JP2016199727A - Polyester resin, lithographic printing ink and printed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable lithographic printing ink that is subjected to an environmental protection measure and achieves both printing suitability and print film strength, and a printed matter of the ink.SOLUTION: The active energy ray-curable lithographic printing ink comprises a polyester resin (A), a pigment, an acrylate oligomer, an acrylate monomer, and a photo-initiator. The polyester resin (A) is prepared by reacting 5 to 25 wt.% of rosin (a), 15 to 50 wt.% of a compound (b) having two or more carboxyl groups, 10 to 45 wt.% of isosorbide (c), and 15 to 45 wt.% of polyol (d) (excluding isosorbide (c)).SELECTED DRAWING: None

Description

  The present invention relates to a novel polyester resin. The polyester resin can be used in, for example, a lithographic printing ink, particularly an active energy ray-curable lithographic printing ink that can be cured by irradiation with active energy rays such as ultraviolet rays and electron beams.

  The lithographic printing ink is an ink having a relatively high viscosity of 5 to 100 Pa · s. The mechanism of the lithographic printing machine is such that ink is supplied from the ink fountain of the printing machine to the image line area of the printing plate via multiple rollers, and in lithographic printing using dampening water, dampening water is supplied to the non-image area area. In lithographic printing without dampening water, the non-image area is made of a silicon layer, and the ink is repelled to form an image on the paper.

  In particular, in lithographic printing using a fountain solution, the emulsification balance between the ink and the fountain solution is important, and the ink is also required to have high emulsification resistance and high-speed printability. If the amount of emulsified ink is too high, the ink will easily deposit on non-image areas and stains will occur. If the amount of emulsified is small, dampening water will be sprinkled on the ink surface when printing with a small pattern, so that Ink transfer and ink inking onto paper deteriorate, making it difficult to print stably.

  Furthermore, in recent years, demands for labor saving, labor saving, automation, and high speed during printing have increased, and in particular, the printing speed has been increasingly increased. In addition, there is a demand for a printing ink that can obtain a high-quality printed matter stably for a long time without any trouble under various printing conditions, and ink manufacturers have made various improvements.

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

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

  As active energy ray-curable binder resins, unsaturated polyester resins, polyester acrylate resins, epoxy acrylate resins, urethane acrylate resins and the like have been studied. For example, Patent Document 1 discloses a resin obtained by modifying a saturated polyester with an isocyanate group-containing urethane acrylate.

  In the conventional report, in order to produce a polyester resin used as an active energy ray-curable binder resin, rosins and 1,4: 3,6-dianhydro-D-sorbitol of a diol having the structure shown below ( Hereinafter, there was no description using isosorbide (isosorbide).

  Isosorbide is commonly known as a monomer for incorporation into polyester resins for food and beverage container applications. Isosorbide is a diol that can serve as a partial replacement for other diols, including ethylene glycol and 1,4-cyclohexanedimethanol. Isosorbide can be incorporated as a monomer in a polyester containing a terephthaloyl moiety. Isosorbide improves the thermal properties of certain polyesters by raising the glass transition temperature of the polymer. This monomer can also improve the performance of the polymer in a variety of applications where conventional polyesters cannot perform the same function. These properties add value to markets such as polyethylene terephthalate (PET) rigid containers and thermoplastics.

  Isosorbide is a plant-derived diol obtained by dehydrating cyclization of sorbitol, which is a natural sugar, and is a compound with a small environmental burden even when incinerated. For this reason, as a monomer source for obtaining a polycarbonate having a small influence on global warming, its utilization has recently been studied (for example, Patent Document 2).

  Conventionally, binder resins used for active energy ray curable lithographic offset printing inks, active energy ray curable compounds such as acrylic ester compounds, pigments, radical polymerization initiators, and various additives are petroleum-derived raw materials. Consideration has been made to switch to low environmental impact by decalcification. By using isosorbide as a monomer incorporated into polyester resin, development of low environmental impact ink is expected.

  Conventional reports describe that rosin-modified phenolic resins are widely used in lithographic ink resins except for active energy ray-curable inks. In general, this rosin-modified phenolic resin is obtained by reacting a resol-type phenolic resin obtained by reacting phenols and formaldehyde under a basic catalyst with rosins and various polyhydric alcohols. The bulky structure obtained by the reaction of rosins and resol type phenolic resin can realize ink viscoelasticity suitable for printability required for lithographic ink. However, there are few examples in which rosins are used as a raw material for the binder resin used in the active energy ray-curable ink.

  As the rosins, gum rosin obtained by refining from rosin is frequently used, but since it is a natural raw material, it is a compound with a small environmental load.

  The present invention is expected to realize ink viscoelasticity suitable for printability by using isosorbide and a polyol other than isosorbide as a raw material for the binder resin.

JP 2001-348516 A International Publication No. 08/029746 Pamphlet

An object of the present invention is to provide a polyester resin suitable for an active energy ray-curable lithographic printing ink that is environmentally friendly and has both printability and print film strength, and a printing ink and printed matter thereof.

  As a result of intensive studies, the present inventors have found that rosins (a), compounds having two or more carboxyl groups (b), isosorbide (c), and polyol (d) (except for isosorbide (c)) The polyester resin obtained by reacting the above is suitable as an ink binder, and by using the polyester resin in the binder resin, an active energy ray-curable lithographic printing ink capable of achieving both excellent printability and printing film strength can be obtained. As a result, the present invention has been completed.

  That is, the present invention is obtained by reacting rosins (a), a compound (b) having two or more carboxyl groups, isosorbide (c), and polyol (d) (excluding isosorbide (c)). It relates to the polyester resin (A).

Moreover, this invention is based on the whole polyester resin (A).
Rosin (a) 5-25 wt%,
15 to 50% by weight of compound (b) having two or more carboxyl groups;
10 to 45% by weight of isosorbide (c),
The present invention relates to the polyester resin (A) obtained by reacting 15 to 45% by weight of the polyol (d).

  The present invention also relates to an ink binder comprising the polyester resin (A).

  The present invention also relates to an active energy ray-curable lithographic printing ink comprising the ink binder, a pigment, an acrylate oligomer and / or an acrylate monomer.

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

  The present invention relates to a polyester resin (A) obtained by reacting rosins (a), a compound (b) having two or more carboxyl groups, isosorbide (c), and polyol (d) (excluding isosorbide (c)). ) -Containing printing inks, and a method for synthesizing a composition for printing inks that is environmentally friendly and that can obtain a high-quality printed matter with gloss even when printed under conventional conditions, and An ink using it could be provided.

  First, the rosins (a) in the present invention will be described.

  The rosins (a) used for obtaining the polyester resin (A) of the present invention include natural rosins such as gum rosin, tall oil rosin and wood rosin, polymerized rosin derived from the natural rosin, natural rosin and polymerized rosin. Examples thereof include a stabilized rosin obtained by leveling or hydrogenation, an unsaturated acid-modified rosin obtained by adding an unsaturated carboxylic acid to a natural rosin or a polymerized rosin. The unsaturated acid-modified rosin is, for example, maleic acid-modified rosin, maleic anhydride-modified rosin, fumaric acid-modified rosin, itaconic acid-modified rosin, crotonic acid-modified rosin, cinnamic acid-modified rosin, acrylic acid-modified rosin, methacrylic acid Examples thereof include modified rosin and acid-modified polymerized rosin corresponding thereto. These may be used alone or in combination of two or more.

  The compound (b) having two or more carboxyl groups in the present invention will be described.

The compound (b) having two or more useful carboxyl groups used for obtaining the polyester resin (A) of the present invention is preferably an aromatic dicarboxylic acid having 6 to 40 carbon atoms, more preferably 8 to 14 carbon atoms. An aliphatic dicarboxylic acid having 2 to 40 carbon atoms, more preferably 4 to 12 carbon atoms; or an alicyclic dicarboxylic acid having 5 to 40 carbon atoms, more preferably 8 to 12 carbon atoms. It is not limited to.
Examples of dicarboxylic acids useful in the present invention include, but are not limited to: Terephthalic acid, isophthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, cyclohexanediacetic acid, 5-sodiosulfoisophthalic acid, Adipic acid, azelaic acid, glutaric acid, maleic acid, malonic acid, dimethylmalonic acid, allylmalonic acid, oxalic acid, sebacic acid, succinic acid, sulfoisophthalic acid, 2,5-furandicarboxylic acid, 2,5-thiophenedicarboxylic acid 3,4′- and 4,4′-diphenyl sulfide dicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, naphthalene dicarboxylate, 3,4′- and 4,4′-diphenylsulfone dicarboxylic acid, 3, 4'- and 4,4'-benzophenone dicarboxylic acid, 4,4'-methylenebis Rohexyl) dicarboxylic acid, trans-1,4-cyclohexanedicarboxylic acid, cis-1,4-cyclohexanedicarboxylic acid, cis- and / or trans-1,3-cyclohexanedicarboxylic acid, 4-cyclohexane-1,2-dicarboxylic acid 2-ethylsuberic acid, 1,2-bis (4-carboxyphenoxy) ethane, 4,4′-methylene-bis (benzoic acid), 4,4′-methylene-bis (cyclohexyl) carboxylic acid, 3,4 -Furandicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, p-carboxyphenyl / oxybenzoic acid, ethylene (p-oxybenzoic acid), trans-4,4'-stilbene dicarboxylic acid, 2,2,3,3- Tetramethylsuccinic acid, cyclopentanedicarboxylic acid, decahydro-1,5-naphthylenedicarboxylic acid, decahydro Cahydro-2,6-naphthylene dicarboxylic acid, 4,4′-bicyclohexyldicarboxylic acid, fumaric acid, dimer acid, resorcinol diacetic acid, and 4,4′-dibenzoic acid, which are used alone or in combination To use.

  When cyclohexanedicarboxylic acid is used in the present invention, cis-, trans-, or cis / trans mixtures can be used. Any naphthalene dicarboxylic acid isomer or isomer mixture can be used. Some of the preferred naphthalenedicarboxylic acid isomers include 2,6-, 2,7-, 1,4- and 1,5-isomers.

  Small amounts of trifunctional acids such as 1,3,5-benzenetricarboxylic acid can also be used. Furthermore, “aromatic” and “alicyclic” are meant to include substituted aromatic or alicyclic compounds, such as aromatic compounds substituted with an aliphatic group. These acids can be used alone or in combination.

  The isosorbide (c) of the present invention is the compound shown in the above chemical formula 1, and has an advantageous effect in that it is a compound with a small environmental load.

  Furthermore, it has an advantageous effect in that the thermal properties of the polyester are improved, and high film strength is imparted to the printing ink using this polyester resin as a binder resin.

  In the present invention, polyol (d) is used to increase the molecular weight of the polyester resin. The hydroxyl group of the polyol (d) and the carboxylic acid (b) undergo an esterification reaction to increase the molecular weight.

  Polyol (d) is a linear alkylene dihydric alcohol, 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1, 4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,7 -Heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1,12-dodecanediol, 1,2- Dodecanediol, 1,14-tetradecanediol, 1,2-tetradecanediol, 1,16-hexadecanediol, 1,2- Kisa decanediol, etc.,

2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-2-propyl-1,3-propanediol, 2,4-dimethyl, which are branched alkylene dihydric alcohols -2,4-dimethylpentanediol, 2,2-diethyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, dimethyloloctane, 2-ethyl-1,3 -Hexanediol, 2,5-dimethyl-2,5-hexanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, 2,4-diethyl-1 , 5-pentanediol, etc.

1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cycloheptanediol, tricyclodecane dimethanol, hydrogenated catechol, hydrogenated resorcinol which are cyclic alkylene dihydric alcohols , Hydrogenated hydroquinone, etc.

Further examples include polyether polyols such as polyethylene glycol (n = 2 to 20), polypropylene glycol (n = 2 to 20), and polytetramethylene glycol (n = 2 to 20), polyester polyols, and the like.

  Furthermore, as trihydric or higher alcohol, glycerin, trimethylolpropane, pentaerythritol, 1,2,6-hexanetriol, 3-methylpentane-1,3,5-triol, hydroxymethylhexanediol, trimethyloloctane, Examples include diglycerin, ditrimethylolpropane, dipentaerythritol, sorbitol, inositol, tripentaerythritol and the like.

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

The polyester resin (A) of the present invention comprises 5 to 25% by weight of rosins (a),
15 to 50% by weight of compound (b) having two or more carboxyl groups;
10 to 45% by weight of isosorbide (c),
It is preferable to esterify 15 to 45% by weight of the polyol (d) and 100% by weight.

  The polyester resin (A) obtained by the above reaction preferably has a weight average molecular weight of 10,000 to 30,000 in terms of polystyrene measured by gel permeation chromatography (GPC), an acid value of 60 or less, and a melting point of 60 ° C. or more. Except for the above range, emulsification suitability and transferability when printing ink is used are not preferable.

The polyester resin (A) of the present invention is suitably used as an ink binder for lithographic printing ink, intaglio printing ink, relief printing ink, stencil printing ink, writing ink, inkjet ink and the like.
Especially, it is useful as a binder for lithographic printing inks, especially as an active energy ray-curable lithographic printing ink binder.

  The active energy ray-curable lithographic printing ink of the present invention contains 10 to 40% by weight of the polyester resin (A), 30 to 75% by weight of acrylate oligomer and / or acrylate monomer, and 5 to 40% by weight of pigment. It is.

  The acrylate monomer in the present invention is a compound having an acrylic group and / or a methacryl group in the molecule.

  Specifically, monofunctional acrylate monomers such as 2-ethylhexyl acrylate, methoxydiethylene glycol acrylate, acryloylmorpholine,

  Ethylene glycol diacrylate, polyethylene glycol diacrylate (n = 2 to 20), propylene glycol diacrylate, polypropylene glycol diacrylate (n = 2 to 20), alkane (4 to 12 carbon atoms) glycol diacrylate, alkane (carbon number) 4-12) glycol ethylene oxide adduct (2-20 mol) diacrylate, alkane (4-12 carbon atoms) glycol propylene oxide adduct (2-20 mol) diacrylate, hydroxypivalyl hydroxypivalate diacrylate, tri Cyclodecane dimethylol diacrylate, bisphenol A ethylene oxide adduct (2 to 20 mol) diacrylate, hydrogenated bisphenol A diacrylate, hydrogenated bisphenol A ethylene oxide addition (2-20 moles) bifunctional acrylate monomers such as diacrylates,

Glycerin triacrylate, glycerin ethylene oxide adduct (3-30 mol) triacrylate, glycerin propylene oxide adduct (3-30 mol) triacrylate, trimethylolpropane triacrylate, trimethylolpropane ethylene oxide adduct (3-30 mol) ) Triacrylate, trimethylolpropane propylene oxide adduct (3-30 mol) trifunctional acrylate monomers such as triacrylate, pentaerythritol tetraacrylate, pentaerythritol ethylene oxide adduct (4-40 mol) tetraacrylate, pentaerythritol propylene oxide Additives (4-40 mol) tetraacrylate, diglycerin tetraacrylate, pentaerythritol ethylene oxa Adduct (4-40 mol) tetraacrylate, pentaerythritol propylene oxide adduct (4-40 mol) tetraacrylate, ditrimethylolpropane tetraacrylate, ditrimethylolpropane ethylene oxide adduct (4-40 mol) tetraacrylate, ditri Tetrafunctional vinyl compounds such as methylolpropane propylene oxide adduct (4 to 40 mol) tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol ethylene oxide adduct (6 to 60 mol) hexaacrylate, dipentaerythritol propylene oxide adduct (6 to 60 mol) polyfunctional acrylate monomer such as hexaacrylate,
And mixtures thereof.

  The acrylate monomer can be appropriately selected according to the required properties of the cured film, and an oligomer such as polyester acrylate, polyurethane acrylate, or epoxy acrylate can be used in combination as necessary.

Next, examples of the pigment include inorganic pigments and organic pigments.
Examples of inorganic pigments include chrome-lead, zinc-yellow, bitumen, barium sulfate, cadmium red, titanium oxide, zinc white, dial, alumina white, calcium carbonate, ultramarine, carbon black, graphite, aluminum powder, etc.
Organic pigments include β-naphthol, β-oxynaphthoic acid, β-oxynaphthoic acid allylide, acetoacetyl allylide, pyrazolone, and other soluble azo pigments, β-naphthol, β-oxynaphthoic acid Insoluble azo pigments such as allylide, acetoacetate allylide monoazo, acetoacetate allylide disazo, pyrazolone, etc., copper phthalocyanine blue, halogenated (chlorine or brominated) copper phthalocyanine blue, sulfonated copper phthalocyanine blue, metal free phthalocyanine, etc. Phthalocyanine pigment, quinacridone, dioxazine, selenium (pyrantron, anthanthrone, indanthrone, anthrapyrimidine, flavantron, thioindigo, anthraquinone, perinone, perylene), isoindolinone, metal complex Various known and publicly available pigments such as quinophthalone-based polycyclic pigments and heterocyclic pigments can be used.

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

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

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

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

  The compounding quantity of a photoinitiator is 0.01-15 weight% in this printing ink, Preferably it is 0.05-10 weight%. If it is less than 0.01% by weight, the curing reaction is not sufficiently carried out, and if it exceeds 20 parts by weight, the thermal polymerization reaction is liable to occur and the stability as an ink is liable to be impaired.

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

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

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

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

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

As an example of the composition of the active energy ray curable lithographic printing ink used in the present invention,
Polyester resin (A) 10-40% by weight
Acrylate monomer 30-75% by weight
Pigment (organic pigment / inorganic pigment) 5-40% by weight
Photoinitiator 0.01-15% by weight
1-15% by weight of other ingredients
Is mentioned.

  In addition, a polymerization inhibitor is mentioned as another component.

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

  EXAMPLES Next, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited by these Examples. In the present invention, “part” represents part by weight, and “%” represents% by weight.

  In the present invention, the weight average molecular weight was measured by gel permeation chromatography (HLC-8220) manufactured by Tosoh Corporation. A calibration curve was prepared with a standard polystyrene sample. Tetrahydrofuran was used as the eluent, and three TSKgel SuperHM-M (manufactured by Tosoh Corporation) were used as the column. The measurement was performed at a flow rate of 0.6 ml / min, an injection volume of 10 μl, and a column temperature of 40 ° C. Furthermore, in the present invention, “molecular weight” means a weight average molecular weight unless otherwise specified.

  In the present invention, the acid value was measured by a neutralization titration method. As a measuring method, 1 g of a polyester resin was dissolved in 20 ml of a solvent mixed in a weight ratio of xylene: ethanol = 2: 1. Thereafter, 3 ml of a 3% by weight phenolphthalein solution was added as an indicator and neutralized with a 0.1 mol / l aqueous potassium hydroxide solution. The unit is mgKOH / g.

An active energy ray-curable lithographic ink composition was prepared according to the following formulation.
[Example 1]
A stirrer, a reflux condenser with a water separator, and a four-neck flask with a thermometer were charged with 25 parts of gum rosin, 15 parts of terephthalic acid, 45 parts of isosorbide, 15 parts of neopentyl glycol, 60 parts of xylene, and blowing nitrogen gas, Heated to 230 ° C.
Thereafter, 0.1 part of p-toluenesulfonic acid monohydrate was added, and dehydration condensation was carried out at 230 ° C. for 15 hours. Resin (R1) having an acid value of 31 and a weight-average molecular weight (Mw) of polystyrene equivalent in terms of GPC measurement of polystyrene )
Next, 34 parts of resin (R1), 65.9 parts of dipentaerythritol hexaacrylate, and 0.1 part of hydroquinone were mixed in the same flask, and heated and melted at 110 ° C. to obtain varnish (V1).
Furthermore, 20 parts of Lionol Blue FG7330 (a cyan pigment manufactured by Toyocolor Co., Ltd.), 63 parts of varnish (V1), 11.9 parts of trimethylolpropane tetraacrylate, 2.5 parts of 4,4′-bis (diethylamino) benzophenone, 2.5 parts of 2-methyl-2-monophorino (4-thiomethylphenyl) propan-1-one and 0.1 part of hydroquinone are kneaded with a three-roll mill at 40 ° C., and the tackiness of the ink is 9-10. Was adjusted with trimethylolpropane tetraacrylate to obtain a lithographic printing ink (C1).
The tack of the ink was measured with a roll temperature of 30 ° C., 400 rpm, and 1 minute after using an incometer manufactured by Toyo Seiki Co., Ltd.

[Example 2]
By the same operation as in Example 1, a resin (R2) having an acid value of 29 and Mw of 27,000 with the composition shown in Table 1 was obtained. Subsequently, lithographic printing ink (C2) was obtained with the composition shown in Table 2 and varnish (V2) with the composition shown in Table 3.

Example 3
In the same manner as in Example 1, a resin (R3) having an acid value of 26 and Mw of 21,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C3) was obtained with the composition shown in Table 2 and the varnish (V3) with the composition shown in Table 3.

Example 4
In the same manner as in Example 1, a resin (R4) having an acid value of 36 and Mw of 20,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C4) was obtained with the formulation shown in Table 2 and the varnish (V4) with the formulation shown in Table 3.

Example 5
By the same operation as in Example 1, a resin (R5) having an acid value of 17 and Mw of 24,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C5) was obtained with the composition shown in Table 2 and the varnish (V5) with the composition shown in Table 3.

Example 6
By the same operation as in Example 1, a resin (R6) having an acid value of 20 and Mw of 23,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C6) was obtained with the formulation shown in Table 2 and the varnish (V6) with the formulation shown in Table 3.

Example 7
By the same operation as in Example 1, a resin (R7) having an acid value of 31 and Mw of 30,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C7) was obtained with the composition shown in Table 2 and the varnish (V7) with the composition shown in Table 3.

Example 8
In the same manner as in Example 1, a resin (R8) having an acid value of 12 and Mw of 15,000 was obtained with the composition shown in Table 1. Subsequently, a lithographic printing ink (C8) was obtained with the composition shown in Table 2 and the varnish (V8) with the composition shown in Table 3.

[Comparative Example 1]
A stirrer, a reflux condenser with a water separator, and a thermometer four-necked flask were charged with 15 parts of gum rosin, 35 parts of terephthalic acid, 30 parts of neopentyl glycol, 20 parts of pentaerythritol, and 60 parts of xylene while blowing nitrogen gas. , Heated to 230 ° C.
Thereafter, 0.1 part of p-toluenesulfonic acid monohydrate was added, and dehydration condensation was carried out at 230 ° C. for 15 hours. A resin (RA) having an acid value of 32 and a weight average molecular weight (Mw) of 27,000 in terms of polystyrene measured by GPC. )
Next, 31.5 parts of resin (RA), 68.4 parts of dipentaerythritol hexaacrylate, and 0.1 part of hydroquinone were mixed in the same flask, and heated and melted at 110 ° C. to obtain a varnish (VA).
Furthermore, 20 parts of Lionol Blue FG7330 (Toyocolor Co., Ltd. indigo pigment), 62 parts of varnish (VA), 12.9 parts of trimethylolpropane tetraacrylate, 2.5 parts of 4,4′-bis (diethylamino) benzophenone, 2.5 parts of 2-methyl-2-monophorino (4-thiomethylphenyl) propan-1-one and 0.1 part of hydroquinone are kneaded with a three-roll mill at 40 ° C., and the tackiness of the ink is 9-10. Was adjusted with trimethylolpropane tetraacrylate to obtain a lithographic printing ink (CA).
The tack of the ink was measured with a roll temperature of 30 ° C., 400 rpm, and 1 minute after using an incometer manufactured by Toyo Seiki Co., Ltd.

[Comparative Example 2]
By the same operation as in Comparative Example 1, a resin (RB) having an acid value of 29 and Mw of 26,000 was obtained with the composition shown in Table 1. Subsequently, the lithographic printing ink (CB) was obtained with the composition shown in Table 2 and the varnish (VB) with the composition shown in Table 3.

[Comparative Example 3]
By the same operation as Comparative Example 1, a resin (RC) having an acid value of 21 and Mw of 30,000 was obtained with the composition shown in Table 1. Subsequently, varnish (VC) with the composition shown in Table 2 and lithographic printing ink (CC) with the composition shown in Table 3 were obtained.

[Comparative Example 4]
By the same operation as in Comparative Example 1, a resin (RD) having an acid value of 18 and Mw of 26,000 was obtained with the composition shown in Table 1. Subsequently, lithographic printing ink (CD) was obtained with the composition shown in Table 2 and varnish (VD) with the composition shown in Table 3.

[Comparative Example 5]
By the same operation as in Comparative Example 1, a resin (RE) having an acid value of 33 and Mw of 28,000 with the formulation shown in Table 1 was obtained. Subsequently, lithographic printing ink (CE) was obtained with the formulation shown in Table 2 and varnish (VE) with the formulation shown in Table 3.

[Comparative Example 6]
By the same operation as in Comparative Example 1, a resin (RF) having an acid value of 13 and Mw of 18,000 was obtained with the composition shown in Table 1. Subsequently, varnish (VF) was obtained with the formulation shown in Table 2, and lithographic printing ink (CF) was obtained with the formulation shown in Table 3.

  The lithographic printing inks obtained in the examples and comparative examples were evaluated for cured film properties and printability by the following methods.

<Evaluation of cured film properties>
The lithographic printing ink obtained in Examples 1 to 8 and Comparative Examples 1 to 6 was applied to maricoat paper (coated cardboard manufactured by Hokuetsu Paper Co., Ltd.) at 1 g / m using an RI tester (manufactured by Meiko Seisakusho). Printing was performed at a coating amount of ² , and ultraviolet rays were irradiated at 60 m / min using one 120 W / cm air-cooled metal halide lamp (manufactured by Toshiba).

  The curability, MEK resistance, friction resistance, and gloss value of the printed material after ultraviolet irradiation were evaluated. The evaluation results are shown in Table 4.

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

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

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

Gloss value is 60% gloss with gloss meter gloss meter model GM-26 (manufactured by Murakami Color Research Laboratory Co., Ltd.) with proof bow color developing machine and the same density on pearl coat manufactured by Mitsubishi Paper Industries. Was measured. The higher the value, the better the gloss.
(Evaluation criteria) ◎: 60 or more, ○: 50 or more to less than 60, Δ: 45 or more to less than 50, x: less than 45

  As shown in Table 4, there was no effect on curability with or without isosorbide.

Regarding MEK resistance, friction resistance, and gloss, the resin containing isosorbide gave better results than the resin containing no isosorbide.
Further, Examples 2, 5, 6, and 7 in which the molecular weight of the resin was large were good in terms of MEK resistance and friction resistance. This is probably because the film strength increases as the molecular weight increases.

Regarding the gloss, the resin containing isosorbide was better than the resin not containing isosorbide.
Furthermore, the lithographic printing inks of Examples 1 and 6 containing 40% by weight or more of isosorbide resulted in particularly excellent gloss values. The inclusion of isosorbide is considered to improve the fluidity of the ink and improve the leveling of the paper surface.

  Furthermore, it was confirmed that the maximum emulsification rate of the active energy ray-curable offset ink using the same organic pigment / inorganic pigment was increased by using rosins. When the maximum emulsification rate is high, the ability to take up the fountain solution is high even under conditions of excessive supply of the fountain solution, making it possible to maintain the optimum emulsification state and poor transfer to the plate or blanket surface. Troubles such as accumulated ink (piling) can be suppressed.

  Since the polyester resin (A) of the present invention is derived from natural products and mainly contains rosin and isosorbide, it is a low environmental load material such as packaging materials, containers, chemical products such as paints / adhesives, toners, and electronic materials. It can also be used as a main material or a secondary material.

Claims (5)

A polyester resin (A) obtained by reacting rosins (a), a compound (b) having two or more carboxyl groups, isosorbide (c), and polyol (d) (excluding isosorbide (c)). For the entire polyester resin (A),
Rosin (a) 5-25 wt%,
15 to 50% by weight of compound (b) having two or more carboxyl groups;
10 to 45% by weight of isosorbide (c),
The polyester resin (A) according to claim 1, wherein the polyester (A) is reacted with 15 to 45% by weight of the polyol (d). An ink binder comprising the polyester resin (A) according to claim 1. An active energy ray-curable lithographic printing ink comprising the ink binder according to claim 3, a pigment, and an acrylate oligomer and / or acrylate monomer. A printed matter obtained by printing the active energy ray-curable lithographic printing ink according to claim 4 on a substrate and curing the active energy ray with active energy rays.