JP2000327709A - Energy ray curing type aqueous resin composition and overprint varnish - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of being optionally diluted and washed with a solvent such as water or an alcohol, excellent in workability and environmental preservability and good in adhesion to printing inks without using a primer by including a water-soluble resin having an ethylenically unsaturated group in the molecule, a tertiary amine compound and a specific polymer. SOLUTION: This composition is obtained by including (A) a water-soluble resin having one or more ethylenically unsaturated groups in the molecule [e.g. glycerol polyethoxytri(meth)acrylate], (B) a tertiary amine compound (e.g. triethanolamine or N,N-diethylaminoethyl methacrylate) and (C) a polymer soluble in an alcohol and water and having preferably 5,000-70,000 average molecular weight (e.g. polyvinyl alcohol or methyl cellulose). In the above composition, the amounts of the contained components are preferably 40-94 wt.% of the component A, 0.5-20 wt.% of the component B and 0.5-20 wt.% of the component C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an energy ray-curable aqueous resin composition, an overcoat agent for the energy ray-curable aqueous resin composition, and an overprint varnish. More specifically, it can be arbitrarily diluted and washed with a solvent such as water or alcohol, and is excellent in workability and environmental security. In addition, it has good adhesion to a printing ink without using a primer, and further has a good The present invention relates to an energy-ray-curable overprint varnish having less darkening due to spotting.

[0002]

BACKGROUND OF THE INVENTION Active energy ray-curable resin compositions are:
In recent years, from the viewpoint of excellent safety without solvent and its performance and productivity, for various plastic films,
It is used in various applications such as wood coating agents and printing inks. Among them, overprint varnish is applied and printed for the purpose of protecting printing surface of paper, plastic film, etc., improving blocking resistance, abrasion resistance, scratch resistance and obtaining a high gloss printing surface at the same time. Coating agent. Examples of gloss processing include paperware, labels, stickers,
It can be found on record jackets, book covers and sacks, magazines and catalog covers, postcards and posters. Typical methods for gloss processing include so-called vinyl drawing, press coating, print lamination, and the like. In recent years, a high gloss printing surface has been obtained while simultaneously improving blocking resistance, abrasion resistance, chemical resistance, and the like. Active energy ray-curable overprint varnishes are increasingly used.

[0003] However, these active energy ray-curable overprint varnishes have a disadvantage that their adhesion to various inks is poor due to distortion due to shrinkage during curing. In addition, when coated cardboard or the like is used as the base material, not only glossiness does not appear but also blackening occurs due to the penetration of the active energy ray-curable overprint varnish into the paper. In order to solve such adhesion and darkening, it is generally necessary to apply a primer coat in advance. Further, in the case where the overprint varnish is subjected to in-line gravure coating immediately after printing, it is necessary to dilute the solvent because the viscosity must be reduced. Although it is possible to use low-viscosity monomers as diluents instead of solvent dilution, such low-viscosity monomers generally cause odor because they are easily volatilized, and many of them have high skin irritation. It is necessary to use an organic solvent for cleaning the equipment.

[0004]

As means for solving these problems, an emulsion in which an active energy ray-curable resin is emulsified with a surfactant has been proposed. Furthermore, it is conceivable to incorporate a polymer emulsion emulsion-polymerized in order to improve adhesion. However,
In general, polymer emulsions obtained by emulsion polymerization have problems such as the use of an emulsifier and poor transparency and gloss of the resulting film due to poor compatibility with the active energy ray-curable resin. Further, in order to increase the drying speed, it is practically necessary to dilute with an alcoholic solvent such as IPA, but in this case, there is a disadvantage that the emulsion is broken and precipitates. A method of using a water-soluble active energy ray-curable resin is also conceivable, but those that satisfy blocking resistance, abrasion resistance, scratch resistance, and chemical resistance have poor stability when diluted with water. It was not practical because of easy separation, and adhesion to various inks was poor. Further, when coated cardboard is used as the base material, there is a drawback that there is a blackening phenomenon due to penetration. In any case, it can be diluted and washed arbitrarily with water or alcohol-based solvent, and is excellent in workability and environmental security, and has good adhesion to printing inks without using a primer. The purpose of obtaining an energy ray-curable overprint varnish with less darkening due to spotting has not yet been achieved.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, completed the present invention. That is, the present invention provides (1) a water-soluble resin (A) having at least one ethylenically unsaturated group in a molecule, a tertiary amine compound (B), and a polymer (C) soluble in alcohol and water. (2) The energy ray-curable aqueous resin composition according to (1), wherein the water-soluble resin (A) has an acyclic structure and a water miscibility of 7% or more. 3) The water-soluble resin (A) has a hydroxyl group,
The energy ray-curable aqueous resin composition according to (2), which is a (meth) acrylate having a carboxyl group or an ethylene oxide chain, (4) the water-soluble resin (A) is a glycerin derivative (meth) acrylate (1) (3) The energy ray-curable aqueous resin composition according to any one of (1) to (4), wherein the polymer (C) soluble in alcohol and water has an average molecular weight of 5,000 to 70,000. The energy ray-curable aqueous resin composition according to (1), wherein (6) contains 5 to 50% by weight of water (1).
To (5), and (7) an overcoat comprising the energy ray-curable aqueous resin composition according to any one of (1) to (6). Print varnish.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition of the present invention is dissolved in a water-soluble resin (A) having one or more ethylenically unsaturated groups in a molecule, a tertiary amine compound (B), an alcohol and water. An energy ray-curable aqueous resin composition containing a possible polymer (C).

The water-soluble resin (A) having one or more ethylenically unsaturated groups in the molecule used in the present invention includes:
Examples thereof include a vinyl monomer which is liquid at normal temperature, N-methoxymethylacrylamide, and (meth) acrylates. Among them, (meth) acrylates are preferable, and the structure thereof includes a hydrophilic group such as a hydroxyl group, a carboxyl group, a sulfone group, and an ethylene oxide chain. Those having a functional group are preferred. Also,
A water-soluble resin having an acyclic structure (having no cyclic group) and a water miscibility of 7% or more is more preferred. Among them, a glycerin derivative (meth) acrylate having a water miscibility of 7% or more is particularly preferable. Here, the water mixing ratio is defined as resin 10
It represents parts by weight of water that can be uniformly added to 0 parts by weight.

The amount of the water-soluble resin (A) having one or more ethylenically unsaturated groups in the molecule is usually from 40 to 94% by weight, preferably from 40 to 94% by weight, based on the total weight of the energy ray-curable aqueous resin composition. It is in the range of 50-80% by weight.

The (meth) acrylates, which are one type of the water-soluble resin (A) having one or more ethylenically unsaturated groups in the molecule, include, for example, hydroxyethyl (meth) acrylate, hydroxy (meth) acrylate, hydroxy Propyl (meth) acrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, 1,4-butanediol diepoxy (meth) acrylate, 1,6-hexanediol diepoxy (meth)
Acrylate, polyethylene glycol diepoxy (meth) acrylate, neopentyl glycol diepoxy (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropanepolyethoxytri (meth) acrylate, trimethylolpropanepolypropoxypolyethoxytri (meth) ) Acrylate, pentaerythritol polyethoxytri (meth) acrylate, pentaerythritol polyethoxytetra (meth) acrylate, ditrimethylolpropane polyethoxytetra (meth) acrylate, dipentaerythritol polyethoxytetra (meth) acrylate, dipentaerythritol polyethoxy Penta (meth) acrylate, dipentaerythritol polyethoxyhexa (meth) acrylate Commonly used monomers and oligomers such as, polyether (meth) acrylate, polyester (meth) acrylate, silicone (meth) acrylate, polybutadiene (meth) acrylate, polyamide (meth) acrylate, polyurethane (meth) acrylate, and acryloylmorpholine Among them, water-soluble ones can be mentioned. Among these, polyfunctional (meth) acrylate monomers and oligomers are preferred in view of performance such as odor and gloss.

[0010] Among them, glycerin polyethoxytri (meth) acrylate, glycerin polyethoxydi (meth)
Glycerin (C2-C3) alkylene oxide derivatives such as glycerin polyethoxy (meth) acrylate, glycerin diepoxy (meth) acrylate, glycerin epoxy (meth) acrylate, etc.
Acrylates are preferable, and among them, (meth) acrylate of a glycerin (C2-C3) alkylene oxide derivative having a hydroxyl group is more preferable. In addition, water mixing rate 7%
The above are particularly preferred for use in the present invention. Mixtures of (meth) acrylates of alkylene oxide derivatives of glycerin can be used.

The structure of the water-soluble resin (A) having one or more ethylenically unsaturated groups in the molecule is preferably a non-cyclic structure, but even a cyclic structure has a hydrophilic group such as a hydroxyl group, a carboxyl group, or an ethylene oxide chain. Those having a carboxyl group are preferred, and those having a carboxyl group which has been made water-soluble by neutralizing the group with an amine or alkali can be used.

The tertiary amine compound (B) used in the present invention includes triethanolamine, N-methyldiethanolamine, N, N-dimethylacrylamide, N, N
Non-aromatic tertiary amines such as -diethylacrylamide, N-isopropylacrylamide and N, N-diethylaminoethyl methacrylate are preferable, and tertiary amine compounds soluble in water or alcohol are preferable. The amount used is the stability of the energy ray-curable aqueous resin composition,
In consideration of performance such as adhesion, friction resistance, and blocking resistance of the obtained film, it is usually 0.5 to 20% by weight, more preferably 1 to 10% by weight, based on the total weight of the energy ray-curable resin composition. % Range.

As the polymer (C) soluble in alcohol and water used in the present invention, those generally used can be used, for example, polyvinyl alcohol, methylcellulose, methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, polyvinylpyrrolidone. , Polyacrylamide, polyacrylic acid, starch and derivatives thereof, casein, gelatin and other water-soluble polymers, acrylic acid / styrene copolymer, styrene-maleic anhydride copolymer, iso (or diiso) butylene-maleic anhydride Polymers made water-soluble by converting acid copolymers, copolymers of isobutylene / maleic anhydride / N-phenylmaleimide, acrylic-silicone copolymers, polyurethanes, polyesters, etc. into alkali salts or ammonium salts And the like. The average molecular weight of the polymer (C) that is soluble in alcohol and water is determined in consideration of the viscosity of the energy ray-curable aqueous resin composition, darkening due to penetration into the base, adhesion of the resulting film, and chemical resistance. It is preferably in the range of 5,000 to 70,000, and the amount used is usually in the range of 0.5 to 20% by weight, more preferably 2 to 10% by weight.

The energy ray-curable aqueous resin composition used in the present invention may or may not be cured with an electron beam. However, when it is cured with an ultraviolet ray, a photopolymerization initiator may be used. A polymerization accelerator is used. As the photopolymerization initiator, for example, acetophenone, benzophenone, benzoin ether, chloroacetophenone, diethoxyacetophenone, hydroxyacetophenone, α-aminoacetophenone, benzylmethyl ketal, thioxanthone, α-acyl oxime ester, acyl phosphine oxide, glyoxy ester, 3-ketocoumarin, 2
-Ethylanthraquinone, camphorquinone, benzyl and the like. As photopolymerization accelerators, amine compounds such as N-methyldiethanolamine, triethanolamine, diethanolamine, isoamyl ester of P-dimethylaminobenzoic acid, N, N-diethyl-P-aminobenzonitrile, and tri-n-butylphosphine Or a chlorine compound such as hexachloroethane, Michler's ketone, etc., alone or in combination of two or more. The mixing ratio of the polymerization initiator and the accelerator is preferably 0.1 to 15%, more preferably 0.5 to 10%, based on the total weight of the composition.
It is.

Water may be added to the energy ray-curable aqueous resin composition used in the present invention, if necessary, for the purpose of adjusting viscosity and the like. Also plasticizers, stabilizers, waxes, slip agents, dispersants, fillers, defoamers, UV absorbers,
Known additives such as an antioxidant, a polymerization inhibitor, an antistatic agent, and a fluorescent dye may be added.

The energy ray-curable aqueous resin composition thus obtained is stable over time, and is stable even when diluted with an alcoholic solvent or water as required during coating.

As a method of forming a cured film of the energy ray-curable aqueous resin composition, a bar coater coating,
Coating by air knife coating, gravure coating, offset printing, flexographic printing, screen printing, or the like by a method known per se so that the film thickness in a dry state is about 1 to 20 μm, drying, and then ultraviolet light or electron The coating film is cured by irradiating energy rays such as radiation. In this case, when curing with an electron beam, an electron beam accelerator having an energy of 100 to 500 eV is preferable. On the other hand, in the case of curing with ultraviolet rays, a xenon lamp, a high-pressure mercury lamp, and an ultraviolet irradiation device having a metal halide lamp are used as the light source, and the amount of light and the arrangement of the light source are determined as necessary. ~ 120W / cm
Transport speed of 20-60m /
It is preferable to cure by irradiating 1 to 4 times per minute.

[0018]

EXAMPLES The present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. still,
In the examples, parts mean parts by weight.

Example 1 TO-1343 (Note 1) 42 parts PEG-400DA (Note 2) 10 parts Photoinitiator (Irgacure 184; Ciba Geigy) 2 parts Diethylaminoethyl methacrylate 8 parts US-450 (Note 3) 26 Part Water 12 parts First, a photoinitiator is dissolved in a mixed solution of TO-1343 and PEG-400DA, and then diethylaminoethyl methacrylate and water are added and mixed, and then US-450 is mixed. A curable aqueous resin composition was obtained. This energy ray-curable aqueous resin composition is IP
A: Water: diluted to a suitable viscosity with a 1: 1 solution, coated onto cardboard and a substrate printed and dried with gravure ink on coated cardboard, and coated with a bar coater at a dry coating weight of 5 g / m.
² (film thickness 5 μm), dried and dried.
UV irradiator with high pressure mercury lamp of W / cm (GS
Conveyor speed 1 by ASE-20 (manufactured by Nippon Battery)
The energy ray-curable aqueous resin composition was cured by irradiation once at 0 m / min.

Example 2 DA-314-90M (Note 4) 54 parts ACMO (Note 5) 10 parts Photoinitiator (Irgacure 184; Ciba-Geigy) 2 parts N-methyldiethanolamine 5 parts US-450 13 parts Water 16 Part An energy ray-curable aqueous resin composition of the present invention was obtained in the same manner as in Example 1 except that the above composition was used instead of the composition of Example 1.

Example 3 DA-314-90M 44 parts SR-9035 (Note 6) 10 parts Dipentaerythritol polyethoxyhexaacrylate 10 parts Photoinitiator (Irgacure 184) 2 parts Diethylaminoethyl methacrylate 3 parts Joncryl 70 ( Note 7) 17 parts water 14 parts An energy ray-curable aqueous resin composition of the present invention was obtained in the same manner as in Example 1 except that the above composition was used instead of the composition of Example 1.

Example 4 DA-314-90M 33 parts GE-3A (Note 8) 10 parts SR-9035 10 parts ACMO 10 parts Photoinitiator (Irgacure 184) 2 parts N-methyldiethanolamine 3 parts Joncryl 70 17 Part water 15 parts An energy ray-curable aqueous resin composition of the present invention was obtained in the same manner as in Example 1 except that the above composition was used instead of the composition of Example 1.

Comparative Example 1 R-167 (Note 9) 25 parts R-551 (Note 10) 20 parts ACMO 20 parts Photoinitiator (Irgacure 184) 2 parts Water 10 parts Instead of the composition of Example 1, A comparative energy ray-curable resin composition was obtained in the same manner as in Example 1 except that the composition of Example 1 was used.

(Note 1) Aronix TO-1343 (polyester acrylate); manufactured by Toagosei Co., Ltd. (Note 2) KAYARAD PEG-400DA (polyethylene glycol diacrylate); manufactured by Nippon Kayaku Co., Ltd. (Note 3) Cymac US -450 (30% aqueous solution of acrylic silicone polymer); manufactured by Toagosei Co., Ltd. (Note 4) Denacol acrylate DA-314-90M
(Glycerin trypoxy acrylate); manufactured by Nagase Kasei Co., Ltd. (Note 5) ACMO (acryloylmorpholine);
* 6 SR-9035 (ethoxylated trimethylolpropane triacrylate); * 7 manufactured by Kayaku Sartomer Co., Ltd. * 7 Joncryl 70 (30% of acrylic polymer)
Aqueous solution); manufactured by Johnson Polymer (Note 8) New Frontier GE-3A (ethoxylated glycerin triacrylate); manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (Note 9) KAYARAD R-167 (1,6-hexanediol diepoxy acrylate) ; Nippon Kayaku Co., Ltd.
(Note 10) KAYARAD R-551 (EO-modified bisphenol A diacrylate); manufactured by Nippon Kayaku Co., Ltd.

The properties of the thus obtained energy ray-curable aqueous resin composition and the obtained cured product were evaluated,
Table 1 shows the results. The following evaluation criteria were used.

Table 1 Evaluation Results Stability Curability Ink portion gloss Uncoated portion gloss Infiltration Adhesion Example 1 ○ ○ 8375 ○ ○ ○ 2 ○ ○ 81 76 ○ ○ ○ 3 ○ ○ 78 78 ○ ○ ○ 4 ○ ○ 80 79 ○ ○ Comparative Example 1 × ○ 80 63 × ×

(1) Stability The obtained resin composition was allowed to stand at room temperature for 5 days, and the state was visually observed and evaluated. ；: The liquid state was uniform without any change. X: Separation was observed. (2) Curability The obtained cured product was evaluated by finger touch. ；: There was no tack. X: There was tack.

(3) Gloss A 60-degree specular gloss was measured for each of the ink portion and the uncoated portion. (4) Penetration In the uncoated part, unevenness in gloss and darkening due to the penetration of the resin composition were visually observed. ；: There was no unevenness in gloss and darkening due to penetration. X: There was uneven gloss and darkening due to spotting. (5) Adhesion In the ink part, 90-degree peeling was tested with a Nichiban tape of 24 mm. ；: No peeling was observed between the ink and the cured film. X: Peeling occurred between the ink and the cured film.

As is clear from Table 1, the energy ray-curable aqueous resin composition of the present invention has good stability. Further, without using a primer, the adhesiveness to printing ink is good, and a blackening phenomenon due to penetration into a base is small, and a high gloss film can be obtained.

[0030]

The water-soluble resin (A) having one or more ethylenically unsaturated groups in the molecule and the tertiary amine compound (B)
And the energy ray-curable aqueous resin composition of the present invention containing an alcohol and a polymer (C) soluble in water, can be arbitrarily diluted and washed with water or an alcohol-based solvent, and have excellent workability and environmental safety. And good adhesion to printing ink and the like without using a primer. Further, a blackening phenomenon due to the penetration of the underlayer is small, and a high-gloss film is obtained, which is particularly useful as an overprint varnish for paper.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09D 5/00 C09D 5/00 CF Term (Reference) 4J011 PA36 PA53 PA55 PA67 PA69 PA70 PA74 PB40 PC02 PC08 QA02 QA03 QA06 QA07 QA08 RA02 RA03 RA04 RA07 RA09 SA05 SA06 SA07 SA12 SA22 SA32 SA43 SA44 SA63 SA64 SA65 SA82 SA84 UA01 UA03 VA01 WA01 WA02 4J027 AA02 AA04 AB01 AB10 AC01 AC06 AD02 AF01 AF05 AG01 CA25 CB10 BA03 4 CG082 CG141 CG172 CH121 CH131 CH141 CH161 CH171 CH191 CH221 CK032 DD032 DG002 DL032 DL121 GA02 GA03 GA06 HA156 JB09 JB13 MA08 MA14 PA17

Claims (7)

[Claims] 1. A water-soluble resin (A) having at least one ethylenically unsaturated group in a molecule and a tertiary amine compound (B)
And an energy ray-curable aqueous resin composition containing a polymer (C) soluble in alcohol and water. 2. The energy ray-curable aqueous resin composition according to claim 1, wherein the water-soluble resin (A) has an acyclic structure and has a water miscibility of 7% or more. 3. The energy ray-curable aqueous resin composition according to claim 2, wherein the water-soluble resin (A) is a (meth) acrylate having a hydroxyl group, a carboxyl group or an ethylene oxide chain. 4. The energy ray-curable aqueous resin composition according to claim 1, wherein the water-soluble resin (A) is a (meth) acrylate of a glycerin derivative. 5. The energy-ray-curable aqueous resin composition according to claim 1, wherein the polymer (C) soluble in alcohol and water has an average molecular weight of 5,000 to 70,000. 6. The energy ray-curable aqueous resin composition according to claim 1, comprising 5 to 50% by weight of water. 7. An overprint varnish comprising the energy ray-curable aqueous resin composition according to any one of claims 1 to 6.