JP2001348516A - Resin composition for active energy ray curing type ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an active energy ray curing type resin composition capable of improving the curability and chemical resistance possessed by an active energy ray curing type ink and having printability such as pigment dispersibility, fluidity, scumming properties and emulsification suitability required by a printing ink. SOLUTION: This active energy ray curing type resin composition is obtained by using (A) a resin prepared by modifying (a1) a saturated polyester of a monobasic acid, a polybasic acid and a polyhydric alcohol with (a2) a urethane acrylate having an isocyanate group and (B) bi- or polyvalent (meth)acrylates.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable ink resin composition which is quick-drying and excellent in printability. The resin composition for an active energy ray-curable ink according to the present invention provides a resin composition for an ink which is excellent in wetting with a pigment, various flow properties as an ink vehicle, curability, and emulsification suitability, and particularly suitable for offset printing. I do.

[0002]

2. Description of the Related Art Conventionally, as an offset ink, a resin composition for a high-viscosity ink containing a varnish obtained by dissolving a rosin-modified phenol resin, a rosin maleic acid resin, and a vegetable oil-modified alkyd resin in a high-boiling petroleum solvent has been used. . In general, the inks using them dry slowly and the abrasion resistance and solvent resistance of the printed matter are not sufficient because the ink vehicle is thermoplastic. On the other hand, offset rotary printing has a drawback in that a large amount of equipment cost is required since equipment such as a drying equipment for forced drying and cooling rollers is required.

In order to improve such disadvantages, various active energy ray-curable vehicles have been developed and put into practical use as resin compositions for inks. Specifically, a method using epoxy acrylate, urethane acrylate, polyester acrylate, etc., for example, in JP-A-5-320555, a method in which a saturated polyester obtained from a monobasic acid, a polybasic acid and a polyhydric alcohol is used as (meth) acrylates An active energy ray-curable ink composition using a resin obtained by dissolution is disclosed. However, these conventional resin compositions for active energy ray-curable inks have poor gel elasticity, and cannot be said to have sufficient printability such as ink fluidity and ground stain resistance. Further, the conventional resin composition has a disadvantage that the wettability with the pigment is inferior, and the gloss of the ink is hardly obtained. In addition, polydiallyl phthalate resin (DAP)
Inactive inert polymers are also used for active energy rays such as resin. These are often used as an ink varnish by dissolving an acrylate monomer or a methacrylate monomer as necessary. However, when an inert resin such as a DAP resin is used, since the (meth) acryloyl group is not chemically bonded to the resin, the durability of the ink film after curing, such as surface curability and friction resistance, is improved. Sex is not enough.

[0004]

The problem to be solved by the present invention is to improve the curability and chemical resistance of the active energy ray-curable ink, and to improve the pigment dispersibility and fluidity required for the printing ink. An object of the present invention is to provide a resin composition for an active energy ray-curable ink which has printability such as water resistance, background stain resistance and emulsification suitability.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies on a method for improving the curability and improving the printability without impairing the properties of the active energy ray-curable ink. As a result, the saturated polyester (a1) was obtained. (A) modified with a urethane acrylate (a2) having an isocyanate group, and a 2- to 5-functional (meth) acrylate (B)
By using the ink varnish obtained by the above, it is found that the ink has excellent printability such as ink fluidity and emulsification suitability, and has excellent durability such as curability after printing and abrasion resistance, thereby completing the present invention. Reached.

That is, the present invention relates to a saturated polyester (a
The present invention relates to a method for producing a resin for an active energy ray-curable ink in which 1) is modified with a urethane acrylate (a2) having an isocyanate group. The present invention also includes a method for producing a resin for an active energy ray-curable ink, which is a saturated polyester comprising a polyhydric alcohol as an essential component. Monobasic acid to total acid component 3
The present invention includes a method for producing a resin set for an active energy ray-curable ink which is a saturated polyester using 0 to 80 mol%, and the present invention has a saturated polyester (a1) having an oil length of 30% or less. The present invention also includes a method for producing a resin set for an active energy ray-curable ink, and the present invention provides an active energy wherein the urethane urethane acrylate (a2) having an isocyanate group has an aromatic ring structure and / or an alicyclic structure. The present invention includes a method for producing a line-curable resin, and the present invention provides a method for producing an isocyanate-containing urethane acrylate (a2) having an isocyanate group (NCO) and a saturated polyester (a1) having a hydroxyl group (O1).
H) includes a method for producing a resin for an active energy ray-curable ink having an equivalent ratio (NCO / OH) of 0.1 to 1.0, and the present invention is obtained by the above method. The present invention includes a resin composition for an active energy ray-curable ink obtained by dissolving a resin (A) for an active energy ray-curable ink in a bifunctional or higher functional (meth) acrylate (B). Active energy ray curing wherein the bifunctional or higher (meth) acrylates (B) are 2 to 5 functional (meth) acrylates and the bifunctional (meth) acrylate content is 70% by weight or more. It contains a resin composition for mold ink.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The resin (A) used in the present invention is obtained by modifying a saturated polyester (a1) with a urethane acrylate (a2) having an isocyanate group. As the saturated polyester (a1), those obtained by using a dibasic acid and a dihydric alcohol as essential components are preferable. If necessary, a monobasic acid, a tribasic or higher polybasic acid, and a trihydric or higher polyhydric alcohol are used. be able to. In order to sufficiently obtain the effects of improving the curability, emulsification suitability, abrasion resistance, solvent resistance, chemical resistance, etc. of the ink, the isocyanate group (NCO) equivalent of urethane acrylate and the saturated polyester (a1) in the modification by (a2) Of hydroxyl group (OH) equivalent to (NCO / O
H) is preferably from 0.1 to 1.0, and more preferably from 0.4 to 1.0.
A range of 1.0 is particularly preferred. The weight average molecular weight of the resin (A) is preferably in the range of 1000 to 225000, and particularly preferably in the range of 1500 to 150,000.

As the saturated polyester (a1), a monobasic acid is used as the acid component in an amount of 30 to 80 mol%, preferably 35 to 70 mol% of the total acid component. If it is at most 30 mol%, the viscoelasticity and fluidity of the ink will decrease, and printability will decrease.

Further, the saturated polyester (a1) has an oil length of 30% or less. If the oil length exceeds 30%, the printability such as curability and ground stain resistance deteriorates, which is not preferable. The acid value of the saturated polyester (a1) is usually preferably in the range of 0.1 to 80 (KOH mg / g).
A range of 50 to 50 (KOH mg / g) is particularly preferred.

The method for producing the saturated polyester (a1) is not particularly limited, and methods such as direct esterification such as bulk polymerization and solvent polymerization and transesterification can be applied. Urethane acrylate having isocyanate group (a2)
The reaction temperature for denaturation by urethane and urethane modification is 40 to 95.
C is preferred.

The monobasic acids used as necessary to obtain a saturated polyester can be roughly classified into fatty acids and monobasic acids other than fatty acids, and it is preferable to use monobasic acids excluding fatty acids. Representative examples of monobasic acids excluding fatty acids include fatty acids, abietic acid, hydrogenated abietic acid, benzoic acid, para-tert-butylbenzoic acid, caproic acid and the like.

The fatty acid component in the monobasic acid includes
Those having 5 to 30 carbon atoms are preferred, and among them, those having 10 to 20 carbon atoms are particularly preferred. Further, it is preferably a linear or branched saturated or unsaturated carboxylic acid. Representative examples include linseed oil fatty acids, soybean oil fatty acids, safflower oil fatty acids, castor oil fatty acids, kiri oil fatty acids, tall oil fatty acids, lauric acid, tridecyl acid, myristic acid, pentadecyl acid, palmitic acid, heptadecyl acid. And fatty acids such as stearic acid, isostearic acid, nonadecanoic acid, oleic acid, elaidic acid, and setreic acid. These fatty acids can be used alone or in combination of two or more.

Typical examples of the dibasic acid used to obtain the saturated polyester (a1) are terephthalic acid, isophthalic acid, (phthalic anhydride), trimellitic acid (anhydride), Meritic acid, 2,6
Saturated dibasic acids such as naphthalenedicarboxylic acid, 5-sodium sulfoisophthalic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecandionic acid, 1,4-cyclohexanedicarboxylic acid, hexahydro (anhydride) phthalic acid; Anhydride) maleic acid, fumaric acid, itaconic acid,
Unsaturated dibasic acids such as tetrahydro (anhydride) phthalic acid; dodecenyl (anhydride) succinic acid; tetrahydro (anhydride) phthalic acid; These acids can be used alone or in combination.

Typical examples of the dihydric alcohol used for obtaining the saturated polyester (a1) include:
Ethylene glycol, propylene glycol, 1,3-
Butanediol, 1,4-butanediol, 1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, Propylene glycol, tripropylene glycol, tetramethylene glycol having an average molecular weight of 200 to 4000, 1,4-cyclohexanediol, ethylene oxide and propylene oxide adduct of bisphenol A, ethylene oxide and propylene oxide adduct of hydrogenated bisphenol A, 1, 4-
Cyclohexane dimethanol and the like.

Representative examples of polyhydric alcohols include glycerin having three or more functional groups, trimethylolethane, trimethylolpropane, tris-2-hydroxyethylisocyanurate, pentaerythritol, dipentaerythritol, sorbitol and the like. Is mentioned. The use of a polyhydric alcohol is particularly preferred because it increases the degree of resin branching and has a positive effect on the viscoelasticity of the ink. These dihydric alcohols and polyhydric alcohols can be used alone or in combination of two or more.

The saturated polyester (a1) may be epoxy-esterified with a polyepoxide. Examples of the polyepoxide to be used include aliphatic ether diepoxides such as ethylene glycol di (methyl) glycidyl ether and polypropylene glycol di (methyl) glycidyl ether; and ester diepoxides such as di (methyl) glycidyl phthalate and di (methyl) glycidyl tetrahydrophthalate. Etc. can be used. In particular, it is preferable to use a bisphenol type diepoxide which is a reaction product of (methyl) epichlorohydrin and bisphenol A.

The modification of the saturated polyester (a1) with the urethane acrylate (a2) having an isocyanate group may be carried out immediately after the reaction of the saturated polyester (a1), or the modification of the saturated polyester (a1) with the (meth) acrylates (B). It may be performed after mixing. The mixture of the (meth) acrylates (B) is a saturated polyester (a1)
After the reaction and after the (a1) is modified with the urethane acrylate (a2) having an isocyanate group, the mixture can be divided into two and mixed.

Examples of the urethane acrylate (a2) having an isocyanate group include those obtained by reacting a (meth) acrylate (C) having a hydroxyl group with an isocyanate compound (D).
In the reaction between (C) and (D), the equivalent ratio (NCO / OH) of the isocyanate group (NCO) of (D) and the hydroxyl group (OH) of (C) is preferably in the range of 0.1 to 1.0. ,
Especially, the range of 0.5 to 1.0 is particularly preferable. Also,
The isocyanate compound (D) preferably has an aromatic ring structure and / or an alicyclic structure, which increases the bulk of the resin and is preferable in printability.

The (meth) acrylates (C) having a hydroxyl value are not particularly limited, and any of them can be used.
Typical examples thereof include 2-hydroxyethyl (meth) acrylate and caprolactone-modified 2-
Examples include hydroxyethyl (meth) acrylates, glycerol (meth) acrylate, glycerol dimethacrylate, 2-hydroxypropyl acrylate, pentaerythritol triacrylate, epochlorohydrin-modified phenoxy acrylate, polyethylene glycol methacrylate, and epoxy acrylates. .

As the isocyanate compound (D), any of various aliphatic, aromatic or alicyclic dissocyanate monomers and triisocyanate monomers can be used. Typical examples thereof include tolylene diisocyanate, hydrogenated tolylene diisocyanate,
Diphenylmethane-4,4'-diisocyanate, hydrogenated diphenylmethane-4,4'-diisocyanate, 1,
4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, xylene diisocyanate, trimethyl xylene diisocyanate, hydrogenated xylene diisocyanate, 1,5-naphthalene diisocyanate, 1,3-bis (α, α-dimethyl isocyanatomethyl) benzene, cyclohexyl -1,4-diisocyanate, oxadiazinetrione diisocyanate,
Examples include isophorone diisocyanate, triphenylmethane diisocyanate, norbornene diisocyanate, and the like. These can be used alone or in combination of two or more.

The amount of the bifunctional or higher functional (meth) acrylates (B) that dissolve the resin (A) is determined according to JIS.
It can be determined by measurement using a K5400 Gardner viscometer. The viscosity of the measurement sample such that the weight ratio [(A) + (B)] / (butyl acetate) is 4/1 is from U to U.
It is preferable to add the (meth) acrylates (B) so as to obtain Z and determine the blending amount.

At this time, the amount of the (meth) acrylates (B) that dissolve the resin (A) is preferably 20 to 80% by weight based on the total amount of (A) and (B). The dissolution temperature is preferably in the range of 80 to 120 ° C, and is equal to or lower than the polymerization temperature of (meth) acrylates (B) and urethane acrylate.
It is necessary that the temperature is lower than the decomposition temperature and lower than the polymerization temperature of the fatty acid.

The (meth) acrylates (B) used in the present invention preferably include the (meth) acrylates (B1) used for urethane acrylate. Further, it is preferable to use a bifunctional (meth) acrylate as an essential component, and to use a bifunctional or more, preferably 2 to 5 functional (meth) acrylate in combination, if necessary.

A typical example of (meth) acrylate (B1) is ethylene glycol di (meth).
Acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate,
1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, neopentyl glycol hydroxypivalate di (meth) acrylate, bisphenol A ethylene oxide adduct di (meth) acrylate, bisphenol A Di (meth) acrylate of propylene acid adduct, 2,
Bifunctional (meth) acrylates such as di (meth) acrylate of 2'-di (hydroxypropoxyphenyl) propane and di (meth) acrylate of tricyclodecane dimethylol; morpholine acrylate, N-vinylpyrrolidone, N- Bifunctional (meth) acrylates such as vinyl formamide and EO-modified phosphoric acid (meth) acrylate;

Trimethylolpropane tri (meth) acrylate, ditrimethylolpropanetetra (meth) acrylate, trimethylolethanetri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tetramethyloltetra (Meth) acrylate,
Glycerin (meth) acrylate, tris ((meth)
(Acryloxyethyl) isocyanurate; and polyfunctional acrylates such as acrylic acid ester of a polyol obtained by ring-opening addition of ethylene oxide and propylene oxide thereto. These alone,
Two or more types can be used in combination.

The active energy ray-curable ink composition of the present invention preferably contains a photoinitiator and a photosensitizer. As a photoinitiator and a photosensitizer that can be used in the present invention, a photoinitiator and a photosensitizer used in an ordinary active energy ray-curable resin composition can be used.

As typical examples of the photoinitiator,
Acetophenones, benzophenone, Michler's ketone,
Benzyl, benzoin ethers, benzyl dimethyl ketal, α-acyloxime esters, thioxanthones, anthraquinones and derivatives thereof, acylphosphine oxides and derivatives thereof, and the like.

Typical examples of the photosensitizer include amines, ureas, sulfur compounds, nitriles, phosphorus compounds, nitrogen compounds, chlorine compounds and the like. These photoinitiators or photosensitizers can be used alone or in combination of two or more. The amount used is resin 1
0.5 to 45 parts by weight is preferable with respect to 00 parts by weight,
Among them, 2 to 20 parts by weight is particularly preferable.

In the present invention, for the purpose of enhancing suitability as a printing ink, any resin which does not contain an oligomer or a double bond can be appropriately used. Representative examples include epoxy acrylate, polyester acrylate, urethane acrylate, rosin-modified epoxy acrylate, fatty acid-modified epoxy acrylate, polydiallyl phthalate resin, amino resin, benzoguanamine resin, alkyd resin, petroleum resin, and the like.

The resin composition for an active energy ray-curable resin ink of the present invention preferably contains a thermal polymerization inhibitor in order to prevent thermal polymerization during production and maintain storage stability. Typical examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, t
-Butylcatechol, p-benzoquinone, 2,5-t-
Butylhydroquinone, phenothiazine and the like. The amount is preferably 0.01 to 1% by weight based on the weight of the resin. Known and used colorants, pigments, surface smoothing agents, defoamers, viscosity modifiers and the like can be added to the resin composition of the present invention.

The resin composition for an active energy ray-curable ink of the present invention is printed on a substrate, for example, paper, film, sheet or the like, by a usual printing method or coating method, and then the active energy ray is applied. Irradiate and cure. For curing, for example, a low-pressure or high-pressure mercury lamp, a metal halide lamp, a xenon lamp, an electrodeless discharge lamp, a carbon arc lamp and the like can be used. The standard curing conditions are a line speed of 5 to 80 m / min per lamp by an ultraviolet irradiation device using a high-pressure mercury lamp or a metal halide lamp having an output of 80 to 300 W / cm.

【Example】

Next, the present invention will be described with reference to examples.
The present invention is not limited only to the embodiments. Parts and% in the examples are by weight unless otherwise specified.

Synthesis Example 1 (Preparation of Urethane Acrylate Having Isocyanate Group 1) 298 parts of pentaerythritol triacrylate having a hydroxyl value of 188 and 223 parts of isophorone diisocyanate
The reaction was carried out at 0 ° C. for 5 hours to obtain a urethane acrylate having an isocyanate group content of 8.1% (hereinafter abbreviated as NCO content) (a2-1).

Synthesis Example 2 (Preparation of urethane acrylate having isocyanate group 2) 116 parts of 2-hydroxyethyl acrylate and 223 parts of isophorone diisocyanate were reacted at 90 ° C. for 5 hours to obtain a urethane acrylate (a2) having an NCO content of 12.4%. -2) was obtained.

Synthesis Example 3 (Preparation 1 of saturated polyester) In the presence of an inert gas, 26 parts of neopentyl glycol,
227 parts of pentaerythritol, 3 parts of adipic acid, 215 parts of isophthalic acid, and 506 parts of benzoic acid are reacted at 220 ° C. for 3 hours to obtain a saturated polyester (a1-1) having an acid value of 8, a hydroxyl value of 13, and a weight average molecular weight of 24,000. I got

Synthesis Example 4 (Preparation 2 of saturated polyester) In the presence of an inert gas, neopentyl glycol 4 parts, pentaerythritol 232 parts, adipic acid 25 parts, isophthalic acid 228 parts, benzoic acid 450 parts, soybean oil fatty acid 1
00 parts was reacted at 220 ° C. for 3 hours, and the solid content acid value was 10,
A saturated polyester (a1-2) having a hydroxyl value of 24 and a weight average molecular weight of 12,000 was obtained.

Synthesis Example 5 (Preparation 3 of saturated polyester) In the presence of an inert gas, 35 parts of neopentyl glycol,
Pentaerythritol 208 parts, isophthalic acid 232
Parts, 350 parts of benzoic acid and 175 parts of dehydrated castor oil fatty acid were reacted at 220 ° C. for 3 hours, and the solid content acid value was 8 and the hydroxyl value was 4
0, a saturated polyester having a weight average molecular weight of 20,000 (a
1-3) was obtained.

Synthesis Example 6 (Preparation of resin for active energy ray-curable ink 1) 54 parts of saturated polyester (a1-1) were dissolved in 40 parts of trimethylolpropane trimethacrylate, and the equivalent ratio (NCO / OH) was 0. By reacting with 6 parts of urethane acrylate (a2-1) having an isocyanate group so as to be 0.92, an active energy ray-curable ink resin was obtained. Hereinafter, this resin is referred to as (A-1). Solution viscosity obtained by diluting (A-1) with butyl acetate is X (Gardner viscometer)
Met.

Synthesis Example 7 (Preparation of resin for active energy ray-curable ink 2) 54 parts of saturated polyester (a1-1) were dissolved in 40 parts of dipentaerythritol hexaacrylate, and the equivalent ratio (NCO / OH) was 0. By reacting with 6 parts of urethane acrylate (a2-1) having an isocyanate group so as to be 0.92, an active energy ray-curable ink resin was obtained. Hereinafter, this resin is referred to as (A-2). The solution viscosity of (A-2) diluted with butyl acetate is Y (Gardner viscometer)
Met.

Synthesis Example 8 (Preparation of resin for active energy ray-curable ink 3) 54 parts of saturated polyester (a1-2) were dissolved in 40 parts of trimethylolpropane trimethacrylate, and the equivalent ratio (NCO / OH) was 0. Then, the mixture was reacted with 6 parts of urethane acrylate (a2-2) having an isocyanate group so as to obtain an active energy ray-curable ink resin. Hereinafter, this resin is referred to as (A-3). The solution viscosity of (A-3) diluted with butyl acetate is U (Gardner viscometer)
Met.

Synthesis Example 9 (Preparation of resin for active energy ray-curable ink 4) 54 parts of saturated polyester (a1-2) were dissolved in 40 parts of dipentaerythritol hexaacrylate, and the equivalent ratio (NCO / OH) was 0. Then, the mixture was reacted with 6 parts of urethane acrylate (a2-2) having an isocyanate group so as to obtain an active energy ray-curable ink resin. Hereinafter, this resin is referred to as (A-4). Solution viscosity of (A-4) diluted with butyl acetate is W (Gardner viscometer)
Met.

Synthesis Example 10 (Preparation of resin for active energy ray-curable ink 5) 50 parts of saturated polyester (a1-3) was dissolved in 40 parts of trimethylolpropane trimethacrylate, and the equivalent ratio (NCO / OH) was 0. With isophorone diisocyanate to give an equivalent ratio (NCO /
(OH) was adjusted to 0.45 to react with 8 parts of urethane acrylate (a2-1) having an isocyanate group to obtain an active energy ray-curable ink resin. Hereinafter, this resin is referred to as (A-5). The solution viscosity obtained by diluting (A-5) with butyl acetate was Z (Gardner viscometer).

Synthesis Example 11 (Preparation of resin for active energy ray-curable ink 6) 50 parts of saturated polyester (a1-3) was dissolved in 40 parts of neopentyl glycol diacrylate, and the equivalent ratio (NCO / OH) was 0. 8 parts of urethane acrylate (a2-1) having an isocyanate group are reacted with saturated polyester (a1-2) so that the equivalent ratio (NCO / OH) becomes 0.50. To obtain an active energy ray-curable ink resin. Hereinafter, this resin is referred to as (A-6).
The solution viscosity of (A-6) diluted with butyl acetate was U (Gardner viscometer).

Synthesis Example 12 (Preparation of resin for active energy ray-curable ink 7) 60 parts of saturated polyester (a1-1) was dissolved in 40 parts of trimethylolpropane trimethacrylate to prepare an active energy ray-curable ink resin. Obtained. Hereinafter, this resin is referred to as (A'-1). The solution viscosity of (A'-1) diluted with butyl acetate was V (Gardner viscometer).

Synthesis Example 13 (Preparation of resin for active energy ray-curable ink 8) 60 parts of saturated polyester (a1-2) was dissolved in 40 parts of dipentaerythritol hexaacrylate to obtain a resin for active energy ray-curable ink. Was. Hereinafter, this resin is referred to as (A'-2). The solution viscosity of (A'-2) diluted with butyl acetate was U (Gardner viscometer).

Synthesis Example 14 (Preparation of resin for active energy ray-curable ink 9) 60 parts of saturated polyester (a1-3) was dissolved in 40 parts of neopentyl glycol diacrylate to obtain a resin for active energy ray-curable ink. Was. Hereinafter, this resin is referred to as (A'-3). Hereinafter, the viscosity of the solution diluted with butyl acetate was V (Gardner viscometer).

Examples 1 to 6 and Comparative Examples 1 to 3 Using the active energy ray-curable ink resin obtained in Synthesis Examples 1 to 9, the active energy was obtained by grinding with a three roll in the following composition. A line-curable ink was obtained. Compounding pigment (carbon black) 13 parts Extender pigment 13 parts Active energy ray-curable ink resin (A) 45 to 50 parts Photoinitiator 8 parts Ditrimethylolpropane tetraacrylate (B) 16 to 21 parts Ink tack value is 13.0 ±
Adjustment was appropriately made in (B) so as to be 0.5, and the ink performance was evaluated. The photoinitiator used was Irgacure 184, 907 manufactured by Nippon Ciba Geigy Co., Ltd. in 5 parts / 5 parts.

[0048]

[Table 1]

* 1) The curability was determined by examining the scratching property of the printed surface with an ultraviolet irradiation device using an air-cooled metal hydride lamp having an output of 80 W / cm. Those having no scratches have good curability. * 2) The degree of misting was visually determined at 1200 rpm with an incometer at a degree to which the ink was scattered around the periphery. The misting property was judged to be inferior as the ink was easily scattered in the form of a mist, and was evaluated. * 3) The emulsification suitability was determined by visually observing the appearance of stains when the ink and water were emulsified on a printing machine. Those which did not easily show dirt were judged to have excellent emulsification suitability.

As is clear from Table 1, the inks of the examples were superior to the inks of the comparative examples in printability such as curability, misting, and emulsification suitability.

[0051]

According to the present invention, there is provided a resin composition for an active energy ray-curable ink having the curability and chemical resistance characteristics of an ultraviolet-curable ink, and having excellent printability such as fluidity and emulsification suitability. Can provide things.

Claims (8)

[Claims] 1. A resin comprising a resin (A) obtained by modifying a saturated polyester (a1) with a urethane acrylate (a2) having an isocyanate group, and a bifunctional or more functional (meth) acrylate (B). Active energy ray-curable resin composition for ink. 2. The active energy ray-curable ink resin composition according to claim 1, wherein the saturated polyester (a1) is a saturated polyester comprising a monobasic acid, a dibasic acid and a polyhydric alcohol as essential components. 3. The resin for an active energy ray-curable ink according to claim 2, wherein the saturated polyester (a1) comprises a monobasic acid other than a fatty acid as an acid component in an amount of 30 to 80 mol% of the total acid component. Composition. 4. The oil length of the saturated polyester (a1) is 3
4. The resin composition for an active energy ray-curable ink according to claim 1, wherein the content is 0% or less. 5. The resin for an active energy ray-curable ink according to claim 1, wherein the urethane acrylate (a2) having an isocyanate group has an aromatic ring structure and / or an alicyclic structure. Composition. 6. An equivalent ratio (N) of an isocyanate group (NCO) of a urethane acrylate (a2) having an isocyanate group and a hydroxyl group (OH) of a saturated polyester (a1).
CO / OH) is 0.1 to 1.0, The resin composition for active energy ray-curable inks according to any one of claims 1 to 5. 7. The resin composition for active energy ray-curable ink (A) obtained by the production method according to claim 1 is a difunctional or higher functional (meth) acrylate (B). A resin composition for an active energy ray-curable ink characterized by being dissolved in water. 8. The bifunctional or higher (meth) acrylates (B) are 2 to 5 functional (meth) acrylates, and the bifunctional (meth) acrylate content is 70%.
The resin composition for an active energy ray-curable ink according to claim 7, which is not less than 10% by weight.