JPWO2015093394A1 - Active energy ray-curable offset ink composition and printed matter using the same - Google Patents

Abstract

Provided are an active energy ray-curable printing ink composition that exhibits high curability and has both excellent emulsifying ability and offset printing ability, and a printed material thereof. An epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin with acrylic acid, wherein the ratio of α-glycol group to the total number of terminal structural sites derived from or derived from the glycidyloxy group of the bisphenol A type epoxy resin is 13C -The epoxy acrylate compound (A) which is a ratio of 5 mol% or less in the NMR measurement result is contained in the range of 10 to 60 mass% of the total amount, and the viscosity at 25 ° C is 40 to 200 millipascal seconds (mPa · s). Active energy ray-curable offset ink containing a polymerizable acrylate monomer (B) having a molecular weight of 250 to 550 and having two or more acrylic groups per molecule in a range of 5 to 40% by mass. Composition.

Description

  The present invention relates to an active energy ray-curable offset ink composition useful as a raw material for an active energy ray-curable offset ink or the like. Furthermore, the present invention relates to a printed material using the composition.

  The active energy ray-curable offset ink composition has been evaluated for its instantaneous curing property and is widely used mainly for package printing of paper containers and the like.

  In the active energy ray-curable offset ink composition, oligomers having a polymerizable group such as an acrylate group such as epoxy acrylate, urethane acrylate, and polyester acrylate are frequently used so as to have an instantaneous curing property (for example, patents). Reference 1).

  However, although these oligomers having a polymerizable group such as an acrylate group have the advantage of being excellent in curability, the fluidity and water resistance of the ink are particularly lowered due to the influence of the highly hydrophilic polymerizable group component. In addition, continuous printing at a stable concentration becomes difficult as compared with the oxidative polymerization type oil-based offset ink, and there are problems such as generation of damaged paper and a decrease in productivity.

  Taking the case of using the epoxy acrylate resin as an example, there was a disadvantage that the required emulsification ability was inferior. That is, in the offset printing in which the ink and water are continuously supplied to the printing plate at the same time and image formation is performed by utilizing the repulsive action of the ink and water, the ink is required to have high emulsification ability. Due to the strong hydrophilicity and inferior properties of properly releasing emulsified water, the ink is excessively emulsified during printing, and printing troubles such as a decrease in printing density often occur. On the other hand, as an active energy ray-curable UV ink having excellent emulsifying properties, a technique in which a rosin-modified phenol resin and an active energy ray-curable monomer are used in combination as a varnish is known (for example, see Patent Document 2). However, since the rosin-modified phenol resin does not have polymerizability with respect to active energy rays, there is a problem that the curability of the ink itself is lowered.

  As described above, there has been no active energy ray-curable offset printing ink that exhibits high curability and has high emulsification ability.

Japanese Patent Laid-Open No. Sho 61-218620 Japanese Patent No. 4734490

  Accordingly, the problem to be solved by the present invention is to develop high energy curability when used in printing ink, as well as an active energy ray curable composition having excellent emulsification ability and offset printing ability, excellent curability, An object of the present invention is to provide an active energy ray-curable printing ink having emulsifying properties and offset printing suitability, and a printed matter thereof.

  As a result of earnest research to solve the above problems, the present inventors have obtained an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid, and the glycidyloxy of the bisphenol A type epoxy resin. The ratio of α-glycol groups to the total number of terminal structure sites derived from or derived from groups is adjusted to a ratio of 5 mol% or less in 13C-NMR measurement results, and more than two acrylic groups per specific molecule By mixing an appropriate amount of the polymerizable acrylate monomer with which it is present, the present invention has been found by developing excellent curability and dramatically improving the emulsification characteristics of the printing ink itself and obtaining good printing characteristics. It came to.

  That is, the active energy ray-curable offset ink composition of the present invention is an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid, and is derived from the glycidyloxy group of the bisphenol A type epoxy resin. Alternatively, the epoxy acrylate compound (A) in which the ratio of α-glycol group to the total number of derived terminal structural sites is 5 mol% or less as a result of 13C-NMR measurement is contained in the range of 10 to 60 mass% of the total amount. And a polymerizable acrylate monomer (B) having a viscosity at 25 ° C. in the range of 40 to 200 millipascal seconds (mPa · s) and a molecular weight in the range of 250 to 550 and having two or more acrylic groups per molecule. Is contained in the range of 5 to 40% by mass. For the set ink compositions.

  The present invention further relates to an active energy ray-curable offset ink comprising the active energy ray-curable offset ink composition.

  The present invention further relates to a printed matter obtained by printing using the active energy ray-curable offset ink.

  According to the present invention, an active energy ray-curable offset ink that exhibits high curability when used in a printing ink composition and also has excellent curability, emulsification property, and offset printability, and a printed matter thereof are provided. it can.

  The active energy ray-curable offset ink composition of the present invention is an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid, and is derived from or derived from the glycidyloxy group of the bisphenol A type epoxy resin. The polymerizable acrylate monomer having a ratio of α-glycol group to the total number of terminal structure sites to be adjusted to a ratio of 5 mol% or less in 13C-NMR measurement results, and further having two or more acrylic groups per specific molecule The effects of the present invention can be achieved by mixing a suitable amount of.

  Here, in the epoxy acrylate compound, the terminal structure site derived from or derived from the glycidyloxy group is various terminal structure sites generated by the reaction of the epoxy group in the raw material epoxy resin and the carboxylic acid having a polymerizable unsaturated group. Or an epoxy group remaining unreacted, specifically, the following structural formulas (i) to (vi)

（構造式（ｉ）〜（iv）中、Ｒ^１及びＲ^２は、水素原子又はメチル基である。）
で表される各種の末端構造である。
言わばエポキシアクリレート不純物であるαグリコール構造部位は新水性が特に強く、印刷インキの乳化適性を低下させる傾向にあることから、αグリコール構造部位の含有率を制御することが好ましい。
本発明では、^１３Ｃ−ＮＭＲにて測定可能な末端構造の総数のうち、前記構造式（ｖ）で表されるαグリコール構造部位の含有率が５モル％以下となる割合に調整することにより、該重合性不飽和基含有樹脂を用いた印刷インキにおける硬化性が良好であると共に、優れた乳化特性が発現されるものである。本発明では、特に、３モル％以下であることが印刷インキとして用い、オフセット印刷を行った場合、印刷特性に優れたものとなる点から好ましい。

(In the structural formulas (i) to (iv), R ¹ and R ² are a hydrogen atom or a methyl group.)
Are various terminal structures.
In other words, the α glycol structure site, which is an epoxy acrylate impurity, is particularly strong in new water and tends to reduce the emulsification suitability of the printing ink. Therefore, it is preferable to control the content of the α glycol structure site.
In the present invention, by adjusting the proportion of the α glycol structure moiety represented by the structural formula (v) to 5 mol% or less of the total number of terminal structures measurable by ¹³ C-NMR. In addition, the curability of the printing ink using the polymerizable unsaturated group-containing resin is good, and excellent emulsification characteristics are exhibited. In the present invention, in particular, it is preferable that the content is 3 mol% or less as printing ink and when offset printing is performed, the printing characteristics are excellent.

  In the present invention, it is not necessary to include all of the various terminal structures (the structural formulas (i) to (vi)), and the α glycol structural site is based on the total number of terminal structures selected from these. It is sufficient that the content of is 5 mol% or less.

Here, the abundance ratio of the structural formulas (i) to (vi) can be measured by ¹³ C-NMR as described above. Specifically, each of the carbon atoms indicated by * below is indicated. It can be derived by the peak area ratio. When each peak overlaps with another carbon atom in another structure, the ratio may be obtained by excluding the area due to the other carbon atom.

（構造式（ｉ）〜（iv）中、Ｒ^１及びＲ^２は、水素原子又はメチル基である。）

(In the structural formulas (i) to (iv), R ¹ and R ² are a hydrogen atom or a methyl group.)

Here, the measurement method of ¹³ C-NMR can be performed under the following conditions.
[Model] "JNM-ECA500" manufactured by JEOL
[Measurement condition]
Sample concentration: 30% (w / v)
Measuring solvent: DMSO-d6
Integration count: 4000 times

  In the present invention, as described above, the existence ratio of each terminal structural site in the structural formulas (i) to (vi) is such that the α glycol structural site represented by the structural formula (v) is 5 mol% or less. In particular, it is preferably 3 mol% or less, but the other terminal structure site is, for example, that the α-addition structure site represented by the structural formula (i) is 70 mol% or more, more specifically, The α-addition structure moiety represented by the structural formula (i) is 70 mol% or more, and the α-addition structure moiety represented by the structural formula (i) is represented by the structural formula (ii). It is preferable from the viewpoint of curability and emulsification that the total amount with the β-addition structure site is 84% or more. In addition, the αβ addition structure site represented by the structural formula (iii) is preferably 5 mol% or less from the viewpoint of emulsification, and the monocarboxylic acid further having a polymerizable unsaturated group in the α addition structure. It is preferable from the point that sclerosis | hardenability becomes favorable that it is the ratio which the structural site | part represented by the said structural formula (iv) which is Michael addition structure is 8 mol% or less. Further, the epoxy group represented by the structural formula (vi) is an epoxy group remaining unreacted, and its abundance ratio is 2 mol% or less, particularly 1 mol% or less. Is preferred.

  Next, the epoxy resin is preferably a compound having two or more epoxy groups in one molecule, and bisphenol A type epoxy resin is an essential component, but one or more other epoxy resins are mixed. Can be used. For example, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type epoxy resin, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, hydrogenated bisphenol S type epoxy resin, hydrogenated bisphenol AD type epoxy Resin, bisphenol type epoxy resin such as tetrabromobisphenol A type epoxy resin; orthocresol novolak type epoxy resin; phenol novolak type epoxy resin, naphthol novolak type epoxy resin, bisphenol A novolak type epoxy resin, brominated phenol novolak type epoxy resin, Alkylphenol novolac epoxy resin, bisphenol S novolac epoxy resin, methoxy group-containing novolac epoxy resin, brominated pheno Novolak type epoxy resins such as luminolac type epoxy resins; other phenol aralkyl type epoxy resins (commonly known as epoxidized zylock resin), resorcin diglycidyl ether, hydroquinone diglycidyl ether, catechol diglycidyl ether, biphenyl type epoxy resin, Bifunctional epoxy resins such as tetramethylbiphenyl type epoxy resin; triglycidyl isocyanurate, triphenylmethane type epoxy resin, tetraphenylethane type epoxy resin, dicyclopentadiene-phenol addition reaction type epoxy resin, biphenyl modified novolac type epoxy Examples thereof include resins (epoxidized products of polyhydric phenol resins in which phenol nuclei are linked by bismethylene groups), methoxy group-containing phenol aralkyl resins, and the like.

  The bisphenol-type epoxy resin and the novolac-type epoxy resin are preferable from the viewpoint of printability, and in particular, the bisphenol-type epoxy resin having an epoxy equivalent of 170 to 500 g / eq, particularly the bisphenol A-type epoxy resin has excellent emulsification characteristics, This is preferable from the viewpoint of obtaining excellent printability when used as a printing ink.

  On the other hand, examples of the monocarboxylic acid having a polymerizable unsaturated group to be reacted with the epoxy resin include acrylic acid, methacrylic acid, and crotonic acid. Acrylic acid and methacrylic acid are particularly preferable from the viewpoint of printability. Since acrylic acid is preferable, in the present invention, an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid is used as an essential component.

  As described above, the epoxy acrylate compound (A) used in the active energy ray-curable offset ink composition of the present invention can be produced by reacting a bisphenol A type epoxy resin with acrylic acid. Is preferably carried out in the presence of a nitrogen-containing basic catalyst from the viewpoint of easily reducing the amount of α glycol to 5 mol% or less.

The nitrogen-containing basic catalyst used here is a basic compound having a nitrogen atom. Examples of the nitrogen-containing basic catalyst include primary amines such as n-butylamine, amylamine, hexylamine, cyclohexylamine, octylamine, and benzylamine,
Linear secondary amines such as diethylamine, dipropylamine, diisopropylamine and dibutylamine, secondary secondary amines such as aziridine, azetidine, pyrrolidine, piperidine, azepane and azocan and their alkyl substitution Amines, trimethylamine, triethylamine, tripropylamine, tributylamine, triethylenediamine, 1,4-diazabicyclo [2.2.2] octane, quinuclidine and aliphatic tertiary amines such as 3-quinuclidinol, dimethylaniline, etc. Aromatic tertiary amines and heterocyclic tertiary amines such as isoquinoline, pyridine, collidine and betapicoline, secondary amidines such as imidazole, purine, triazole and guanidine, pyrimidines, triazines and 1,8-dia Nitrogen atom-containing basic catalysts such as tertiary amidines such as bicyclo [5.4.0] undec-7-ene (DBU) and 1,5-diazabicyclo [4.3.0] non-5-ene (DBN) Is mentioned. These nitrogen atom-containing basic catalysts may be used alone or in combination of two or more.

  Among these nitrogen atom-containing basic catalysts, triethylamine or tetramethylammonium chloride is preferable because the amount of α-glycol in the polymerizable unsaturated group-containing resin can be easily reduced to 5% or less.

  Here, the amount of the nitrogen atom-containing basic catalyst used is 0.01 to 0.6% by mass, particularly 0.03 to 0.5% by mass, especially 0%, based on 100% by mass of the total weight of the epoxy acrylate compound. A range of 0.05 to 0.3% by mass is preferable from the viewpoint that the amount of α-glycol in the polymerizable unsaturated group-containing resin to be produced is reduced and the emulsification characteristics are good.

  Moreover, the method of manufacturing the said epoxy acrylate compound (A) is an epoxy resin and acrylic acid in presence of a nitrogen atom containing basic catalyst, and an epoxy group and a carboxyl group are 0.9 / 1.0-1. The ratio of 0 / 0.9 (molar ratio) and the nitrogen atom-containing basic catalyst is 0.01 to 0.6% by mass, preferably 0.03% relative to 100% by mass of the total weight of the raw material components. ˜0.5 mass%, particularly 0.05 to 0.3 mass%, and the reaction temperature is in the range of 80 to 125 ° C., preferably in the range of 90 to 110 ° C., and the epoxy equivalent is 8000 g / eq or more. Or the method of making it react until an acid value becomes 2.0 or less is preferable from the point which is easy to reduce the alpha glycol amount in an epoxy acrylate compound (A) to 5% or less.

  Furthermore, the reaction between the bisphenol A type epoxy resin and acrylic acid can be carried out in a reaction solvent using a radical polymerizable monomer that does not contain a site that reacts with a carboxyl group and an epoxy group as a reaction solvent. .

  Examples of the radical polymerizable monomers that do not contain a site that reacts with the carboxyl group and the epoxy group include N-vinylpyrrolidone, acryloylmorpholine, dicyclopentadienyl (meth) acrylate, dicyclopentenyloxyethyl (meta ) Acrylate, dicyclopentenyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, isobornyl (meth) acrylate, mono (meth) acrylate of bisphenol F, alkylene oxide Mono (meth) acrylate such as mono (meth) acrylate of addition bisphenol F; ethylene glycol di (meth) acrylate, dicyclopentenyl di (meth) acrylate, triethylene Recall di (meth) acrylate, tetraethylene glycol di (meth) acrylate, dimethylol tricyclodecane diacrylate, tripropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol Di (meth) acrylate, alkylene oxide-added 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, hydroxypivalate neo Di (meth) acrylate of pentyl glycol ester, di (meth) acrylate of bisphenol A, di (meth) acrylate of bisphenol F, alkylene oxide addition Di (meth) acrylates such as di (meth) acrylate of phenol A and di (meth) acrylate of alkylene oxide-added bisphenol F; trimethylolpropane tri (meth) acrylate, alkylene oxide-added trimethylolpropane tri (meth) acrylate, penta Examples include tri (meth) acrylates such as erythritol triacrylate; hexaacrylate of dipentaerythritol.

  As described above, the epoxy acrylate compound (A) thus obtained preferably has an epoxy equivalent of 8000 g / eq or more or an acid value of 2.0 or less. In addition, the epoxy acrylate compound (A) is adjusted in viscosity when the printing ink has a solution viscosity in a solution of 80% by mass nonvolatile matter when dissolved in butyl acetate in the range of 0.5 to 30 Pa · s. In addition, it is preferable from the viewpoint of excellent misting resistance and roll transferability when used as a printing ink, and those having a range of 1.0 to 10.0 Pa · s are particularly prominent in these effects. This is preferable.

  The epoxy acrylate compound (A) is preferably contained in the range of 10 to 60% by mass of the total amount of the ink composition, and has a viscosity at 25 ° C. in the range of 40 to 200 millipascal seconds (mPa · s). It is preferable to contain the polymerizable acrylate monomer (B) having two or more acrylic groups per molecule in the range of 5 to 40% by mass of the total amount of the ink composition. As for the polymerizable acrylate monomer (B), when a large amount of a monofunctional monomer having one acrylic group per molecule is used, it is difficult to obtain good curability, and when the molecular weight is less than 250, There is a possibility of causing expansion and deterioration of the rubber roller of the printing press. When the molecular weight exceeds 550, the monomer has a high viscosity. Therefore, the epoxy acrylate compound (A) in the ink composition is relatively used when used in a large amount. This is not preferable because it is difficult to obtain good curability and offset printing suitability. In particular, the epoxy acrylate compound (A) is contained in a range of 33 to 60% by mass with respect to the total amount of the ink composition in view of a good balance between the curability and the offset printing suitability, and the polymerizable property. The acrylate monomer (B) is contained in the range of 15.1 to 40% by mass of the total amount of the ink composition, and other components such as an initiator, a wax and a pigment are contained in a proportion of 51.9% by mass or less. preferable.

  The polymerizable acrylate monomer (B) is more preferably an active energy ray-curable monomer containing a bifunctional or trifunctional acrylic group, and the average number of moles of ethylene oxide added per mole of monomer molecules is 2 to 4. Ethylene oxide modified trimethylolpropane triacrylate in the range is particularly preferred. Since ethylene oxide-modified trimethylolpropane triacrylate has a low viscosity, it can relatively contain more epoxy acrylate compound (A) in the printing ink composition, and also provides an exquisite hydrophilic / hydrophobic balance. Thus, better offset printing suitability can be maintained. However, when the average added mole number of ethylene oxide per mole of monomer molecule of ethylene oxide-modified trimethylolpropane triacrylate exceeds 4, the hydrophilicity of the monomer becomes excessive and the offset printability tends to deteriorate.

  Next, examples of the photopolymerization initiator used when the active energy ray-curable offset ink composition of the present invention is an ultraviolet curable composition include an intramolecular cleavage type photopolymerization initiator and a hydrogen abstraction type photopolymerization initiator. It is done. Examples of the intramolecular cleavage type photopolymerization initiator include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy. 2-methylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenylketone, 2-hydroxy-1- {4- [4 -(2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2- Acetophenone compounds such as diethoxy-1,2-diphenylethane-1-one; 1- [4- (phenylthio)-, 2- O-benzoyloxime)], 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime), 3, 6 A carbazole compound such as bis (2-methyl-2-morpholinopropanonyl) -9-butylcarbazole, a benzoin compound such as benzoin, benzoin methyl ether, and benzoin isopropyl ether;

2-Benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one, 2- (dimethylamino) -2- (4-methylbenzyl) -1- (4-morpholinophenyl) butane Aminoalkylphenones such as -1-one, 2-methyl-2-morpholino ((4-methylthio) phenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone Compounds: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl -Acylphosphine oxide compounds such as pentylphosphine oxide; benzyl, methylphenyl Li oxy esters.

On the other hand, as the hydrogen abstraction type photopolymerization initiator, for example, benzophenone, methyl 4-phenylbenzophenone o-benzoylbenzoate, 4,4′-dichlorobenzophenone,
Hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide,
Benzophenone compounds such as acrylated benzophenone, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 3,3′-dimethyl-4-methoxybenzophenone; 2-isopropylthioxanthone, 2,4- Thioxanthone compounds such as dimethylthioxanthone, 2,4-diethylthioxanthone and 2,4-dichlorothioxanthone; aminobenzophenone compounds such as 4,4′-bisdimethylaminobenzophenone and 4,4′-bisdiethylaminobenzophenone; Examples include butyl-2-chloroacridone, 2-ethylanthraquinone, 9,10-phenanthrenequinone, camphorquinone, and the like. These photopolymerization initiators can be used alone or in combination of two or more. Among these, aminoalkylphenone compounds are preferable from the viewpoint of excellent curability, and particularly when a UV-LED light source that generates ultraviolet rays having an emission peak wavelength in the range of 350 to 420 nm is used as an active energy ray source. Is preferably used in combination with an aminoalkylphenone compound, an acylphosphine oxide compound, and an aminobenzophenone compound from the viewpoint of excellent curability.

  The amount of these polymerization initiators used is preferably in the range of 1 to 20% by mass as the total amount of use with respect to 100% by mass of the non-volatile components in the active energy ray-curable offset ink composition of the present invention. . That is, when the total amount of polymerization initiator used is 1% by mass or more, good curability can be obtained, and when it is 20% by mass or less, an unreacted polymerization initiator remains in the cured product. The problem of physical properties such as migration, solvent resistance, weather resistance and the like can be avoided. From the point that these performance balances become better, in particular, a range in which the total amount used is 3 to 15% by mass with respect to 100% by mass of the nonvolatile components in the active energy ray-curable ink composition of the present invention. It is more preferable that

  Moreover, when irradiating an ultraviolet-ray as an active energy ray and setting it as a cured coating film, sclerosis | hardenability can be improved further by utilizing a photosensitizer besides the above-mentioned polymerization initiator. Such photosensitizers include, for example, amine compounds such as aliphatic amines, ureas such as o-tolylthiourea, sulfur compounds such as sodium diethyldithiophosphate, s-benzylisothiouronium-p-toluenesulfonate, and the like. It is done. The use amount of these photosensitizers is 1 as the total use amount with respect to 100% by mass of the non-volatile component in the active energy ray-curable ink composition of the present invention from the viewpoint that the effect of improving curability is good. It is preferably in the range of ˜20% by mass, and in particular, the blending ratio of the epoxy acrylate compound (A) and the polymerizable acrylate monomer (B) can be increased to achieve a balance between curability and printability. Is preferably in the range of 1 to 10% by mass of the total amount of the ink composition.

  The active energy ray-curable composition of the present invention contains the polymerizable acrylate monomer (B) in a range of 5 to 40% by mass, preferably in a range of 15 to 40% by mass, based on the total amount of the ink composition. However, other known and used monomer compounds having an ethylenic double bond may be used in combination. Although a methacrylate monomer can be used in combination as appropriate, in the present invention, it is preferable to use an acrylate monomer having better curability. In addition, in the offset ink composition, it is preferable to use a bifunctional or higher functional acrylate monomer, which is more reactive than a monofunctional monomer, but depending on the application, adhesion to a printing substrate, flexibility of a cured coating film In order to obtain the necessary physical properties such as, it is possible to use a monofunctional acrylate monomer as appropriate.

  Examples of the monofunctional acrylate monomer include ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, lauryl acrylate, tridecyl acrylate, hexadecyl acrylate, octadecyl acrylate, isoamyl acrylate, isodecyl acrylate, isostearyl acrylate, and cyclohexyl. Acrylate, benzyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryl acrylate, glycidyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acetate Rate, 3-chloro-2-hydroxypropyl acrylate, diethylaminoethyl acrylate, nonylphenoxyethyl tetrahydrofurfuryl acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, isobornyl acrylate, dicyclopentanyl acrylate, dicyclopentenyloxy ethyl acrylate, etc. Is mentioned.

  Examples of the bifunctional or higher acrylate monomer include 1,4-butanediol diacrylate, 3-methyl-1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, 2 -Methyl-1,8-octanediol diacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate, tricyclodecane dimethanol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate Diacrylate of dihydric alcohol such as acrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol di Trivalent or more polyvalent polyacrylates such as acrylate, tris (2-hydroxyethyl) isocyanurate diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol polyacrylate Diacrylate of a diol obtained by adding 2 mol or more of ethylene oxide or propylene oxide to 1 mol of polyhydric alcohol, 1 mol of neopentyl glycol, obtained by adding 3 mol or more of ethylene oxide or propylene oxide to 1 mol of glycerin Triol triacrylate, 3 moles of ethylene oxide or propylene oxide per mole of trimethylolpropane Pressurized to triol di- or tri-acrylates obtained, polyacrylate polyoxyalkylene polyols and di acrylate of a diol obtained by adding 2 moles or more of ethylene oxide or propylene oxide to bisphenol A1 molar and the like.

  In the active energy curable offset ink composition of the present invention, a wax can be added for the purpose of improving curability. Examples of the wax include paraffin wax, carnauba wax, beeswax, microcrystalline wax, polyethylene wax, polyethylene oxide wax, polytetrafluoroethylene wax, amide wax and the like, and C8-C18 grades such as coconut oil fatty acid and soybean oil fatty acid. The fatty acid etc. which are in the range can be mentioned. On the other hand, although melt-type wax has poor compatibility with the epoxy acrylate compound (A) used in the present invention, ink fluidity tends to decrease, but polyethylene wax and polyethylene oxide wax are representative. A powder type or particle type polyolefin wax is preferred because it does not affect the compatibility and maintains good ink fluidity. Furthermore, it is more preferable if the polyolefin wax has a melting point in the range of 90 to 130 ° C and an average particle diameter D50 in the range of 1 to 10 micrometers. When the average particle diameter D50 is less than 1 micrometer, it is difficult to improve the curability, and when it exceeds 10 micrometers, the ink transfer property on the printing press is remarkably deteriorated and the offset printability is impaired. Moreover, it is preferable that the total amount of wax used is 0.1 to 5% by mass with respect to 100% by mass of the nonvolatile component in the active energy ray-curable composition of the present invention.

  In addition, as a measuring method of the said average particle diameter, it computed from the condition of the frequency distribution measured with Hitachi Ltd. operation type electron microscope S-3400N.

  In the active energy ray-curable offset ink composition of the present invention, pigments, dyes, extender pigments, organic or inorganic fillers, organic solvents, antistatic agents, antifoaming agents, viscosity adjustments as other blends of the above-described components Additives such as an agent, a light-resistant stabilizer, a weather-resistant stabilizer, a heat-resistant stabilizer, an ultraviolet absorber, an antioxidant, a leveling agent, and a pigment dispersant can be used.

  The active energy ray-curable offset ink composition of the present invention can be formed into a cured coating film by irradiating active energy rays after printing on a substrate. Examples of the active energy rays include ionizing radiation such as ultraviolet rays, electron beams, α rays, β rays, and γ rays. Among these, ultraviolet rays are particularly preferable from the viewpoint of curability and convenience.

  As described above, the active energy rays for curing the active energy ray-curable offset ink of the present invention are ionizing radiations such as ultraviolet rays, electron beams, α rays, β rays, and γ rays. Or, as a curing device, for example, germicidal lamp, ultraviolet fluorescent lamp, UV-LED (ultraviolet light emitting diode), carbon arc, xenon lamp, high pressure mercury lamp for copying, medium or high pressure mercury lamp, ultrahigh pressure mercury lamp, electrodeless lamp, Examples thereof include a metal halide lamp, ultraviolet rays using natural light as a light source, or an electron beam using a scanning type or curtain type electron beam accelerator.

  Examples of the pigment used in the active energy ray-curable offset ink of the present invention include publicly known organic pigments for coloring. For example, “Organic Pigment Handbook (Author: Isao Hashimoto, Publisher: Color Office, 2006) Organic pigments for printing inks published in the first edition), soluble azo pigments, insoluble azo pigments, condensed azo pigments, metal phthalocyanine pigments, metal-free phthalocyanine pigments, quinacridone pigments, perylene pigments, perinone pigments, isoindolinones Pigments, isoindoline pigments, dioxazine pigments, thioindigo pigments, anthraquinone pigments, quinophthalone pigments, metal complex pigments, diketopyrrolopyrrole pigments, carbon black pigments, other polycyclic pigments, and titanium oxide for white ink Can be mentioned. The blending ratio of these pigments is, for example, preferably 40 to 70% by mass in the ink composition in the case of white ink, but in the range of 10 to 25% by mass in the case of ordinary color ink. preferable.

  In the active energy ray-curable offset ink of the present invention, inorganic fine particles may be used as extender pigments. As inorganic fine particles, inorganic coloring pigments such as titanium oxide, kraftite, zinc white; lime carbonate powder, precipitated calcium carbonate, gypsum, clay (ChinaClay), silica powder, diatomaceous earth, talc, kaolin, alumina white, barium sulfate, Examples thereof include inorganic extender pigments such as aluminum stearate, magnesium carbonate, barite powder, and abrasive powder, silicone, and glass beads. The inorganic fine particles used as these extender pigments are used in the ink composition in the range of 0.1 to 20% by mass, thereby adjusting the fluidity of the ink, preventing misting, and preventing penetration into printing substrates such as paper. An effect can be obtained.

  The printing substrate suitable for the active energy ray-curable offset ink of the present invention includes a catalog, a poster, a flyer, a CD jacket, a direct mail, a brochure, a paper used for cosmetics, beverages, pharmaceuticals, toys, equipment packages, etc. Base materials: Films used for various food packaging materials such as polypropylene film and polyethylene terephthalate (PET) film, aluminum foil, synthetic paper, and other various base materials conventionally used as printing base materials.

  The present invention can be suitably used particularly in lithographic offset printing in which water is continuously supplied to the plate surface in that the emulsification characteristics of the ink are improved. Offset printers that supply water continuously are manufactured and sold by a large number of printer manufacturers. Examples include Heidelberg, Komori Corporation, Mitsubishi Heavy Industries Printing Paper Machinery, Man Roland, Ryobi, and KBA. In addition, the present invention can be suitably used in any sheet feeding system, such as a sheet-fed offset printing machine using a sheet form printing paper, an offset rotary printing machine using a reel form printing paper. More specifically, offset printing machines such as Heidelberg's Speedmaster series, Komori Corporation's Lithrone series, and Mitsubishi Heavy Industries Printing Paper Machine Co., Ltd.'s Diamond series can be mentioned.

  Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to these examples.

[Analytical method of glycol end group content of epoxy acrylate]
The amount of glycol end groups of the epoxy acrylate resins (EPA1) and (EPA2) produced in Synthesis Examples 1 and 2 was analyzed by ¹³ C-NMR.
Specifically, the terminal structure of each polymerizable unsaturated group-containing resin is an α addition structure, a β addition structure, an αβ addition structure, an α glycol represented by the following structural formula, and acrylic acid added to the α addition structure. Calculate the molar ratio of each functional group from the peak area ratio of the ¹³ C-NMR chart for the abundance ratio of carbon atoms indicated by the asterisk of the added Michael addition structure and the remaining epoxy group, and evaluated with these percentages. I did it.
In addition, the chemical shift of each carbon atom shown by AG in following Structural formula (1)-(7) is as follows when the peak of DMSO-d6 which is a measurement solvent is 39.5 ppm. Become.
Chemical shift of the carbon atom indicated by A: 71.1 ppm
Chemical shift of the carbon atom indicated by B: 65.6 ppm
Chemical shift of carbon atom indicated by C: 63.0 ppm
Chemical shift of carbon atom indicated by D: 62.5 ppm
Chemical shift of carbon atom represented by E: 59.7 ppm
Chemical shift of carbon atom represented by F: 60.0 ppm
Chemical shift of carbon atom indicated by G: 43.9 ppm
In addition, the peak of the carbon atom (shown by B) marked with * in the α addition structure of the following structural formula (1) is the * of the structural site present in the resin structure shown in the following structural formula (6). Since it overlaps with the carbon atom marked (marked with B), the existence ratio of the α-added structure is a value obtained by subtracting the peak area of the carbon atom represented by A in the following structural formula (6) from the peak area of B Was used.

（^１３Ｃ−ＮＭＲの測定条件）
［機種］日本電子製「ＪＮＭ−ＥＣＡ５００」
［測定条件］
試料濃度：３０％（ｗ／ｖ）
測定溶媒：ＤＭＳＯ−ｄ６
積算回数：４０００回

(Measurement conditions for ¹³ C-NMR)
[Model] "JNM-ECA500" manufactured by JEOL
[Measurement condition]
Sample concentration: 30% (w / v)
Measuring solvent: DMSO-d6
Integration count: 4000 times

[Synthesis example of epoxy acrylate]
Synthesis example 1
In a four-necked flask equipped with a stirrer, a thermometer and a cooling pipe, a liquid bisphenol A type epoxy resin (“Epiclon 850, epoxy equivalent 188 g / eq. Manufactured by DIC Corporation; hereinafter abbreviated as“ liquid BPA type epoxy resin ”). 435.1 parts by mass, acrylic acid 163.6 parts by mass, and methoquinone (polymerization inhibitor; hereinafter abbreviated as “MQ”) 0.1 part by mass were charged and heated to 100 ° C. 1.2 parts by mass of triethylamine (catalyst; hereinafter abbreviated as “TEA”) was added. The reaction was carried out at 100 ° C. for 15 hours, and the epoxy equivalent was 18,000 g / eq. An epoxy acrylate compound (EPA1) having an acid value of 0.4 mgKOH / g and a solution viscosity (80% by mass solution of butyl acetate in a nonvolatile content) of 1.8 Pa · s was obtained. Table 1 shows the abundance ratio of each terminal structure site based on ¹³ C-NMR measurement of the obtained polymerized epoxy acrylate compound (EPA1).

Synthesis example 2
In a four-necked flask equipped with a stirrer, a thermometer and a cooling pipe, a liquid bisphenol A type epoxy resin (“Epiclon 850, epoxy equivalent 188 g / eq. Manufactured by DIC Corporation; hereinafter abbreviated as“ liquid BPA type epoxy resin ”). 435.1 parts by mass, acrylic acid 163.6 parts by mass, and methoquinone (polymerization inhibitor; hereinafter abbreviated as “MQ”) 0.1 part by mass were charged and heated to 100 ° C. 1.2 parts by mass of triphenylphosphine (catalyst; hereinafter abbreviated as “TPP”) was added. By carrying out the reaction at 100 ° C. for 15 hours, the epoxy equivalent is 20,000 g / eq. An epoxy acrylate compound (EPA2) having an acid value of 0.5 mgKOH / g and a solution viscosity (80% by mass solution of butyl acetate in a nonvolatile content) of 1.8 Pa · s was obtained. Table 1 shows the proportion of each terminal structure site based on the measurement of ¹³ C-NMR of the obtained epoxy acrylate compound (EPA2).

[Production of active energy ray-curable offset ink]
According to the composition of Table 2 and Table 3, various ink compositions were obtained by kneading the inks of Examples 1 and 2 and Comparative Examples 1 to 8 with a three-roll mill. In addition, the numerical value of Table 2 and Table 3 is the mass%. The mixing ratio of the epoxy acrylate and the acrylate monomer was adjusted as shown in Tables 2 and 3 so that the tack value (TV) of the ink was 10. When a high viscosity acrylate monomer is used, it is necessary to relatively reduce the blending amount of epoxy acrylate in order to match the tack value. The tack value is a numerical value indicating the tackiness of the ink, that is, the larger the numerical value, the higher the tackiness and viscosity. In the measurement, 1.31 ml of evaluation ink was placed on a rubber roll of an incometer (manufactured by Toyo Seiki Co., Ltd.), and the tack value at the time when the ink was rotated at 32 ° C. and 400 rpm for 1 minute was recorded.
In addition, indigo pigments (Pigment Blue 15: 3, phthalocyanine blue) were used as coloring components in the inks of Examples 1 and 2 and Comparative Examples 1 to 8.

[Production method of exhibition color]
The active energy ray-curable ink composition thus obtained was used on a rubber roll and metal roll of the RI tester using a simple color developing machine (RI tester, manufactured by Toyoe Seiko Co., Ltd.) and using 0.10 ml of ink. Stretched uniformly over the surface of coated paper (“OK Top Coat Plus 57.5 kg, A size” manufactured by Oji Paper Co., Ltd.) over an area of 200 cm ² , measured with an indigo density of 1.6 (SpectroEye densitometer manufactured by X-Rite) The color was developed so that it could be applied uniformly, and a color-extracted product was produced. The RI tester is a test machine that develops ink on paper or film, and can adjust the amount of ink transferred and the printing pressure.

[Curing method using UV lamp light source]
Irradiation with ultraviolet rays (UV), which is an active energy ray, was performed on the color-extended product after the ink application to cure the ink film. Using a UV irradiation device equipped with a water-cooled metal halide lamp (output: 100 W / cm1 light) and a belt conveyor (made by Eye Graphics Co., Ltd., with a cold mirror), the color-exposed product is placed on the conveyor and directly under the lamp (irradiation distance: 11 cm) Was passed through at a speed of 100 meters per minute to cure the ink film. The ultraviolet irradiation amount in each condition was measured using an ultraviolet integrated light meter (UNIMETER UIT-150-A / receiver UVD-C365 manufactured by USHIO INC.).

[Evaluation method 1 of active energy ray-curable ink composition 1: fluidity]
Ink fluidity is measured by a spread meter method (parallel plate viscometer) according to JIS K5101, 5701. The ink sandwiched between two parallel plates placed horizontally is the weight of the load plate (115 Gram), the characteristics spreading concentrically were observed over time, and the spread diameter of the ink after 60 seconds was taken as a diameter value (DM [mm]) and evaluated in the following two stages. In the composition in which DM is less than 27 mm in this evaluation item, the ink fluidity is insufficient, so that defects in printability such as breakage on the printing press and transfer failure between ink rollers are likely to occur.
○: DM is 27 mm or more, and fluidity is good. X: DM is less than 27 mm, and fluidity is poor.

[Evaluation method 2 of active energy ray-curable ink composition 2: curability]
The curability was evaluated by the following two steps after checking the presence or absence of scratches on the surface of the developed product by the nail scratch method immediately after the ultraviolet irradiation. In the composition in which the ink cured film is scratched by rubbing with a nail, the printed material is easily damaged in each process such as cutting, box making and transportation of the printed material.
○: No scratches are generated in the nail scratches, and the curability is good. X: Scratches are generated in the nail scratches, and the curability is poor.

[Offset printing method of active energy ray-curable ink composition]
With respect to the produced active energy ray-curable inks of Examples 1 and 2 and Comparative Examples 1 to 8, the offset printability was evaluated. 9000 sheets per hour using a Man Roland offset printing machine (Roland R700 printing machine, 40-inch wide machine) equipped with a water-cooled metal halide lamp (output: 160 W / cm, 3 lamps used) as an ultraviolet irradiation device. Offset printing was performed at a printing speed of. For the printing paper, OK Top Coat Plus (57.5 kg, A size) manufactured by Oji Paper Co., Ltd. was used. The dampening water supplied to the printing plate was an aqueous solution in which 98% by mass of tap water and 2% by mass of an etchant (FST-700, manufactured by DIC) were mixed.

[Evaluation method 3 of active energy ray-curable ink composition: suitability for offset printing]
As an evaluation method of offset ink printing suitability, first, set the water supply dial of the printing press to 40 (standard water amount), and the printed material density is standard process indigo density 1.6 (measured with X-Rite SpectroEye densitometer). The ink supply key was operated so that the ink supply key was fixed when the density was stabilized. Thereafter, 300 sheets were printed under the condition that the water supply dial was changed from 40 to 55 and the water supply amount was increased with the ink supply key fixed, and the indigo density of the printed material after 300 sheets was measured. Even when the amount of water supply is increased, the smaller the decrease in the density of the printed matter, the better the emulsification suitability and the better the printability. The printability of the active energy ray-curable ink was evaluated according to the following criteria.
3: The indigo density of the printed material is 1.5 or more, and the offset printability is good 2: The indigo density of the printed material is 1.4 or more and less than 1.5, and the offset printability is medium 1: The indigo density of the printed material is less than 1.4, and the offset printability is poor.

(Measurement of weight average molecular weight)
In addition, the measurement of the weight average molecular weight (polystyrene conversion) by GPC in this invention was performed on condition of the following using the Tosoh Corp. HLC8220 system.
Separation column: 4 TSKgelGMH _HR- N manufactured by Tosoh Corporation are used. Column temperature: 40 ° C. Moving layer: Tetrahydrofuran manufactured by Wako Pure Chemical Industries, Ltd. Flow rate: 1.0 ml / min. Sample concentration: 1.0 mass%. Sample injection volume: 100 microliters. Detector: differential refractometer.

ミラマーＭ３１３０：エチレンオキサイド（平均３モル）変性トリメチロールプロパントリアクリレート（ＥＯ３−ＴＭＰＴＡ）、ＭＩＷＯＮ社製、２５℃におけるモノマー粘度６０ミリパスカル秒、重量平均分子量４２８
ミラマーＭ３００：トリメチロールプロパントリアクリレート（ＴＭＰＴＡ）、ＭＩＷＯＮ社製、２５℃におけるモノマー粘度１００ミリパスカル秒、重量平均分子量２９６
ミラマーＭ４１０：ジトリメチロールプロパンテトラアクリレート（ＤＴＭＰＴＡ）、ＭＩＷＯＮ社製、２５℃におけるモノマー粘度６００ミリパスカル秒、重量平均分子量４６６
ミラマーＭ６００：ジペンタエリスリトールヘキサアクリレート（ＤＰＨＡ）、ＭＩＷＯＮ社製、２５℃におけるモノマー粘度５２５０ミリパスカル秒、重量平均分子量５７８
ミラマーＭ３１６０：エチレンオキサイド（平均６モル）変性トリメチロールプロパントリアクリレート（ＥＯ６−ＴＭＰＴＡ）、ＭＩＷＯＮ社製、２５℃におけるモノマー粘度８０ミリパスカル秒、重量平均分子量５６０
ＰＥＴＡ−Ｋ：ペンタエリスリトールテトラアクリレート（ＰＥＴＡ）、ダイセル・オルネクス社製、２５℃におけるモノマー粘度８００ミリパスカル秒、重量平均分子量３５２
ミラマーＭ２４０：エチレンオキサイド（平均４モル）変性ビスフェノールＡジアクリレート（ＢｉｓＡ−ＥＯ４−ＤＡ）、ＭＩＷＯＮ社製、２５℃におけるモノマー粘度１１００ミリパスカル秒、重量平均分子量５１２
Ｓ−３８１−Ｎ１：粉体ポリオレフィンワックス、シャムロック社製、平均粒子径Ｄ５０＝５ミクロン、融点９７℃
ＨＥＬＩＯＧＥＮ ＢＬＵＥ Ｄ７０７９：Ｐｉｇｍｅｎｔ Ｂｌｕｅ１５：３（フタロシアニンブルー、藍顔料）、ＢＡＳＦ社製
ハイフィラー ＃５０００ＰＪ：タルク（含水ケイ酸マグネシウム）、松村産業社製
炭酸マグネシウムＴＴ：塩基性炭酸マグネシウム、ナイカイ塩業社製
Ｉｒｇａｃｕｒｅ９０７：２−メチル−１−［４−（メチルチオ）フェニル］−２−モノフォリノプロパン−１−オン、ＢＡＳＦ社製
ＥＡＢ―ＳＳ：４，４’−ビス（ジエチルアミノ）ベンゾフェノン、大同化成工業社製
Ｑ−１３０１：Ｎ−ニトロソフェニルヒドロキシルアミンアルミニウム塩、和光純薬工業社製

Miramar M3130: Ethylene oxide (average 3 mol) modified trimethylolpropane triacrylate (EO3-TMPTA), manufactured by MIWON, monomer viscosity at 25 ° C. 60 millipascal seconds, weight average molecular weight 428
Miramar M300: Trimethylolpropane triacrylate (TMPTA), manufactured by MIWON, monomer viscosity at 25 ° C. 100 millipascal seconds, weight average molecular weight 296
Miramar M410: ditrimethylolpropane tetraacrylate (DTMPTA), manufactured by MIWON, monomer viscosity at 25 ° C. 600 millipascal seconds, weight average molecular weight 466
Miramar M600: Dipentaerythritol hexaacrylate (DPHA), manufactured by MIWON, monomer viscosity at 25 ° C., 5250 millipascal seconds, weight average molecular weight 578
Miramar M3160: ethylene oxide (average 6 mol) modified trimethylolpropane triacrylate (EO6-TMPTA), manufactured by MIWON, monomer viscosity at 25 ° C., 80 millipascal seconds, weight average molecular weight 560
PETA-K: Pentaerythritol tetraacrylate (PETA), manufactured by Daicel Ornex Co., Ltd., monomer viscosity at 25 ° C., 800 millipascal seconds, weight average molecular weight 352
Miramar M240: ethylene oxide (average 4 mol) modified bisphenol A diacrylate (BisA-EO4-DA), manufactured by MIWON, monomer viscosity at 25 ° C. 1100 millipascal seconds, weight average molecular weight 512
S-381-N1: Powdered polyolefin wax, manufactured by Shamrock, average particle diameter D50 = 5 microns, melting point 97 ° C.
HELIOGEN BLUE D7079: Pigment Blue 15: 3 (phthalocyanine blue, indigo pigment), high filler manufactured by BASF # 5000PJ: talc (hydrous magnesium silicate), magnesium carbonate TT manufactured by Matsumura Sangyo Co., Ltd. Irgacure 907: 2-methyl-1- [4- (methylthio) phenyl] -2-monoforinopropan-1-one, EAB-SS manufactured by BASF: 4,4′-bis (diethylamino) benzophenone, Daido Kasei Kogyo Co., Ltd. Q-1301: N-nitrosophenylhydroxylamine aluminum salt, manufactured by Wako Pure Chemical Industries, Ltd.

As a result of earnest research to solve the above problems, the present inventors have obtained an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid, and the glycidyloxy of the bisphenol A type epoxy resin. The α addition structure site is adjusted to a ratio of 70 mol% or more and the α-glycol group ratio to 5 mol% or less in the 13C-NMR measurement result with respect to the total number of terminal structure sites derived from or derived from the group, and further specified By mixing an appropriate amount of a polymerizable acrylate monomer having two or more acrylic groups per molecule, it exhibits excellent curability and drastically improves the emulsifying properties of the printing ink itself, resulting in good printing properties. As a result, the present invention has been completed.

That is, the active energy ray-curable offset ink composition of the present invention is an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid, and is derived from the glycidyloxy group of the bisphenol A type epoxy resin. Or the total amount of the epoxy acrylate compound (A) in which the α-addition structure site is 70 mol% or more and the α-glycol group ratio is 5 mol% or less in the 13C-NMR measurement result with respect to the total number of terminal structure sites derived In the range of 10 to 60% by mass, and the viscosity at 25 ° C. is in the range of 40 to 200 millipascal seconds (mPa · s) and the molecular weight is in the range of 250 to 550, and two or more acrylics per molecule The polymerizable acrylate monomer (B) having a group is contained in the range of 5 to 40% by mass. To the active energy ray-curable offset ink composition to.

The active energy ray-curable offset ink composition of the present invention is an epoxy acrylate compound obtained by reacting a bisphenol A type epoxy resin and acrylic acid, and is derived from or derived from the glycidyloxy group of the bisphenol A type epoxy resin. The ratio of α-addition structure sites to the total number of terminal structure sites to be adjusted is 70 mol% or more, and the proportion of α-glycol groups is 5 mol% or less as determined by 13C-NMR measurement. By mixing an appropriate amount of the above polymerizable acrylate monomer having an acrylic group, the effects of the present invention are achieved.

In the present invention, it is not necessary to include all of the various terminal structures (the structural formulas (i) to (vi)), and the α-added structure site is based on the total number of terminal structures selected from these. May be 70 mol% or more and the content of the α glycol structure site may be 5 mol% or less.

As described above, the epoxy acrylate compound (A) used in the active energy ray-curable offset ink composition of the present invention can be produced by reacting a bisphenol A type epoxy resin with acrylic acid. It is preferable to react in the presence of a nitrogen-containing basic catalyst from the viewpoint that the α-addition structure site can be easily adjusted to 70 mol% or more and the amount of αglycol can be adjusted to 5 mol% or less.

Among these nitrogen atom-containing basic catalysts, triethylamine or tetramethylammonium chloride adjusts the α-addition structure site in the polymerizable unsaturated group-containing resin to 70 mol% or more and the α glycol amount to 5% or less. It is preferable because it is easy.

Moreover, the method of manufacturing the said epoxy acrylate compound (A) is an epoxy resin and acrylic acid in presence of a nitrogen atom containing basic catalyst, and an epoxy group and a carboxyl group are 0.9 / 1.0-1. The ratio of 0 / 0.9 (molar ratio) and the nitrogen atom-containing basic catalyst is 0.01 to 0.6% by mass, preferably 0.03% relative to 100% by mass of the total weight of the raw material components. ˜0.5 mass%, particularly 0.05 to 0.3 mass%, and the reaction temperature is in the range of 80 to 125 ° C., preferably in the range of 90 to 110 ° C., and the epoxy equivalent is 8000 g / eq or more. Alternatively, the method of reacting until the acid value is 2.0 or less is preferable because the α-addition structure site in the epoxy acrylate compound (A) is 70 mol% or more and the α glycol amount is easily adjusted to 5% or less. .

Claims (4)

Ratio of α-glycol group to the total number of terminal structure sites derived from or derived from glycidyloxy group of bisphenol A type epoxy resin, which is an epoxy acrylate compound obtained by reacting bisphenol A type epoxy resin and acrylic acid Contains an epoxy acrylate compound (A) in a proportion of 5 mol% or less in ¹³ C-NMR measurement results in a range of 10 to 60 mass% of the total amount of the ink composition, and further has a viscosity at 25 ° C. of 40 to 200 mm. A polymerizable acrylate monomer (B) having two or more acrylic groups per molecule in a range of Pascal second (mPa · s) and a molecular weight in a range of 250 to 550 is contained in a range of 5 to 40% by mass. An active energy ray-curable offset ink composition. The active energy ray according to claim 1, wherein the polymerizable acrylate monomer (B) is ethylene oxide-modified trimethylolpropane triacrylate, and the average number of moles of ethylene oxide added per mole of monomer molecules is in the range of 2 to 4. A curable offset ink composition. The active energy ray-curable type according to claim 1, further comprising a polyolefin wax (C) having a melting point in the range of 90 to 130 ° C and an average particle diameter D50 in the range of 1 to 10 micrometers. Offset ink composition. The printed matter formed by printing the active energy ray hardening-type offset ink composition as described in any one of Claims 1-3.