JP2000160086A - Radiation curable printing ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink composition which has minimum odor and color degradation, is curable with light of practical intensity and radiation and gives a cured coating film with a high strength by blending, as essential components, a specific compound, a compound having an acryloyl or methacryloyl group having a specific averaged number of functioning groups and a light polymerization initiator. SOLUTION: This composition contains, as essential components, 10-60 wt.% of a compound of formula I, 15-65% of an acryloyl or methacryloyl group having 4-6 functioning groups on average and 2-5 wt.% of a light polymerization initiator. In formula I, (m) and (n) are each 1-5, m+n is not more than 6; X1, Y1, X2 and Y2 are each H or an alkyl group; R11 and R12 are each a hydrocarbon bonding consisting of an alkylene group or the like; G1 and G2 are each an ester bonding, a urethane bonding or the like; R2 consists of a normal/ branched alkylene group or the like one of whose organic groups is a (poly)ether coupling chain, a (poly)ester coupling chain or a (poly)urethane coupling chain of an average molecular weight of 100-100,000, consisting of ether bondings or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation-curable printing ink composition using a maleimide derivative which is cured by irradiation with radiation.

[0002]

2. Description of the Related Art Radiation-curable printing inks using a radiation-curable composition have advantages such as low volatility and low energy cost because they use almost no diluting solvent, and have been growing rapidly in recent years. However, since the photocurable composition alone does not initiate polymerization, it is necessary to use a photopolymerization initiator in combination. Generally, in a cured product of a printing ink containing a large amount of a photoinitiator having an aromatic ring, an unreacted photopolymerization initiator or a photoinitiator decomposition product often remains,
When light or heat acts on the cured product, there is a problem that the cured product yellows or generates an odor. In particular, when a high-temperature body such as a heat-sensitive head comes into contact, the generation of a bad smell from the cured product becomes remarkable.

Further, a cured product of a printing ink containing a large amount of a photopolymerization initiator is unsuitable for use as a food packaging material because unreacted photopolymerization initiator bleeds when left in water or the like. There is difficulty. In order to improve the disadvantages of the photocurable resin composition containing these photopolymerization initiators, as a photocurable composition containing no photopolymerization initiator, a curable resin composition containing a maleimide derivative has been proposed. Although problems such as bad smell and burning are solved, there is a problem that the curing speed is slow and the strength of the cured coating film is low. Further, although an attempt was made to improve the strength of a cured coating film by using a composition comprising the above-mentioned photocurable composition and a compound containing an acryloyl group or a methacryloyl group, it has not reached a practical level.

[0004]

The problem to be solved by the present invention is to minimize problems such as bad smell and color burn, to cure with practical light intensity and light irradiation amount, and to obtain the strength of the cured coating film. Is to provide a radiation-curable printing ink composition having a high value.

[0005]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a photocurable compound containing a specific maleimide derivative, a compound containing an acryloyl group or a methacryloyl group, and a photopolymerizable compound. The present inventors have found that the above problems can be solved by a radiation-curable printing ink composition containing an initiator, and have completed the present invention.

That is, the first constitution of the present invention is that the compound represented by the general formula (1) is 10 to 60% by weight, the compound having an average number of functional groups of 4 to 6 having an acryloyl group or a methacryloyl group is 15 to 65% by weight. And a radiation-curable printing ink composition containing 2 to 5% by weight of a photopolymerization initiator as an essential component.

[0007]

Embedded image

(Wherein, m and n each independently represent 1 to 5)
Where m + n is 6 or less. X1, Y
1, X2 and Y2 each independently represent hydrogen or an alkyl group. R11 and R12 each independently represent a hydrocarbon bond selected from the group consisting of an alkylene group, a cycloalkylene group, an arylalkylene group and a cycloalkylalkylene group. G1 and G2 each independently represent an ester bond or a urethane bond.
R2 represents a linear alkylene group, a branched alkylene group,
An alkylene group having a hydroxyl group, a cycloalkylene group,
An average in which at least one organic group selected from the group consisting of an aryl group and an arylalkylene group is connected by at least one bond selected from the group consisting of (a) an ether bond, (b) an ester bond, and (c) a urethane bond. (A) (poly) ether linked chain, (B) (poly) ester linked chain or (C) having a molecular weight of 100 to 100,000
Represents a (poly) urethane linking chain. )

Further, in the second configuration of the present invention, G1 and G2 in the above-mentioned general formula (1) are each independently -C
An ester bond represented by OO- or -OCO-,
R2 represents a linear alkylene group, a branched alkylene group,
An alkylene group having a hydroxyl group, a cycloalkylene group,
At least one organic group selected from the group consisting of an aryl group and an arylalkylene group is connected by at least one bond selected from the group consisting of (a) an ether bond and (b) an ester bond;
000 (A) (poly) ether linked chains or (B)
A radiation-curable printing ink composition having a (poly) ester connecting chain.

A third structure of the present invention is a compound having an acryloyloxy group or a methacryloyloxy group having an average number of functional groups of 4 to 6 containing 30 to 60% by weight of the compound represented by the general formula (1). A radiation-curable printing ink composition comprising 35 to 65% by weight and 2 to 5% by weight of a photopolymerization initiator as essential components.

In a fourth aspect of the present invention, the compound represented by the general formula (1) is 10 to 30% by weight, the compound having an average number of functional groups of 4 to 6 and having an acryloyloxy group or a methacryloyloxy group. A radiation-curable printing ink composition comprising 50% by weight, 2 to 5% by weight of a photopolymerization initiator and a pigment as essential components.

In a fifth aspect of the present invention, the compound having an acryloyloxy group or a methacryloyloxy group is (A-1) (poly) ester (meth) acrylate or (A-2) urethane (meth) acrylate. , (A-
3) Epoxy (meth) acrylate, (A-4) (poly) ether (meth) acrylate, (A-5) alkyl (meth) acrylate or alkylene (meth) acrylate, (A-6) having an aromatic ring (meth) Radiation-curable printing according to any one of the first to fourth aspects of the invention, which is at least one compound selected from the group consisting of)) acrylates and (A-7) (meth) acrylates having an alicyclic structure. It is an ink composition.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the maleimide derivative represented by the above general formula (1) used in the present invention, in the above general formula (1), m and n each independently represent an integer of 1 to 5, m + n is an integer of 2 or more and 6 or less. X1, Y1, X2 and Y2 each independently represent hydrogen or an alkyl group, but is preferably hydrogen, and when it is an alkyl group, an alkyl group having 1 to 12 carbon atoms is preferable.

R11 and R12 each independently represent a hydrocarbon bond selected from the group consisting of an alkylene group, a cycloalkylene group, an arylalkylene group and a cycloalkylalkylene group. Here, the alkyl group may have a branched chain, and the arylalkylene group or the cycloalkyl-alkylene group may have an aryl group or a cycloalkyl group in the main chain or the branched chain, respectively. Examples of such a group include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, an undecamethylene group, and a dodecamethylene group. Linear alkylene group such as methylene group; propylene group, 1-methyl-trimethylene group, 2-
Alkyl such as methyl-trimethylene group, 1-methyl-tetramethylene group, 2-methyl-tetramethylene group, 1-methyl-pentamethylene group, 2-methyl-pentamethylene group, 3-methyl-pentamethylene group, neopentyl group, etc. An alkylene group having a branched chain; in a main chain or a side chain such as a cyclopentylene group, a cyclohexylene group, a cyclohexylmethylene group, a 1-cyclohexyl-ethylene group, a 1-cyclohexyl-tetraethylene group, or a 2-cyclohexyl-tetraethylene group; A cycloalkylene group or a cycloalkyl-alkylene group having a cycloalkyl group; a benzylene group, a 2,2-diphenyl-trimethylene group,
-Phenyl-ethylene group, 1-phenyl-tetraethylene group, 2-phenyl-tetraethylene group and the like, an aryl group having an aryl group in a main chain or a side chain, an arylalkylene group, and the like, but are not limited thereto. Not something.

G1 and G2 each independently represent an ester bond or a urethane bond.

R2 is at least one organic group selected from the group consisting of a linear alkylene group, a branched alkylene group, an alkylene group having a hydroxyl group, a cycloalkylene group, an aryl group, an arylalkylene group and an isocyanuric group; An average molecular weight of 100 to 10 linked by at least one bond selected from the group consisting of an ether bond, (b) an ester bond and (c) a urethane bond.
000 (A) (poly) ether tethers, (B)
(Poly) ester connecting chain or (C) (poly) urethane connecting chain. R2 may be a connecting chain composed of an oligomer or polymer in which these connecting chains are repeated as one unit.

A specific example of the connecting chain representing R2 is as follows.

(A) at least one hydrocarbon group selected from the group consisting of a linear alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group and an aryl group; (Poly) ether (poly) having an average molecular weight of 100 to 100,000 and having one or a repeating unit thereof linked by an ether bond
Linking chain composed of all:

(B) at least one hydrocarbon group selected from the group consisting of a linear alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group and an aryl group; (Poly) ester (poly) having an average molecular weight of 100 to 100,000 and having one or a repeating unit thereof bonded by an ester bond
Linking chain composed of all:

(C) at least one hydrocarbon group selected from the group consisting of a linear alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group and an aryl group; (Poly) ether (poly) having an average molecular weight of 100 to 100,000 and having one or a repeating unit thereof linked by an ether bond
Linking chain composed of (poly) carboxylic acid obtained by esterifying all and dicarboxylic acid:

(D) at least one hydrocarbon group selected from the group consisting of a straight-chain alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group and an aryl group; From (poly) carboxylic acid obtained by esterifying dicarboxylic acid with (poly) ester (poly) ol having an average molecular weight of 100 to 100,000 and having one or a repeating unit thereof bonded by an ether bond and / or an ester bond. Composed linking chains:

(E) at least one hydrocarbon group selected from the group consisting of a linear alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group, and an aryl group; (Poly) ether (poly) having an average molecular weight of 100 to 100,000 and having one or a repeating unit thereof linked by an ether bond
Linking chain composed of (poly) isocyanate obtained by urethane-forming all and organic (poly) isocyanate:

(F) at least one hydrocarbon group selected from the group consisting of a linear alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group and an aryl group; Urethaneated (poly) of (poly) ester (poly) ol having an average molecular weight of 100 to 100,000 having one or a repeating unit thereof bonded by an ether bond and / or an ester bond and an organic (poly) isocyanate Linking chain composed of isocyanate:

(G) at least one hydrocarbon group selected from the group consisting of a linear alkylene group having 1 to 24 carbon atoms, a branched alkylene group having 1 to 24 carbon atoms, a cycloalkylene group and an aryl group; A linking chain such as a linking chain obtained by ring-opening a (poly) epoxide having an average molecular weight of 100 to 100,000 having one or a repeating unit thereof bonded by an ether bond, but is not limited to these examples. It is not something to be done.

Examples of the (poly) ether (poly) ol constituting the linking chain (a) include polyalkylene glycols such as polyethylene glycol, polypropylene glycol, polybutylene glycol and polytetramethylene glycol; ethylene glycol; Propanediol, propylene glycol, tetramethylene glycol, pentamethylene glycol, hexanediol, neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol, diglycerin,
Ditrimethylolpropane, ethylene oxide-modified alkylene glycols such as dipentaerythritol,
Propylene oxide modified, butylene oxide modified,
Examples include modified tetrahydrofuran, and among these, various modified alkylene glycols are preferable.
Further, hydrocarbons such as copolymers of ethylene oxide and propylene oxide, copolymers of propylene glycol and tetrahydrofuran, copolymers of ethylene glycol and tetrahydrofuran, polyisoprene glycol, hydrogenated polyisoprene glycol, polybutadiene glycol, and hydrogenated polybutadiene glycol Polyols, polyvalent hydroxyl compounds such as polytetramethylene hexaglyceryl ether (tetrahydrofuran-modified hexaglycerin) and the like are recommended, but not limited thereto.

Examples of the (poly) ester (poly) ol constituting the linking chain (b) include polyalkylene glycols such as polyethylene glycol, polypropylene glycol, polybutylene glycol and polytetramethylene glycol; ethylene glycol; Propanediol, propylene glycol, tetramethylene glycol, pentamethylene glycol, hexanediol, neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol, diglycerin,
Ditrimethylolpropane, ε-caprolactone-modified, γ-butyrolactone-modified, δ-valerolactone-modified, methylvalerolactone-modified alkylene glycols such as dipentaerythritol, and aliphatic dicarboxylic acids such as adipic acid and dimer acid. Polyester polyols such as aliphatic polyester polyols which are reactants with polyols such as neopentyl glycol and methylpentanediol, and aromatic polyester polyols which are reactants of aromatic dicarboxylic acids such as terephthalic acid with polyols such as neopentyl glycol Fumaric acid, phthalic acid, isophthalic acid of polyhydric hydroxyl group compounds such as polycarbonate polyol, acrylic polyol, polytetramethylene hexaglyceryl ether (tetrahydrofuran-modified hexaglycerin) Polyhydric hydroxyl group-containing compounds obtained by esterification with dicarboxylic acids such as itaconic acid, adipic acid, sebacic acid, and maleic acid, and obtained by transesterification of polyhydric hydroxyl group-containing compounds such as glycerin with fatty acid esters of animals and plants. And the like, but are not limited to polyhydric hydroxyl group-containing compounds such as monoglyceride.

Examples of the (poly) carboxylic acid constituting the linking chain (c) include succinic acid, adipic acid, phthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, pyromellitic acid, fumaric acid, and isophthalic acid. (Poly) ether (poly) carboxylic acid, etc. obtained by esterification of dicarboxylic acids such as itaconic acid, adipic acid, sebacic acid, and maleic acid with (poly) ether (poly) ol shown in (a) However, the present invention is not limited to this.

As the (poly) carboxylic acid constituting the linking chain (d), for example, succinic acid, adipic acid, phthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, pyromellitic acid, fumaric acid, isophthalic acid (Poly) ester (poly) carboxylic acid obtained by esterification of dicarboxylic acid of itaconic acid, adipic acid, sebacic acid, and maleic acid with (poly) ester (poly) ol shown in (b). However, the present invention is not limited to this.

Examples of the (poly) isocyanate constituting the linking chain (e) include methylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, Dimer of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate,
p-xylene diisocyanate, m-xylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-
Aromatic diisocyanate compounds such as dimethylbiphenyl-4,4'-diisocyanate, aliphatic diisocyanate compounds such as trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate, isophorone diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methylcyclohexane -2,4 (or 2,6) diisocyanate,
(A) alicyclic diisocyanate such as 1,3- (isocyanatomethylene) cyclohexane, triisocyanate such as tris (isocyanatemethylene) isocyanurate and tris (isocyanate hexamethylene) isocyanurate; Obtained by urethanization with polyether polyol (poly)
Examples include, but are not limited to, ether (poly) isocyanate.

Examples of the (poly) isocyanate constituting the linking chain (f) include methylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, Dimer of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate,
p-xylene diisocyanate, m-xylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-
Aromatic diisocyanate compounds such as dimethylbiphenyl-4,4'-diisocyanate, aliphatic diisocyanate compounds such as trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate, isophorone diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methylcyclohexane -2,4 (or 2,6) diisocyanate,
(B) an organic polyisocyanate such as an alicyclic diisocyanate such as 1,3- (isocyanatomethyl) cyclohexane, a triisocyanate such as tris (isocyanatomethylene) isocyanurate and tris (isocyanate hexamethylene) isocyanurate; Polyester polyisocyanate obtained by urethanation with (poly) ester (poly) ol, and the like, but are not limited thereto.

Examples of the (poly) epoxide constituting the linking chain (g) include (methyl) epichlorohydrin and epibis-type epoxy synthesized from bisphenol A or bisphenol F and its ethylene oxide or propylene oxide modified products. Resin, epoxy novolak resin, phenol, biphenol, etc. and (methyl)
Reaction products with epichlorohydrin, aromatic epoxy resins such as glycidyl ester of terephthalic acid, isophthalic acid and pyromellitic acid, and (poly) ethylene glycol,
Glycols such as (poly) propylene glycol, (poly) butylene glycol, (poly) tetramethylene glycol, neopentyl glycol, and polyglycidyl ethers of alkylene oxide modified products thereof, trimethylolpropane, trimethylolethane, glycerin, diglycerin , Erythritol, pentaerythritol,
Aliphatic polyhydric alcohols such as sorbitol, 1,4-butanediol and 1,6-hexanediol, and glycidyl ethers of alkylene oxide-modified glycidyl ethers and glycidyls of carboxylic acids such as adipic acid, sebacic acid, maleic acid and itaconic acid Esters, glycidyl ethers of polyester polyols of polyhydric alcohols and polycarboxylic acids, copolymers of glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate, glycidyl esters of higher fatty acids, epoxidized linseed oil, epoxidized soybean oil Epoxidized castor oil, aliphatic epoxy resins such as epoxidized polybutadiene, and the like, but are not limited thereto.

The maleimide derivative represented by the general formula (1) is used in a printing ink at 10 to 60% by weight, and other compounds having an average number of functional groups of 4 to 6 having an acryloyl group or a methacryloyl group of 15 to 65% are used. % By weight of the photopolymerization initiator in the range of 2 to 5% by weight. Printing inks include lithographic inks, letterpress inks, flexographic inks, gravure inks, screen inks, coating agents and the like. Among them, lithographic printing ink, clear, OP varnish and the like are particularly preferably used, but are classified into two types depending on the presence or absence of a pigment.

In a system containing a pigment as an essential component, the compound represented by the general formula (1) must be used in an amount of 10 to 30% by weight. When the amount of the compound represented by the general formula (1) is less than 10% by weight, a problem such as a bad smell arises because the photopolymerization initiator is frequently used. On the other hand, when the content exceeds 30% by weight, the strength of the cured coating film is reduced, so that the adhesiveness is deteriorated and the solvent resistance is also deteriorated. The compound containing a 4- to 6-functional acryloyl group or methacryloyl group needs to be used at 15 to 50% by weight. If the amount of the compound containing a 4- to 6-functional acryloyl group or methacryloyl group is less than 15% by weight, the strength of the cured coating film is low, so that the adhesiveness is poor and the solvent resistance is also poor. On the other hand, if it exceeds 50% by weight, the flexibility becomes poor. It is necessary to use the photopolymerization initiator at 2 to 5% by weight. If the amount of the photopolymerization initiator is less than 2% by weight, the curing speed becomes slow, and if it exceeds 5% by weight, odor is generated. More preferably, the compound represented by the general formula (1) is 20 to 30% by weight, the compound having a hexafunctional acryloyloxy group or methacryloyl group is 20 to 36% by weight, and the photopolymerization initiator is 3 to 5% by weight. % Is desirable in consideration of curability, solvent resistance, adhesion, and odor.

In a system in which the pigment is not dispersed, it is necessary to use the compound represented by the general formula (1) at 30 to 60% by weight. When the amount of the compound represented by the general formula (1) is less than 30% by weight, problems such as offensive odor and color burn occur due to heavy use of a photopolymerization initiator. On the other hand, if it exceeds 60% by weight, the strength of the cured coating film will be low and the adhesiveness will be poor,
Solvent resistance also deteriorates. The compound containing a 4- to 6-functional acryloyl group or methacryloyl group must be used in an amount of 35 to 65% by weight. If the amount of the compound containing a 4- to 6-functional acryloyloxy group or methacryloyloxy group is less than 35% by weight, the strength of the cured coating film is low, so that the adhesiveness is poor and the solvent resistance is also poor. On the other hand, if it exceeds 65% by weight, the flexibility will be poor. It is necessary to use the photopolymerization initiator at 2 to 5% by weight. If the photopolymerization initiator is less than 2% by weight, the curing speed becomes slow,
If the content is more than 10% by weight, a bad smell is generated and a color burn occurs. More preferably, the compound represented by the general formula (1) is 40 to 60% by weight, the compound having a 4- to 6-functional acryloyloxy group or methacryloyl group is 35 to 65% by weight, and the photopolymerization initiator is 3 to 65% by weight. It is desirable to contain 5% by weight in consideration of curability, solvent resistance, adhesion, odor, and color burn.

In the present invention, the compound having four or more functional acryloyl groups or methacryloyl groups will be described. Specific examples of the compound having four or more functional acryloyl groups or methacryloyl groups that can be used in the present invention include: (C-1): (poly) ester (meth) acrylate, (C-2): (poly) Ether (meth) acrylate, (C-3): alkyl (meth) acrylate or alkylene (meth) acrylate, (C-4): (meth) acrylate having an aromatic ring, and the like, but are not limited thereto. is not.

(C-1): (Poly) ester (meth) acrylate is a general term for (meth) acrylate having one or more ester bonds in the main chain.
2): (Poly) ether (meth) acrylate is a general term for acrylates having one or more ether bonds in the main chain, and (C-3): alkyl (meth) acrylate or alkylene (meth) acrylate is mainly (C-4): aromatic as a general term for acrylates whose chain is a straight-chain alkyl, branched alkyl, straight-chain alkylene group or branched alkylene group, and which may have a halogen atom and / or a hydroxyl group in a side chain or terminal. A (meth) acrylate having a ring is used as a generic term for a (meth) acrylate having an aromatic ring in a main chain or a side chain.

Each of the compounds is illustrated below, but it should not be construed that the invention is limited thereto. (C-1) As the (poly) ester (meth) acrylate, cyclic lactone compounds such as pentaerythritol or 4 mol or more of ε-caprolactone, γ-butyrolactone, δ-valerolactone or methylvalerolactone per 1 mol of ditrimethylolpropane Tetra (meth) acrylate of triol obtained by adding a cyclic lactone compound such as ε-caprolactone, γ-butyrolactone, δ-valerolactone or methylvalerolactone to 4 mol of dipentaerythritol. Triols such as tetra (meth) acrylate of triol, tetra (meth) acrylate of polyhydric alcohol such as tetraol, pentaol or hexaol;

(C-2) Examples of the (poly) ether (meth) acrylate include a copolymer of ethylene oxide and propylene oxide, a copolymer of propylene glycol and tetrahydrofuran, a copolymer of ethylene glycol and tetrahydrofuran, polyisoprene glycol, Hydrogenated polyisoprene glycol, polybutadiene glycol,
Tetra (meth) acrylates derived from hydrocarbon-based polyols such as hydrogenated polybutadiene glycol; polyhydric hydroxyl compounds such as polytetramethylene hexaglyceryl ether (tetrahydrofuran-modified hexaglycerin); and (meth) acrylic acid; 4 moles per mole of erythritol or ditrimethylolpropane, 4 moles per mole of triol obtained by adding 4 moles or more of a cyclic ether compound such as ethylene oxide, propylene oxide, butylene oxide and / or tetrahydrofuran Triols such as tetra (meth) acrylate of triols obtained by adding the above cyclic ether compounds such as ethylene oxide, propylene oxide, butylene oxide and / or tetrahydrofuran Examples include, but are not limited to, monofunctional (poly) ether (meth) acrylates or polyfunctional (poly) ether (meth) acrylates of polyhydric alcohols such as tetraol, pentaol, and hexaol. .

(C-3) Examples of the alkyl (meth) acrylate or alkylene (meth) acrylate include glycerin tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate and di (meth) acrylate. Triols such as tetra (meth) acrylate of pentaerythritol, tetra (meth) acrylates of polyhydric alcohol such as tetraol and hexaol;

As the compound having an acryloyl group or a methacryloyl group, in addition to the above-mentioned compounds, for example,
Poly (meth) acrylic (meth) acrylate such as a reaction product of (meth) acrylic acid polymer and glycidyl (meth) acrylate or a reaction product of glycidyl (meth) acrylate polymer and (meth) acrylic acid; dimethylaminoethyl (meth) ) Amino group-containing (meth) acrylates such as acrylates; isocyanuric (meth) acrylates such as tris ((meth) acryloxyethyl) isocyanurate; phosphazenes such as hexakis [((meth) acryloyloxyethyl) cyclotriphosphazene] (Meth) acrylate; (meth) acrylate having a polysiloxane skeleton; polybutadiene (meth) acrylate; melamine (meth) acrylate, and the like can also be used. Among these compounds having an acryloyl group or a methacryloyl group, a compound having 4 to 6 acryloyl groups or methacryloyl groups in one molecule is preferable.

The photopolymerization initiator used for curing the radiation-curable printing ink composition of the present invention is a radical polymerization initiator, and these are mainly classified into two types: an intramolecular bond cleavage type and an intramolecular hydrogen abstraction type. Can be different.

Examples of the intramolecular bond cleavage type radical polymerization initiator include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, and 1- (4-isopropylphenyl). ) -2-Hydroxy-2-methylpropane-
1-one, 4- (2-hydroxyethoxy) phenyl-
(2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenyl ketone, 2-methyl-2
-Morpholino (4-thiomethylphenyl) propane-1
-One, 2-benzyl-2-dimethylamino-1- (4
Acetophenones such as -morpholinophenyl) -butanone; benzoins such as benzoin, benzoin methyl ether and benzoin isopropyl ether; 2,4,6
Acylphosphine oxides such as acylphosphine oxides such as trimethylbenzoindiphenylphosphine oxide; benzyl, methylphenylglyoxyester and the like.

Examples of the intramolecular hydrogen abstraction type radical polymerization initiator include, for example, benzophenone, methyl-4-phenylbenzophenone o-benzoylbenzoate,
4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenylsulfide, acrylated benzophenone, 3,3 ', 4
Benzophenones such as 4'-tetra (t-butylperoxycarbonyl) benzophenone and 3,3'-dimethyl-4-methoxybenzophenone; 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4
Thioxanthones such as diethylthioxanthone and 2,4-dichlorothioxanthone;
Aminobenzophenones such as 4'-diethylaminobenzophenone;10-butyl-2-chloroacridone;
-Ethylanthraquinone, 9,10-phenanthrenequinone, camphorquinone and the like.

As components which can be used in combination with the radiation-curable printing ink composition of the present invention, it is possible to appropriately use materials used in conventional ultraviolet or electron beam-curable inks, OP varnishes and clears. An example is shown below.

Organic pigments, inorganic pigments and inorganic extenders as colorants, viscosity modifiers and extenders. As extenders, C
ACO _3, MgCO _3, talc, clay and the like are used.
As a thermal polymerization inhibitor to prevent the aging of the ink, use of hydroquinone and other hardened inks, various waxes to improve the strength and slipperiness of the OP varnish and clear film, silicone oils, photocuring reaction Saturated polyesters and the like are mentioned as a photosensitizer for performing more effectively and a resin that can be used in combination.

When the radiation-curable printing ink composition of the present invention is applied to a lithographic printing ink, OP varnish or clear, it is instantaneously cured and dried by irradiating ultraviolet rays or an electron beam.
Excellent printed matter without rub resistance, solvent resistance, adhesion, and color burn can be obtained.

The standard ultraviolet curing conditions are as follows:
The line speed is 5 to 50 m / min by using an ultraviolet irradiation device having a 60 W / cm high-pressure mercury or metal halide lamp. In the case of electron beam curing, for example, an electron curtain electron beam irradiation device manufactured by Iwasaki Electric Co., Ltd.
Irradiation of 1 to 6 megarads in an oxygen concentration atmosphere of 00 ppm or less is desirable.

[0048]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the scope of these Examples.

First, a method for synthesizing the maleimide derivative A used in all Examples will be described. In a 200 ml eggplant-shaped flask equipped with a Dean-Stark fractionator, polytetramethylene glycol having a number average molecular weight of 1,000 ("PTGL100" manufactured by Hodogaya Chemical Co., Ltd.) was added.
0 ", polystyrene equivalent value by gel permeation chromatography (hereinafter abbreviated as GPC): number average molecular weight 2,100, weight average molecular weight 5.00
0) 20 g, maleimidocaproic acid 9.8 g, p-toluenesulfonic acid 1.2 g, 2,6-tert-butyl-
0.06 g of p-cresol and 15 ml of toluene were charged, and the reaction was continued while stirring for 4 hours while removing water generated under the conditions of 240 torr and 80 ° C. The reaction mixture was dissolved in 200 ml of toluene, and washed three times with 100 ml of saturated sodium hydrogen carbonate and once with 100 ml of saturated saline. The organic phase was concentrated to synthesize the maleimide derivative A.

The obtained maleimide derivative A is used as a compound having 4- and 6-functional acryloyloxy groups.
ETTA, DPHA, Irgacure 184 as a photopolymerization initiator, and saturated polyester, talc, wax, etc. were added to adjust the ink and clear. The formulations and evaluation results are shown in Tables 1 to 6. Tables 1 and 2 show Examples of a pigment dispersion system (ink), Table 3 shows Examples of a pigment dispersion system (OP varnish), Table 4 shows Examples of a system containing no pigment (clear), and Tables 5 and 6 show Comparative Examples.

The test methods for curability, solvent resistance, adhesion, odor, and color burn are as follows.

(1) UV curability Pigment dispersion system (ink): 0.2 c of ink in dropper
c (ink spreading amount: 2.5 g / m2), and the composition was spread on polyester tack paper by an RI tester (manufactured by Hoei Seiko Co., Ltd.). The developed product was used as a 120 W / cm metal halide lamp (manufactured by Eye Graphics Co., Ltd.).
The composition having a curing speed of 40 m / min or more was designated as curable “○”, and the ink having a curing speed of 50 m / min or more was designated as “◎”. -Pigment dispersion system (OP varnish): 0.2 ink in dropper
cc (2.5 g / m2 of ink spread color) was applied to an art paper with an RI tester (manufactured by Hoei Seiko Co., Ltd.) and cured to obtain a raw material. OP varnish 0.2cc
(OP varnish coloring amount of 2.5 g / m2) was colored with an RI tester. The developed product was cured with a 120 W / cm metal halide lamp (manufactured by I-Graphics Co., Ltd.) when the curing speed was 40 m / min or more, and the ink was cured when the curing speed was 40 m / min or more and the curing speed was 50 m / min or more. The property was evaluated as “◎”. A system in which the pigment is not dispersed (clear): 0.2 cc of black ink is applied to the dropper (ink spread amount: 2.5 g / m2), and is spread on art paper with an RI tester (manufactured by Hoei Seiko Co., Ltd.). The cured material was used as the raw material. 0.4 cc of a clear material (clear coating amount 5 g / m 2) was applied to the raw material with an RI tester. The developed product was cured with a 120 W / cm metal halide lamp (manufactured by Eye Graphics Co., Ltd.) to cure when the curing speed was 40 m / min or more, and to cure the clear when the curing speed was 50 m / min or more. The property was evaluated as “◎”.

(2) Solvent resistance The cured coating film was rubbed with absorbent cotton impregnated with MEK (methyl ethyl ketone) to make the ink, OP varnish and clear that the coating film was peeled off in 50 times or less.

(3) Adhesive Ink, OP, whose cured coating film can be peeled off with cellophane tape
The varnish and clear were regarded as having poor adhesion.

(4) Gloss Dropper with 0.2 cc of black ink (ink spread 2.5
g / m2), RI tester (manufactured by Hoei Seiko Co., Ltd.)
It was used as a raw material after being colored on art paper and cured. 0.4cc of clear material (clear coating amount 5g / m
2) was colored with an RI tester. 120
It was cured by passing through a W / cm metal halide lamp (manufactured by Eye Graphics Co., Ltd.). Then, the gloss of the cured coating film was measured with a Macbeth gloss meter.

(5) Odor The ink containing 6% of a photopolymerization initiator, the OP varnish and the clear having a lower odor than when the OP varnish and the clear were hardened were regarded as having no odor.

(6) Color Burn A composition containing no pigment and having higher whiteness than a cured coating film of a radiation-curable composition containing 6% of a photopolymerization initiator was evaluated as having no color burn.

[0058]

[Table 1]

[0059]

[Table 2]

[0060]

[Table 3]

[0061]

[Table 4]

[0062]

[Table 5]

[0063]

[Table 6]

Each composition in the table shows the following. Yellow pigment:
SYMULER FAST Y made by Dainippon Ink and Chemicals, Inc.
ELLOW GTF235-D Red pigment: SY. BRILLIA
NT CARMINE6B 320 Indigo pigment: FASTOGEN B manufactured by Dainippon Ink and Chemicals, Inc.
LUE TGR-A carbon black: carbon raben 106 manufactured by Mitsubishi Chemical
0 CaCO3: SA300 manufactured by Takehara Chemical Saturated polyester: saturated polyester consisting of trimethylolpropane and isophthalic acid Wax: polyethylene wax manufactured by Nippon Seisaku PETA: Alonix M-305 (pentaerythritol triacrylate) manufactured by Toago PETA: Aronix M manufactured by Toagosei -450 (pentaerythritol tetraacrylate) DPHA: Alonix M-400 (dipentaerythritol tetraacrylate) manufactured by Toagosei Initiator: Irgacure 184 (1-hydroxycyclohexylphenyl ketone) manufactured by Ciba Geigy Silicon: SH-28P. Manufactured by Toray A.

[0065]

The radiation-curable printing ink composition of the present invention can be cured with practical light intensity and light irradiation amount while minimizing problems such as bad smell and color burn, and the cured film strength can be reduced. high.

Continued on the front page (72) Inventor Atsushi Miyagawa 2-3-1 Miyugaoka, Yotsukaido-shi, Chiba (72) Miya Inventor 1-28-A-212, Osakidai, Sakura-shi, Chiba F-term (reference) 4J011 QA04 QA19 QA39 QB12 QB14 QB16 QB19 QB24 QB29 QC07 RA04 RA11 SA90 TA03 UA01 WA05 4J039 AD21 AE04 AE05 AE06 AE07 AF04 AF05 AF07 BE27 CA01 EA04 EA06 EA08 EA10 EA35 EA36 EA39 EA43 GA02 GA25

Claims (5)

[Claims] 1. Compounds 10 to 6 represented by the general formula (1)
A radiation-curable printing ink comprising, as essential components, 0-wt%, 15-65 wt% of a compound having an acryloyl group or a methacryloyl group having an average number of functional groups of 4-6 and 2-5 wt% of a photopolymerization initiator. Composition. Embedded image (In the formula, m and n each independently represent an integer of 1 to 5, and m + n is 6 or less. X1, Y1, X2, and Y
2 each independently represents hydrogen or an alkyl group. R
11 and R12 are each independently an alkylene group,
Represents a hydrocarbon bond selected from the group consisting of a cycloalkylene group, an arylalkylene group and a cycloalkylalkylene group. G1 and G2 each independently represent an ester bond or a urethane bond. R2 is a group in which at least one organic group selected from the group consisting of a linear alkylene group, a branched alkylene group, an alkylene group having a hydroxyl group, a cycloalkylene group, an aryl group and an arylalkylene group is (a) an ether bond; An average molecular weight of 100 to 100 linked by at least one bond selected from the group consisting of an ester bond and (c) a urethane bond.
100,000 (A) (poly) ether tethers,
(B) represents a (poly) ester linked chain or (C) (poly) urethane linked chain. ) 2. In the general formula (1), G1 and G2 are each independently an ester bond represented by —COO— or —OCO—, and R2 is a linear alkylene group, a branched alkylene group, At least one organic group selected from the group consisting of an alkylene group having a hydroxyl group, a cycloalkylene group, an aryl group and an arylalkylene group is at least one bond selected from the group consisting of (a) an ether bond and (b) an ester bond. The radiation-curable printing ink composition according to claim 1, which is a linked (A) (poly) ether linked chain or (B) (poly) ester linked chain having an average molecular weight of 100 to 100,000. 3. A compound represented by the general formula (1):
Compounds 35 to 6 having an acryloyloxy group or a methacryloyloxy group having an average functional group number of 4 to 60% by weight,
The radiation-curable printing ink composition according to claim 1, comprising 5% by weight and 2 to 5% by weight of a photopolymerization initiator as essential components. 4. Compounds 10 to 3 represented by the general formula (1)
0 to 15% by weight, compounds having an average number of functional groups of 4 to 6 and having an acryloyloxy group or a methacryloyloxy group of 15 to 50
The radiation-curable printing ink composition according to claim 1, which contains, as essential components, 2% by weight, 2 to 5% by weight of a photopolymerization initiator, and a pigment. 5. The compound having an acryloyloxy group or a methacryloyloxy group is (A-1) (poly) ester (meth) acrylate, (A-2) urethane (meth) acrylate, (A-3) epoxy (meth) ) Acrylate, (A-4) (poly) ether (meth) acrylate, (A-5) alkyl (meth) acrylate or alkylene (meth) acrylate, (A-6) (meth) acrylate having an aromatic ring, and (A -7) The radiation-curable printing ink composition according to any one of claims 1 to 4, which is at least one compound selected from the group consisting of (meth) acrylates having an alicyclic structure.