acid, arachidonic acid, iwacic acid, herring Unsaturated fatty acids such as acids, benzoic acid, methylbenzoic acid, tar Examples include aromatic monobasic acids such as shalybutylbenzoic acid, naphthoic acid, and orthobenzoylbenzoic acid. As the polybasic acid, alkenyl succinic acid such as oxalic acid, malonic acid, succinic acid, glutaric acid, pimelic acid, sebacic acid, azelaic acid, dodecenyl succinic acid, pentadecenyl succinic acid, etc. Phthalic acid, isophthalic acid, terephthalic acid, 1,2,3,6-tetrahydrophthalic acid, 3-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydro Phthalic acid, hexahydrophthalic acid, 3-methylhexahydrophthalic acid, 4-methylhexahydrophthalic acid, hymic acid, 3-methylhymic acid, 4-methylhymic acid, trimellitic acid, pyromellitic acid, etc. And their anhydrides. Furthermore, fatty acids of natural fats and oils such as tung oil fatty acid, linseed oil fatty acid, soybean oil fatty acid, coconut oil fatty acid, (dehydrated) castor oil fatty acid, palm oil fatty acid, safflower oil fatty acid, cottonseed oil fatty acid, rice bran oil fatty acid, olive oil fatty acid Rapeseed oil fatty acid and the like, and dimer acid of the fatty acid, such as tung oil dimer fatty acid, linseed oil dimer fatty acid and the like can also be used.

The resin (a) of the present invention is obtained by reaction with the resin acid, the α, β-unsaturated carboxylic acid and the polyhydric alcohol compound, and, if necessary, the monohydric alcohol compound and the carboxylic acid compound. The resin acid subjected to the reaction is in the range of 10 to 40% by weight in the total reaction compound. When the content is less than 10% by weight, it is not preferable because physical properties such as emulsification characteristics and film strength derived from the polycyclic structure of the resin acid are hardly exhibited. Moreover, when it exceeds 40 weight%, the solubility to (b) active energy ray hardening compound tends to be inferior, and is unpreferable. Furthermore, the total number of moles of carboxylic acid groups is preferably 0.5 to 2 with respect to the total number of moles of hydroxyl groups in terms of reaction control.

  The resin (a) obtained by the above reaction preferably has a weight average molecular weight of 3000 to 150,000 in terms of polystyrene measured by gel permeation chromatography (GPC), an acid value of 60 or less, and a melting point of 60 ° C. or more. Outside the above range, emulsification suitability, transferability, curability and the like when used as a printing ink are not preferred because they tend to be insufficient.

  The active energy ray-curable lithographic printing ink of the present invention comprises (a) an α, β-unsaturated carboxylic acid and a resin acid that are subjected to an addition reaction, and then 10 to 40 weights of a resin obtained by a reaction with a polyhydric alcohol compound. %, (B) 30 to 75% by weight of the active energy ray-curable compound, and (c) 5 to 40% by weight of the pigment.

  The (b) active energy ray-curable compound in the present invention is not particularly limited as long as it is a compound that is cured by irradiation with active energy rays such as ultraviolet rays and electron beams. Examples include compounds having a bond. Examples of the active energy ray-curable compound include monofunctional vinyl compounds such as styrene, 2-ethylhexyl (meth) acrylate, methoxydiethylene glycol (meth) acrylate, N-methylpyrrolidone, and acryloylmorpholine, ethylene glycol di (meth) acrylate, Polyethylene glycol di (meth) acrylate (n = 2 to 20), propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate (n = 2 to 20), alkane (carbon number 4 to 12) glycol di (meta) ) Acrylate, alkane (4 to 12 carbon atoms) glycol ethylene oxide adduct (2 to 20 mol) di (meth) acrylate, alkane (4 to 12 carbon atoms) glycol propylene oxide adduct (2 to 20 mol) di (Meth) acrylate, hydroxypivalylhydroxypivalate di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, bisphenol A ethylene oxide adduct (2 to 20 mol) di (meth) acrylate, hydrogenated bisphenol A di Bifunctional vinyl compounds such as (meth) acrylate, hydrogenated bisphenol A ethylene oxide adduct (2 to 20 mol) di (meth) acrylate, glycerin tri (meth) acrylate, glycerin ethylene oxide adduct (3 to 30 mol) tri (Meth) acrylate, glycerin propylene oxide adduct (3-30 mol) tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide adduct (3-30 mol) Trifunctional vinyl compounds such as tri (meth) acrylate, trimethylolpropane propylene oxide adduct (3-30 mol) tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol ethylene oxide adduct (4-40 mol) ) Tetra (meth) acrylate, pentaerythritol propylene oxide adduct (4-40 mol) tetra (meth) acrylate, diglycerin tetra (meth) acrylate, pentaerythritol ethylene oxide adduct (4-40 mol) tetra (meth) acrylate , Pentaerythritol propylene oxide adduct (4 to 40 mol) tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, ditrimethylolpropane ethylene oxide Tetrafunctional vinyl compounds such as xide adduct (4 to 40 mol) tetra (meth) acrylate, ditrimethylolpropane propylene oxide adduct (4 to 40 mol) tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, di Examples thereof include polyfunctional vinyl compounds such as pentaerythritol ethylene oxide adduct (6 to 60 mol) hexa (meth) acrylate and dipentaerythritol propylene oxide adduct (6 to 60 mol) hexa (meth) acrylate, and mixtures thereof. (B) The active energy ray-curable compound can be appropriately selected according to the required cured film properties, and an active energy ray-curable oligomer such as polyester acrylate, polyurethane acrylate, or epoxy acrylate, if necessary. It is also possible to use together.

Next, examples of the (c) pigment include inorganic pigments and organic pigments.
Examples of inorganic pigments include chrome yellow, zinc yellow, bitumen, barium sulfate, cadmium red, titanium oxide, zinc white, petal, alumina white, calcium carbonate, ultramarine, carbon black, graphite, aluminum powder, etc. Soluble azo pigments such as β-naphthol, β-oxynaphthoic acid, β-oxynaphthoic acid allylide, acetoacetate allylide, pyrazolone, etc., β-naphthol, β-oxynaphthoic acid allylide, aceto Insoluble azo pigments such as allyl acetate monoazo, allyl acetoacetate disazo, pyrazolone, phthalocyanine pigments such as copper phthalocyanine blue, halogenated (chlorinated or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, metal-free phthalocyanine, Quinacridone, dioxadi Polynes such as pyranthrone, anthanthrone, indanthrone, anthrapyrimidine, flavantron, thioindigo, anthraquinone, perinone, perylene, etc., isoindolinone, metal complex, quinophthalone, etc. Various publicly known pigments such as pigments and heterocyclic pigments can be used.

  When the active energy ray-curable lithographic printing ink of the present invention uses ultraviolet rays, it is necessary to add a photoinitiator. Photopolymerization initiators can be broadly classified into two types: those in which bonds are cleaved within the molecule by light to generate active species, and those in which hydrogen abstraction reactions occur between molecules to generate active species.

  Examples of the former include, for example, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, diethoxyacetophenone, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2 -Propyl) ketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-hydroxy-cyclohexyl-phenyl Ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, benzyldimethyl ketal, oligo {2-hydroxy-2-methyl-1- [ 4- (1-methylvinyl) phenyl] propane}, 4- (2-acryloyl-oxyethoxy) phenyl-2-hi Acetophenones such as loxy-2-propyl ketone, benzoins such as benzoin, benzoin isopropyl ether, benzoin isobutyl ether, mixtures of 1-hydroxycyclohexyl-phenyl ketone and benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide Acylphosphine oxides such as bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, benzyl, methylphenylglyoxyester, 3,3 ′, 4,4′-tetra (t-butylperoxy) Carbonyl) benzophenone and the like.

  Examples of the latter include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4,4′-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4′-methyl-diphenyl sulfide, acrylated benzophenone, 3,3 Benzophenones such as', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4- Thioxanthones such as diethylthioxanthone and 2,4-dichlorothioxanthone, Michler's ketone, aminobenzophenones such as 4,4′-bisdiethylaminobenzophenone, 10-butyl-2-chloroacridone, 2-ethylanthrax Emissions, 9,10-phenanthrenequinone, there is camphorquinone and the like. These photopolymerization initiators may be used alone or in combination of two or more as required.

  When the active energy ray-curable lithographic printing ink of the present invention is cured by irradiating with ultraviolet rays, it can be cured only by adding a photopolymerization initiator, but in order to further improve the curability, a photosensitizer must be used in combination. You can also. Examples of such a photosensitizer include triethanolamine, methyldiethanolamine, dimethylethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, and benzoic acid. Examples include amines such as acid (2-dimethylamino) ethyl, 4-dimethylaminobenzoic acid (n-butoxy) ethyl, and 2-dimethylhexyl 4-dimethylaminobenzoate.

  The compounding quantity of a photoinitiator is 0.01-20 weight% in this printing ink, Preferably it is 0.05-10 weight%. If it is less than 0.01% by weight, the curing reaction is not sufficiently carried out, and if it exceeds 20 parts by weight, the thermal polymerization reaction is liable to occur and the stability as an ink is liable to be impaired.

  Furthermore, the active energy ray-curable lithographic printing ink of the present invention can be used by adding various additives such as a polymerization inhibitor, anti-friction agent, anti-blocking agent, slip agent and the like according to the purpose. .

  The atmosphere for irradiating the active energy rays is preferably an atmosphere substituted with an inert gas such as nitrogen gas. Before irradiating the active energy ray, the active energy ray curable composition layer is heated by an infrared heater or the like, or after irradiating the active energy ray, the active energy ray curable lithographic printing ink cured layer is heated by an infrared heater or the like. This is effective to finish curing quickly.

  The active energy ray of the present invention refers to ionizing radiation such as ultraviolet rays, electron beams, X-rays, α rays, β rays, γ rays, microwaves, high frequencies, etc., provided that radical active species can be generated. Any energy species may be used, such as visible light, infrared light, and laser light. Examples of ultraviolet ray generators include ultra-high pressure mercury lamps, high pressure mercury lamps, medium pressure mercury lamps, low pressure mercury lamps, metal halide lamps, xenon lamps, carbon arc lamps, helium / cadmium lasers, YAG lasers, excimer lasers, and argon lasers. and so on.

  The active energy ray-curable lithographic printing ink of the present invention is used at room temperature to 100 ° C., and the printing ink components are kneaded, mixed, and adjusted using a kneader, triple roll, attritor, sand mill, gate mixer, etc. Manufactured.

  The active energy ray-curable lithographic printing ink of the present invention is usually applied to lithographic offset printing using fountain solution, but is also suitably used for waterless printing without using fountain solution. The active energy ray-curable lithographic printing ink of the present invention includes foam prints, various book prints, various packaging prints such as carton paper, various plastic prints, seal / label prints, art prints, metal prints (art prints, Applied to printed matter such as beverage can printed matter, food printed matter such as canned food). Furthermore, it may be used as an overcoat varnish.

As an example of the composition of the active energy ray curable lithographic printing ink used in the present invention,
(A) Resin 10-40% by weight
(B) Active energy ray-curable compound 30 to 75% by weight
(C) Pigment (organic pigment / inorganic pigment) 5 to 40% by weight
Other (a) Non-reactive resin excluding resin 0-30% by weight
Photoinitiator, photosensitizer 0-15% by weight
Additive 1-10% by weight
Is mentioned.

  In addition, as the base material, non-coated paper such as fine paper, fine coated paper, art paper, coated paper, lightweight coated paper, coated paper such as cast coated paper, white paperboard, paperboard such as ball coat, synthetic paper Examples thereof include paper, aluminum vapor-deposited paper, and plastic sheets such as polypropylene, polyethylene, polyethylene terephthalate, and polyvinyl chloride.

EXAMPLES Next, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited by these Examples. In the present invention, “part” represents part by weight, and “%” represents% by weight.
An active energy ray-curable lithographic ink composition was prepared according to the following formulation.

Example 1
A stirrer, a reflux condenser with a water separator, and a thermometer four-necked flask were charged with 131 parts of Chinese rosin X (manufactured by Arakawa Chemical Industries) and 34 parts of maleic anhydride. Reacted for hours.
Thereafter, 115 parts of benzoic acid, 80 parts of phthalic anhydride, 140 parts of trimethylolpropane, 1.5 parts of p-toluenesulfonic acid monohydrate and 15 parts of xylene were added, followed by dehydration condensation at 240 ° C. for 15 hours. 21, GPC measurement A resin (R1) having a polystyrene-reduced weight average molecular weight (Mw) of 27,000 was obtained.
Next, 30 parts of resin (R1), 69.9 parts of dipentaerythritol hexaacrylate, and 0.1 part of hydroquinone were mixed in the same flask, and heated and melted at 120 ° C. to obtain varnish (V1).
Furthermore, 20 parts of Lionol Blue FG7330 (a cyan pigment manufactured by Toyo Ink Co., Ltd.), 60 parts of varnish (V1), 14.9 parts of trimethylolpropane tetraacrylate, 2.5 parts of 4,4′-bis (diethylamino) benzophenone , Irgacure 907 (manufactured by Ciba Specialty Chemicals Co., Ltd.) 2.5 parts, hydroquinone 0.1 part is kneaded in a three-roll mill at 40 ° C., and trimethylol is adjusted so that the ink tack is 9-10. The lithographic printing ink (C1) was obtained by adjusting with propanetetraacrylate.
The tack of the ink was measured with a roll temperature of 30 ° C., 400 rpm, and 1 minute after using an incometer manufactured by Toyo Seiki Co., Ltd.

[Example 2]
In the same manner as in Example 1, a resin (R2) having an acid value of 24 and Mw of 190000 was obtained with the composition shown in Table 1. Subsequently, lithographic printing ink (C2) was obtained with the composition shown in Table 2 and varnish (V2) with the composition shown in Table 3.

Example 3
In the same manner as in Example 1, a resin (R3) having an acid value of 19 and Mw of 21,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C3) was obtained with the composition shown in Table 2 and the varnish (V3) with the composition shown in Table 3.

[Comparative Example 1]
By the same operation as in Example 1, a resin (R5) having an acid value of 23 and Mw of 18,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C5) was obtained with the composition shown in Table 2 and the varnish (V5) with the composition shown in Table 3.

[Comparative Example 2]
In the same manner as in Example 1, a resin (R6) having an acid value of 22 and Mw of 18,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C6) was obtained with the formulation shown in Table 2 and the varnish (V6) with the formulation shown in Table 3.

[Evaluation of cured film properties]
The lithographic printing inks obtained in Examples 1 to 3 and Comparative Examples 1 to 2 were applied to maricoat paper (coated cardboard manufactured by Hokuetsu Paper Co., Ltd.) at 1 g / m @ 2 using an RI tester (manufactured by Meiko Seisakusho). Was applied at a coating amount of 120 W / cm and irradiated with ultraviolet rays at 60 m / min using one 120 W / cm air-cooled metal halide lamp (manufactured by Toshiba).
The curability, MEK resistance, friction resistance, and blocking resistance of the printed matter after ultraviolet irradiation were evaluated. The evaluation results are shown in Table 4.

  The curability was evaluated in four stages by visual observation of the state when the printed surface was rubbed with a cotton cloth. ◎: no change, ○: some scratches but no peeling, △: some (less than 50%) peeling, x: some (50% or more) or all Represents that peeling was observed.

  MEK resistance was evaluated in four stages by visual observation of the state when the printed surface was rubbed 30 times with a cotton swab dipped in MEK. ◎: No change, ○: Part of the surface was dissolved but no peeling was observed, Δ was partly (less than 50%), x was partly (50% or more) Or it represents that peeling was seen in all.

  The friction resistance of the coating film is based on JIS-K5701-1, using a Gakushin type friction fastness tester (manufactured by Tester Sangyo Co., Ltd.), using high-quality paper as a friction paper, The change of the friction surface was visually evaluated in four stages. ◎: no change, ○: some scratches but no peeling, △: some (less than 50%) peeling, x: some (50% or more) or all Represents that peeling was observed.

  According to JIS-K5701-1, the anti-blocking property is when the test piece with the printed surfaces facing each other is pressed to 1 kg / cm 2, left at a temperature of 60 ° C. and a humidity of 80% RH for 24 hours, and then pulled apart by hand. The resistance and the state of the printed surface were visually evaluated in four stages. ◎ has no resistance when separated and there is no change in the printed surface, ○ indicates there is resistance when separated but there is no change in the printed surface, or there is no resistance when separated, but it is part of the printed surface (less than 10%) Peeling was observed, Δ represents peeling on a part (less than 50%) of the printed surface, and x represents peeling on a part (50% or more) or all of the printed surface.

[Printability evaluation]
The lithographic printing inks obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were used with Lithrone 226 (Comorie Corporation's sheet-fed printing machine), and the Mitsubishi special art paper weight 90 kg / ream (Mitsubishi Paper Industries) ) Was subjected to a printing test of 20,000 sheets of each ink at 10,000 sheets / hour, and the solid state of the printed matter and the background stain were visually compared. The fountain solution is 1.5% ASTROMARK III clear (Toyo Ink Mfg. Co., Ltd.) and 3% isopropyl alcohol, and the water width is used to compare the printing conditions near the lower limit of the water width. Printing was carried out at a water dial value 2% higher than the lower limit value. The results are shown in Table 4.

As shown in Table 4, 80 to 100 mol% of an α, β-unsaturated carboxylic acid and a resin acid were added to the resin acid, followed by reaction with a polyhydric alcohol compound in an amount of 10 to 40% by weight. The lithographic printing inks of Examples 1 to 3 that are contained are excellent in curability by ultraviolet irradiation, and the cured film has good MEK resistance, friction resistance, and blocking resistance. dirt problem planographic printing inks KuMinoru施例1-3 was excellent in all the properties. On the other hand, Comparative Example 1 in which the resin acid was subjected to addition reaction with less than 50 mol% of the α, β-unsaturated carboxylic acid with respect to the resin acid, and Comparative Example containing less than 10% by weight of the resin acid in the resin The lithographic printing ink of No. 2 was poor in curability, MEK resistance, friction resistance, blocking resistance, and background stain, and none of the lithographic printing inks that were all good was obtained.

  By using the active energy ray-curable lithographic printing ink according to the present invention, it is possible to perform printing with excellent printability such as curability and stain resistance, and furthermore, a printed matter with excellent film strength such as abrasion resistance. Can be obtained. It can be used for a wide range of printing applications such as packaging packaging printing applications.

Claims (4)

In the active energy ray-curable lithographic printing ink containing (a) a resin, (b) an active energy ray-curable compound and (c) a pigment,
(A) A resin synthesized by reacting a resin acid with 80 to 100 mol% of an α, β-unsaturated carboxylic acid or anhydride based on the resin acid, and further reacting with a polyhydric alcohol The resin acid is 10 to 40% by weight in the total reaction compound (here, the total reaction compound is the total amount of the reaction compound in both the addition reaction and the reaction with the polyhydric alcohol). ),
(A) The resin is contained in an amount of 10 to 40% by weight of the total amount of the ink,
(B) the active energy ray-curable compound is contained in an amount of 30 to 75% by weight based on the total amount of the ink;
And (c) the pigment is 5 to 40% by weight of the total amount of the ink
An active energy ray-curable lithographic printing ink comprising: 2. The active energy ray-curable lithographic printing ink according to claim 1, wherein the resin acid has a conjugated double bond. The active energy ray-curable lithographic printing ink according to claim 1, wherein the α, β-unsaturated carboxylic acid or the anhydride is maleic acid or the anhydride, respectively. A printed matter obtained by printing the active energy ray-curable lithographic printing ink according to any one of claims 1 to 3 on a substrate and curing it with active energy rays.